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• 6 Facts About GlassFish Announcement

  - by Bruno.Borges

  Since Oracle announced the end of commercial support for future Oracle GlassFish Server versions, the Java EE world has started wondering what will happen to GlassFish Server Open Source Edition. Unfortunately, there's a lot of misleading information going around. So let me clarify some things with facts, not FUD. Fact #1 - GlassFish Open Source Edition is not dead GlassFish Server Open Source Edition will remain the reference implementation of Java EE. The current trunk is where an implementation for Java EE 8 will flourish, and this will become the future GlassFish 5.0. Calling "GlassFish is dead" does no good to the Java EE ecosystem. The GlassFish Community will remain strong towards the future of Java EE. Without revenue-focused mind, this might actually help the GlassFish community to shape the next version, and set free from any ties with commercial decisions. Fact #2 - OGS support is not over As I said before, GlassFish Server Open Source Edition will continue. Main change is that there will be no more future commercial releases of Oracle GlassFish Server. New and existing OGS 2.1.x and 3.1.x commercial customers will continue to be supported according to the Oracle Lifetime Support Policy. In parallel, I believe there's no other company in the Java EE business that offers commercial support to more than one build of a Java EE application server. This new direction can actually help customers and partners, simplifying decision through commercial negotiations. Fact #3 - WebLogic is not always more expensive than OGS Oracle GlassFish Server ("OGS") is a build of GlassFish Server Open Source Edition bundled with a set of commercial features called GlassFish Server Control and license bundles such as Java SE Support. OGS has at the moment of this writing the pricelist of U$ 5,000 / processor. One information that some bloggers are mentioning is that WebLogic is more expensive than this. Fact 3.1: it is not necessarily the case. The initial edition of WebLogic is called "Standard Edition" and falls into a policy where some “Standard Edition” products are licensed on a per socket basis. As of current pricelist, US$ 10,000 / socket. If you do the math, you will realize that WebLogic SE can actually be significantly more cost effective than OGS, and a customer can save money if running on a CPU with 4 cores or more for example. Quote from the price list: “When licensing Oracle programs with Standard Edition One or Standard Edition in the product name (with the exception of Java SE Support, Java SE Advanced, and Java SE Suite), a processor is counted equivalent to an occupied socket; however, in the case of multi-chip modules, each chip in the multi-chip module is counted as one occupied socket.” For more details speak to your Oracle sales representative - this is clearly at list price and every customer typically has a relationship with Oracle (like they do with other vendors) and different contractual details may apply. And although OGS has always been production-ready for Java EE applications, it is no secret that WebLogic has always been more enterprise, mission critical application server than OGS since BEA. Different editions of WLS provide features and upgrade irons like the WebLogic Diagnostic Framework, Work Managers, Side by Side Deployment, ADF and TopLink bundled license, Web Tier (Oracle HTTP Server) bundled licensed, Fusion Middleware stack support, Oracle DB integration features, Oracle RAC features (such as GridLink), Coherence Management capabilities, Advanced HA (Whole Service Migration and Server Migration), Java Mission Control, Flight Recorder, Oracle JDK support, etc. Fact #4 - There’s no major vendor supporting community builds of Java EE app servers There are no major vendors providing support for community builds of any Open Source application server. For example, IBM used to provide community support for builds of Apache Geronimo, not anymore. Red Hat does not commercially support builds of WildFly and if I remember correctly, never supported community builds of former JBoss AS. Oracle has never commercially supported GlassFish Server Open Source Edition builds. Tomitribe appears to be the exception to the rule, offering commercial support for Apache TomEE. Fact #5 - WebLogic and GlassFish share several Java EE implementations It has been no secret that although GlassFish and WebLogic share some JSR implementations (as stated in the The Aquarium announcement: JPA, JSF, WebSockets, CDI, Bean Validation, JAX-WS, JAXB, and WS-AT) and WebLogic understands GlassFish deployment descriptors, they are not from the same codebase. Fact #6 - WebLogic is not for GlassFish what JBoss EAP is for WildFly WebLogic is closed-source offering. It is commercialized through a license-based plus support fee model. OGS although from an Open Source code, has had the same commercial model as WebLogic. Still, one cannot compare GlassFish/WebLogic to WildFly/JBoss EAP. It is simply not the same case, since Oracle has had two different products from different codebases. The comparison should be limited to GlassFish Open Source / Oracle GlassFish Server versus WildFly / JBoss EAP. But the message now is much clear: Oracle will commercially support only the proprietary product WebLogic, and invest on GlassFish Server Open Source Edition as the reference implementation for the Java EE platform and future Java EE 8, as a developer-friendly community distribution, and encourages community participation through Adopt a JSR and contributions to GlassFish. In comparison Oracle's decision has pretty much the same goal as to when IBM killed support for Websphere Community Edition; and to when Red Hat decided to change the name of JBoss Community Edition to WildFly, simplifying and clarifying marketing message and leaving the commercial field wide open to JBoss EAP only. Oracle can now, as any other vendor has already been doing, focus on only one commercial offer. Some users are saying they will now move to WildFly, but it is important to note that Red Hat does not offer commercial support for WildFly builds. Although the future JBoss EAP versions will come from the same codebase as WildFly, the builds will definitely not be the same, nor sharing 100% of their functionalities and bug fixes. This means there will be no company running a WildFly build in production with support from Red Hat. This discussion has also raised an important and interesting information: Oracle offers a free for developers OTN License for WebLogic. For other environments this is different, but please note this is the same policy Red Hat applies to JBoss EAP, as stated in their download page and terms. Oracle had the same policy for OGS. TL;DR; GlassFish Server Open Source Edition isn’t dead. Current and new OGS 2.x/3.x customers will continue to have support (respecting LSP). WebLogic is not necessarily more expensive than OGS. Oracle will focus on one commercially supported Java EE application server, like other vendors also limit themselves to support one build/product only. Community builds are hardly supported. Commercially supported builds of Open Source products are not exactly from the same codebase as community builds. What's next for GlassFish and the Java EE community? There are conversations in place to tackle some of the community desires, most of them stated by Markus Eisele in his blog post. We will keep you posted.

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• Azure Diagnostics: The Bad, The Ugly, and a Better Way

  - by jasont

  If you’re a .Net web developer today, no doubt you’ve enjoyed watching Windows Azure grow up over the past couple of years. The platform has scaled, stabilized (mostly), and added on a slew of great (and sometimes overdue) features. What was once just an endpoint to host a solution, developers today have tremendous flexibility and options in the platform. Organizations are building new solutions and offerings on the platform, and others have, or are in the process of, migrating existing applications out of their own data centers into the Azure cloud. Whether new application development or migrating legacy, every development shop and IT organization needs to monitor their applications in the cloud, the same as they do on premises. Azure Diagnostics has some capabilities, but what I constantly hear from users is that it’s either (a) not enough, or (b) too cumbersome to set up. Today, Stackify is happy to announce that we fully support Azure deployments, just the same as your on-premises deployments. Let’s take a look below and compare and contrast the options. Azure Diagnostics Let’s crack open the Windows Azure documentation on Azure Diagnostics and see just how easy it is to use. The high level steps are:   Step 1: Import the Diagnostics Oh, I’ve already deployed my app without the diagnostics module. Guess I can’t do anything until I do this and re-deploy. Step 2: Configure the Diagnostics (and multiple sub-steps) Do I want it all? Or just pieces of it? Whoops, forgot to include a specific performance counter, I guess I’ll have to deploy again. Wait a minute… I have to specifically code these performance counters into my role’s OnStart() method, compile and deploy again? And query and consume it myself? Step 3: (Optional) Permanently store diagnostic data Lucky for me, Azure storage has gotten pretty cheap. But how often should I move the data into storage? I want to see real-time data, so I guess that’s out now as well. Step 4: (Optional) View stored diagnostic data Optional? Of course I want to see it. Conveniently, Microsoft recommends 3 tools to do this with. Un-conveniently, none of these are web based and they all just give you access to raw data, and very little charting or real-time intelligence. Just….. data. Nevermind that one product seems to have gotten stale since a recent acquisition, and doesn’t even have screenshots!   So, let’s summarize: lots of diagnostics data is available, but think realistically. Think Dev Ops. What happens when you are in the middle of a major production performance issue and you don’t have the diagnostics you need? You are redeploying an application (and thankfully you have a great branching strategy, so you feel perfectly safe just willy-nilly launching code into prod, don’t you?) to get data, then shipping it to storage, and then digging through that data to find a needle in a haystack. Would you like to be able to troubleshoot a performance issue in the middle of the night, or on a weekend, from your iPad or home computer’s web browser? Forget it: the best you get is this spark line in the Azure portal. If it’s real pointy, you probably have an issue; but since there is no alert based on a threshold your customers have likely already let you know. And high CPU, Memory, I/O, or Network doesn’t tell you anything about where the problem is. The Better Way – Stackify Stackify supports application and server monitoring in real time, all through a great web interface. All of the things that Azure Diagnostics provides, Stackify provides for your on-premises deployments, and you don’t need to know ahead of time that you’ll need it. It’s always there, it’s always on. Azure deployments are essentially no different than on-premises. It’s a Windows Server (or Linux) in the cloud. It’s behind a different firewall than your corporate servers. That’s it. Stackify can provide the same powerful tools to your Azure deployments in two simple steps. Step 1 Add a startup task to your web or worker role and deploy. If you can’t deploy and need it right now, no worries! Remote Desktop to the Azure instance and you can execute a Powershell script to download / install Stackify.   Step 2 Log in to your account at www.stackify.com and begin monitoring as much as you want, as often as you want and see the results instantly. WMI? It’s there Event Viewer? You’ve got it. File System Access? Yes, please! Would love to make sure my web.config is correct.   IIS / App Pool Info? Yep. You can even restart it. Running Services? All of them. Start and Stop them to your heart’s content. SQL Database access? You bet’cha. Alerts and Notification? Of course! You should know before your customers let you know. … and so much more.   Conclusion Microsoft has shown, consistently, that they love developers, developers, developers. What every developer needs to realize from this is that they’ve given you a canvas, which is exactly what Azure is. It’s great infrastructure that is readily available, easy to manage, and fairly cost effective. However, the tooling is your responsibility. What you get, at best, is bare bones. App and server diagnostics should be available when you need them. While we, as developers, try to plan for and think of everything ahead of time, there will come times where we need to get data that just isn’t available. And having to go through a lot of cumbersome steps to get that data, and then have to find a friendlier way to consume it…. well, that just doesn’t make a lot of sense to me. I’d rather spend my time writing and developing features and completing bug fixes for my applications, than to be writing code to monitor and diagnose.

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• DRY and SRP

  - by Timothy Klenke

  Originally posted on: http://geekswithblogs.net/TimothyK/archive/2014/06/11/dry-and-srp.aspxKent Beck’s XP Simplicity Rules (aka Four Rules of Simple Design) are a prioritized list of rules that when applied to your code generally yield a great design.  As you’ll see from the above link the list has slightly evolved over time.  I find today they are usually listed as: All Tests Pass Don’t Repeat Yourself (DRY) Express Intent Minimalistic These are prioritized.  If your code doesn’t work (rule 1) then everything else is forfeit.  Go back to rule one and get the code working before worrying about anything else. Over the years the community have debated whether the priority of rules 2 and 3 should be reversed.  Some say a little duplication in the code is OK as long as it helps express intent.  I’ve debated it myself.  This recent post got me thinking about this again, hence this post.   I don’t think it is fair to compare “Expressing Intent” against “DRY”.  This is a comparison of apples to oranges.  “Expressing Intent” is a principal of code quality.  “Repeating Yourself” is a code smell.  A code smell is merely an indicator that there might be something wrong with the code.  It takes further investigation to determine if a violation of an underlying principal of code quality has actually occurred. For example “using nouns for method names”, “using verbs for property names”, or “using Booleans for parameters” are all code smells that indicate that code probably isn’t doing a good job at expressing intent.  They are usually very good indicators.  But what principle is the code smell of Duplication pointing to and how good of an indicator is it? Duplication in the code base is bad for a couple reasons.  If you need to make a change and that needs to be made in a number of locations it is difficult to know if you have caught all of them.  This can lead to bugs if/when one of those locations is overlooked.  By refactoring the code to remove all duplication there will be left with only one place to change, thereby eliminating this problem. With most projects the code becomes the single source of truth for a project.  If a production code base is inconsistent with a five year old requirements or design document the production code that people are currently living with is usually declared as the current reality (or truth).  Requirement or design documents at this age in a project life cycle are usually of little value. Although comparing production code to external documentation is usually straight forward, duplication within the code base muddles this declaration of truth.  When code is duplicated small discrepancies will creep in between the two copies over time.  The question then becomes which copy is correct?  As different factions debate how the software should work, trust in the software and the team behind it erodes. The code smell of Duplication points to a violation of the “Single Source of Truth” principle.  Let me define that as: A stakeholder’s requirement for a software change should never cause more than one class to change. Violation of the Single Source of Truth principle will always result in duplication in the code.  However, the inverse is not always true.  Duplication in the code does not necessarily indicate that there is a violation of the Single Source of Truth principle. To illustrate this, let’s look at a retail system where the system will (1) send a transaction to a bank and (2) print a receipt for the customer.  Although these are two separate features of the system, they are closely related.  The reason for printing the receipt is usually to provide an audit trail back to the bank transaction.  Both features use the same data:  amount charged, account number, transaction date, customer name, retail store name, and etcetera.  Because both features use much of the same data, there is likely to be a lot of duplication between them.  This duplication can be removed by making both features use the same data access layer. Then start coming the divergent requirements.  The receipt stakeholder wants a change so that the account number has the last few digits masked out to protect the customer’s privacy.  That can be solve with a small IF statement whilst still eliminating all duplication in the system.  Then the bank wants to take a picture of the customer as well as capture their signature and/or PIN number for enhanced security.  Then the receipt owner wants to pull data from a completely different system to report the customer’s loyalty program point total. After a while you realize that the two stakeholders have somewhat similar, but ultimately different responsibilities.  They have their own reasons for pulling the data access layer in different directions.  Then it dawns on you, the Single Responsibility Principle: There should never be more than one reason for a class to change. In this example we have two stakeholders giving two separate reasons for the data access class to change.  It is clear violation of the Single Responsibility Principle.  That’s a problem because it can often lead the project owner pitting the two stakeholders against each other in a vein attempt to get them to work out a mutual single source of truth.  But that doesn’t exist.  There are two completely valid truths that the developers need to support.  How is this to be supported and honour the Single Responsibility Principle?  The solution is to duplicate the data access layer and let each stakeholder control their own copy. The Single Source of Truth and Single Responsibility Principles are very closely related.  SST tells you when to remove duplication; SRP tells you when to introduce it.  They may seem to be fighting each other, but really they are not.  The key is to clearly identify the different responsibilities (or sources of truth) over a system.  Sometimes there is a single person with that responsibility, other times there are many.  This can be especially difficult if the same person has dual responsibilities.  They might not even realize they are wearing multiple hats. In my opinion Single Source of Truth should be listed as the second rule of simple design with Express Intent at number three.  Investigation of the DRY code smell should yield to the proper application SST, without violating SRP.  When necessary leave duplication in the system and let the class names express the different people that are responsible for controlling them.  Knowing all the people with responsibilities over a system is the higher priority because you’ll need to know this before you can express it.  Although it may be a code smell when there is duplication in the code, it does not necessarily mean that the coder has chosen to be expressive over DRY or that the code is bad.

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• Create and Backup Multiple Profiles in Google Chrome

  - by Asian Angel

  Other browsers such as Firefox and SeaMonkey allow you to have multiple profiles but not Chrome…at least not until now. If you want to use multiple profiles and create backups for them then join us as we look at Google Chrome Backup. Note: There is a paid version of this program available but we used the free version for our article. Google Chrome Backup in Action During the installation process you will run across this particular window. It will have a default user name filled in as shown here…you will not need to do anything except click on Next to continue installing the program. When you start the program for the first time this is what you will see. Your default Chrome Profile will already be visible in the window. A quick look at the Profile Menu… In the Tools Menu you can go ahead and disable the Start program at Windows Startup setting…the only time that you will need the program running is if you are creating or restoring a profile. When you create a new profile the process will start with this window. You can access an Advanced Options mode if desired but most likely you will not need it. Here is a look at the Advanced Options mode. It is mainly focused on adding Switches to the new Chrome Shortcut. The drop-down menu for the Switches available… To create your new profile you will need to choose: A profile location A profile name (as you type/create the profile name it will automatically be added to the Profile Path) Make certain that the Create a new shortcut to access new profile option is checked For our example we decided to try out the Disable plugins switch option… Click OK to create the new profile. Once you have created your new profile, you will find a new shortcut on the Desktop. Notice that the shortcut’s name will be Google Chrome + profile name that you chose. Note: On our system we were able to move the new shortcut to the “Start Menu” without problems. Clicking on our new profile’s shortcut opened up a fresh and clean looking instance of Chrome. Just out of curiosity we did decide to check the shortcut to see if the Switch set up correctly. Unfortunately it did not in this instance…so your mileage with the Switches may vary. This was just a minor quirk and nothing to get excited or upset over…especially considering that you can create multiple profiles so easily. After opening up our default profile of Chrome you can see the individual profile icons (New & Default in order) sitting in the Taskbar side-by-side. And our two profiles open at the same time on our Desktop… Backing Profiles Up For the next part of our tests we decided to create a backup for each of our profiles. Starting the wizard will allow you to choose between creating or restoring a profile. Note: To create or restore a backup click on Run Wizard. When you reach the second part of the process you can go with the Backup default profile option or choose a particular one from a drop-down list using the Select a profile to backup option. We chose to backup the Default Profile first… In the third part of the process you will need to select a location to save the profile to. Once you have selected the location you will see the Target Path as shown here. You can choose your own name for the backup file…we decided to go with the default name instead since it contained the backup’s calendar date. A very nice feature is the ability to have the cache cleared before creating the backup. We clicked on Yes…choose the option that best suits your needs. Once you have chosen either Yes or No the backup will then be created. Click Finish to complete the process. The backup file for our Default Profile at 14.0 MB in size. And the backup file for our Chrome Fresh Profile…2.81 MB. Restoring Profiles For the final part of our tests we decided to do a Restore. Select Restore and click Next to get the process started. In the second step you will need to browse for the Profile Backup File (and select the desired profile if you have created multiples). For our example we decided to overwrite the original Default Profile with the Chrome Fresh Profile. The third step lets you choose where to restore the chosen profile to…you can go with the Default Profile or choose one from the drop-down list using the Restore to a selected profile option. The final step will get you on your way to restoring the chosen profile. The program will conduct a check regarding the previous/old profile and ask if you would like to proceed with overwriting it. Definitely nice in case you change your mind at the last moment. Clicking Yes will finish the restoration. The only other odd quirk that we noticed while using the program was that the Next Button did not function after restoring the profile. You can easily get around the problem by clicking to close the window. Which one is which? After the restore process we had identical twins. Conclusion If you have been looking for a way to create multiple profiles in Google Chrome, then you might want to add this program to your system. Links Download Google Chrome Backup Similar Articles Productive Geek Tips Backup and Restore Firefox Profiles EasilyBackup Different Browsers Easily with FavBackupBackup Your Browser with the New FavBackupStupid Geek Tricks: Compare Your Browser’s Memory Usage with Google ChromeHow to Make Google Chrome Your Default Browser TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Acronis Online Backup DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows Tech Fanboys Field Guide Check these Awesome Chrome Add-ons iFixit Offers Gadget Repair Manuals Online Vista style sidebar for Windows 7 Create Nice Charts With These Web Based Tools Track Daily Goals With 42Goals

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• Emtel Knowledge Series - Q2/2014

  From Cyber Island to Smart Mauritius Cyber Island? Smart Mauritius? - What is Emtel talking about? "With the majority of the population living in urban environments today, the concept of "Smart Cities" has become an urgent necessity. "Smart Cities" refer to an urban transformation which, by using latest ICT technologies makes cities more efficient. Many Governments are setting out ambitious plans to build the cities of the future based on massive connectivity, high bandwidth communications, intelligent sensors and analysis of huge volumes of data. Various researches have shown four key enablers for smart city success - Government leadership, suitable technology infrastructure, solid public-private partnerships and engaged citizens. It is around these enabling factors that telecoms companies can play a vital role in assisting governments to deliver on the smart city vision." The Emtel Knowledge Series goes in compliance with Emtel's 25th anniversary celebrations throughout the year and the master of ceremony, Kim Andersen, mentioned that there will be more upcoming events on a quarterly base. As a representative of the Mauritius Software Craftsmanship Community (MSCC) there was absolutely no hesitation to join in again. Following my visit to the first Emtel Knowledge Series workshop back in February this year, it was great to have another opportunity to meet and exchange with technology experts. But quite frankly what is it with those buzz words... As far as I remember and how it was mentioned "Cyber Island" is an old initiative from around 2005/2006 which has been refreshed in 2010. It implies the empowerment of Information & Communication Technologies (ICT) as an essential factor of growth by the government here in Mauritius. Actually, the first promotional period of Cyber Island brought me here but that's another story. The venue and its own problems Like last time the event was organised and held at the Conference Hall at Cyber Tower I in Ebene. As I've been working there for some years, I know about the frustrating situation of finding a proper parking. So, does Smart Island include better solutions for the search of parking spaces? Maybe, let's see whether I will be able to answer that question at the end of the article. Anyway, after circling around the tower almost two times, I finally got a decent space to put the car, without risking to get a ticket or damage actually. International speakers and their experience Once again, Emtel did a great job to get international expertise onto the stage to share their experience and vision on this kind of embarkment. Personally, I really appreciated the fact they were speakers of global reach and could provide own-experience knowledge. Johan Gott spoke about the fundamental change that the Swedish government ignited in order to move their society and workers' environment away from heavy industry towards a knowledge-based approach. Additionally, we spoke about the effort and transformation of New York City into a greener and more efficient Smart City. Given modern technology he also advised that any kind of available Big Data should be opened to the general public - this openness would provide a playground for anyone to garner new ideas and most probably solid solutions of which no one else thought about before. Emtel Knowledge Series on moving from Cyber Island to Smart Mauritus Later during the afternoon that exact statement regarding openness to and transparency of government-owned Big Data has been emphasised again by the Danish speaker Kim Andersen and his former colleague Mika Jantunen from Finland. Mika continued to underline the important role of the government to provide a solid foundation for a knowledge-based society and mentioned that Finnish citizens have a constitutional right to broadband connectivity. Next to free higher (tertiary) education Finland already produced a good number of innovations, among them are: First country to grant voting rights to women Free higher education Constitutional right to broadband connectivity Nokia Linux Angry Birds Sauna and others...  General access to internet via broadband and/or mobile connectivity is surely a key factor towards Smart Cities, or better said Smart Mauritius given the area dimensions and size of population. CTO Paul Valette gave the audience a brief overview of the essential role that Emtel will have to move Mauritius forward towards a knowledge-based and innovation-driven environment for its citizen. What I have seen looks really promising and with recently published information that Mauritians have 127% of mobile capacity - meaning more than 1 mobile, smartphone or tablet per person - it will be crucial to have the right infrastructure for these connected devices. How would it be possible to achieve a knowledge-based society? YouTube to the rescue!Seriously, gaining more knowledge will require to have fast access to educational course material as explained by Dr Kaviraj Sukon, General Director of the Open University of Mauritius. According to him a good number of high-profile universities in the world have opened their course libraries to the general public, among them EDX, Coursera and Open University. Nowadays, you're actually able and enabled to learn for and earn a BSc or even MSc certification on your own pace - no need to attend classed on campus. It was really impressive to see the number of available hours - more than enough for a life-long learning experience! {loadposition content_adsense} Networking in the name of MSCC As briefly mentioned above I was about to combine two approaches for this workshop. Of course, getting latest information and updates on Emtel services available, especially for my business here on the west coast of the island, but also to meet and greet new people for the MSCC. And I think it was very positive on both sides. Let me quickly describe some of the key aspects that happened during the day: Met with Arnaud Meslier and Kellie, both Microsoft to swap latest information on IT events. Hereby, I got an invite to Microsoft Windows Phone 8.1 Dev Camp. Got in touch with Arvin Lockee, Emtel to check our options to meet with the data team, and seizing the opportunity to have a visiting tour at the Emtel Data Centre. Had a great chat with Avinash Meetoo, Knowledge 7, Kim Andersen and Mika Jantunen about the situation of teaching and learning in general and specifically in the private sector here in Mauritius. Additionally, a number of various other interesting chats... Once again, I'm catching up on a couple of business cards in order to provide more background information about the MSCC, and to create a better awareness of MSCC within the local IT businesses. There is more to come soon!  Resume of the day The number of attendees during this event has been doubled or even tripled this time. The whole organisation has been improved massively and the combination of presentation and summarizing panel discussions was better than during the previous workshop back in February. Overall, once again a well-organised workshop and I'm already looking forward to join the next workshop in Q3. Update End of July we finally managed to visit the Emtel Data Centre in Arsenal. It was an interesting opportunity for some of our MSCC members.

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• DTracing TCP congestion control

  - by user12820842

  In a previous post, I showed how we can use DTrace to probe TCP receive and send window events. TCP receive and send windows are in effect both about flow-controlling how much data can be received - the receive window reflects how much data the local TCP is prepared to receive, while the send window simply reflects the size of the receive window of the peer TCP. Both then represent flow control as imposed by the receiver. However, consider that without the sender imposing flow control, and a slow link to a peer, TCP will simply fill up it's window with sent segments. Dealing with multiple TCP implementations filling their peer TCP's receive windows in this manner, busy intermediate routers may drop some of these segments, leading to timeout and retransmission, which may again lead to drops. This is termed congestion, and TCP has multiple congestion control strategies. We can see that in this example, we need to have some way of adjusting how much data we send depending on how quickly we receive acknowledgement - if we get ACKs quickly, we can safely send more segments, but if acknowledgements come slowly, we should proceed with more caution. More generally, we need to implement flow control on the send side also. Slow Start and Congestion Avoidance From RFC2581, let's examine the relevant variables: "The congestion window (cwnd) is a sender-side limit on the amount of data the sender can transmit into the network before receiving an acknowledgment (ACK). Another state variable, the slow start threshold (ssthresh), is used to determine whether the slow start or congestion avoidance algorithm is used to control data transmission" Slow start is used to probe the network's ability to handle transmission bursts both when a connection is first created and when retransmission timers fire. The latter case is important, as the fact that we have effectively lost TCP data acts as a motivator for re-probing how much data the network can handle from the sending TCP. The congestion window (cwnd) is initialized to a relatively small value, generally a low multiple of the sending maximum segment size. When slow start kicks in, we will only send that number of bytes before waiting for acknowledgement. When acknowledgements are received, the congestion window is increased in size until cwnd reaches the slow start threshold ssthresh value. For most congestion control algorithms the window increases exponentially under slow start, assuming we receive acknowledgements. We send 1 segment, receive an ACK, increase the cwnd by 1 MSS to 2*MSS, send 2 segments, receive 2 ACKs, increase the cwnd by 2*MSS to 4*MSS, send 4 segments etc. When the congestion window exceeds the slow start threshold, congestion avoidance is used instead of slow start. During congestion avoidance, the congestion window is generally updated by one MSS for each round-trip-time as opposed to each ACK, and so cwnd growth is linear instead of exponential (we may receive multiple ACKs within a single RTT). This continues until congestion is detected. If a retransmit timer fires, congestion is assumed and the ssthresh value is reset. It is reset to a fraction of the number of bytes outstanding (unacknowledged) in the network. At the same time the congestion window is reset to a single max segment size. Thus, we initiate slow start until we start receiving acknowledgements again, at which point we can eventually flip over to congestion avoidance when cwnd ssthresh. Congestion control algorithms differ most in how they handle the other indication of congestion - duplicate ACKs. A duplicate ACK is a strong indication that data has been lost, since they often come from a receiver explicitly asking for a retransmission. In some cases, a duplicate ACK may be generated at the receiver as a result of packets arriving out-of-order, so it is sensible to wait for multiple duplicate ACKs before assuming packet loss rather than out-of-order delivery. This is termed fast retransmit (i.e. retransmit without waiting for the retransmission timer to expire). Note that on Oracle Solaris 11, the congestion control method used can be customized. See here for more details. In general, 3 or more duplicate ACKs indicate packet loss and should trigger fast retransmit . It's best not to revert to slow start in this case, as the fact that the receiver knew it was missing data suggests it has received data with a higher sequence number, so we know traffic is still flowing. Falling back to slow start would be excessive therefore, so fast recovery is used instead. Observing slow start and congestion avoidance The following script counts TCP segments sent when under slow start (cwnd ssthresh). #!/usr/sbin/dtrace -s #pragma D option quiet tcp:::connect-request / start[args[1]-cs_cid] == 0/ { start[args[1]-cs_cid] = 1; } tcp:::send / start[args[1]-cs_cid] == 1 && args[3]-tcps_cwnd tcps_cwnd_ssthresh / { @c["Slow start", args[2]-ip_daddr, args[4]-tcp_dport] = count(); } tcp:::send / start[args[1]-cs_cid] == 1 && args[3]-tcps_cwnd args[3]-tcps_cwnd_ssthresh / { @c["Congestion avoidance", args[2]-ip_daddr, args[4]-tcp_dport] = count(); } As we can see the script only works on connections initiated since it is started (using the start[] associative array with the connection ID as index to set whether it's a new connection (start[cid] = 1). From there we simply differentiate send events where cwnd ssthresh (congestion avoidance). Here's the output taken when I accessed a YouTube video (where rport is 80) and from an FTP session where I put a large file onto a remote system. # dtrace -s tcp_slow_start.d ^C ALGORITHM RADDR RPORT #SEG Slow start 10.153.125.222 20 6 Slow start 138.3.237.7 80 14 Slow start 10.153.125.222 21 18 Congestion avoidance 10.153.125.222 20 1164 We see that in the case of the YouTube video, slow start was exclusively used. Most of the segments we sent in that case were likely ACKs. Compare this case - where 14 segments were sent using slow start - to the FTP case, where only 6 segments were sent before we switched to congestion avoidance for 1164 segments. In the case of the FTP session, the FTP data on port 20 was predominantly sent with congestion avoidance in operation, while the FTP session relied exclusively on slow start. For the default congestion control algorithm - "newreno" - on Solaris 11, slow start will increase the cwnd by 1 MSS for every acknowledgement received, and by 1 MSS for each RTT in congestion avoidance mode. Different pluggable congestion control algorithms operate slightly differently. For example "highspeed" will update the slow start cwnd by the number of bytes ACKed rather than the MSS. And to finish, here's a neat oneliner to visually display the distribution of congestion window values for all TCP connections to a given remote port using a quantization. In this example, only port 80 is in use and we see the majority of cwnd values for that port are in the 4096-8191 range. # dtrace -n 'tcp:::send { @q[args[4]-tcp_dport] = quantize(args[3]-tcps_cwnd); }' dtrace: description 'tcp:::send ' matched 10 probes ^C 80 value ------------- Distribution ------------- count -1 | 0 0 |@@@@@@ 5 1 | 0 2 | 0 4 | 0 8 | 0 16 | 0 32 | 0 64 | 0 128 | 0 256 | 0 512 | 0 1024 | 0 2048 |@@@@@@@@@ 8 4096 |@@@@@@@@@@@@@@@@@@@@@@@@@@ 23 8192 | 0

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• Fun with Aggregates

  - by Paul White

  There are interesting things to be learned from even the simplest queries.  For example, imagine you are given the task of writing a query to list AdventureWorks product names where the product has at least one entry in the transaction history table, but fewer than ten. One possible query to meet that specification is: SELECT p.Name FROM Production.Product AS p JOIN Production.TransactionHistory AS th ON p.ProductID = th.ProductID GROUP BY p.ProductID, p.Name HAVING COUNT_BIG(*) < 10; That query correctly returns 23 rows (execution plan and data sample shown below): The execution plan looks a bit different from the written form of the query: the base tables are accessed in reverse order, and the aggregation is performed before the join.  The general idea is to read all rows from the history table, compute the count of rows grouped by ProductID, merge join the results to the Product table on ProductID, and finally filter to only return rows where the count is less than ten. This ‘fully-optimized’ plan has an estimated cost of around 0.33 units.  The reason for the quote marks there is that this plan is not quite as optimal as it could be – surely it would make sense to push the Filter down past the join too?  To answer that, let’s look at some other ways to formulate this query.  This being SQL, there are any number of ways to write logically-equivalent query specifications, so we’ll just look at a couple of interesting ones.  The first query is an attempt to reverse-engineer T-SQL from the optimized query plan shown above.  It joins the result of pre-aggregating the history table to the Product table before filtering: SELECT p.Name FROM ( SELECT th.ProductID, cnt = COUNT_BIG(*) FROM Production.TransactionHistory AS th GROUP BY th.ProductID ) AS q1 JOIN Production.Product AS p ON p.ProductID = q1.ProductID WHERE q1.cnt < 10; Perhaps a little surprisingly, we get a slightly different execution plan: The results are the same (23 rows) but this time the Filter is pushed below the join!  The optimizer chooses nested loops for the join, because the cardinality estimate for rows passing the Filter is a bit low (estimate 1 versus 23 actual), though you can force a merge join with a hint and the Filter still appears below the join.  In yet another variation, the < 10 predicate can be ‘manually pushed’ by specifying it in a HAVING clause in the “q1” sub-query instead of in the WHERE clause as written above. The reason this predicate can be pushed past the join in this query form, but not in the original formulation is simply an optimizer limitation – it does make efforts (primarily during the simplification phase) to encourage logically-equivalent query specifications to produce the same execution plan, but the implementation is not completely comprehensive. Moving on to a second example, the following query specification results from phrasing the requirement as “list the products where there exists fewer than ten correlated rows in the history table”: SELECT p.Name FROM Production.Product AS p WHERE EXISTS ( SELECT * FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID HAVING COUNT_BIG(*) < 10 ); Unfortunately, this query produces an incorrect result (86 rows): The problem is that it lists products with no history rows, though the reasons are interesting.  The COUNT_BIG(*) in the EXISTS clause is a scalar aggregate (meaning there is no GROUP BY clause) and scalar aggregates always produce a value, even when the input is an empty set.  In the case of the COUNT aggregate, the result of aggregating the empty set is zero (the other standard aggregates produce a NULL).  To make the point really clear, let’s look at product 709, which happens to be one for which no history rows exist: -- Scalar aggregate SELECT COUNT_BIG(*) FROM Production.TransactionHistory AS th WHERE th.ProductID = 709;   -- Vector aggregate SELECT COUNT_BIG(*) FROM Production.TransactionHistory AS th WHERE th.ProductID = 709 GROUP BY th.ProductID; The estimated execution plans for these two statements are almost identical: You might expect the Stream Aggregate to have a Group By for the second statement, but this is not the case.  The query includes an equality comparison to a constant value (709), so all qualified rows are guaranteed to have the same value for ProductID and the Group By is optimized away. In fact there are some minor differences between the two plans (the first is auto-parameterized and qualifies for trivial plan, whereas the second is not auto-parameterized and requires cost-based optimization), but there is nothing to indicate that one is a scalar aggregate and the other is a vector aggregate.  This is something I would like to see exposed in show plan so I suggested it on Connect.  Anyway, the results of running the two queries show the difference at runtime: The scalar aggregate (no GROUP BY) returns a result of zero, whereas the vector aggregate (with a GROUP BY clause) returns nothing at all.  Returning to our EXISTS query, we could ‘fix’ it by changing the HAVING clause to reject rows where the scalar aggregate returns zero: SELECT p.Name FROM Production.Product AS p WHERE EXISTS ( SELECT * FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID HAVING COUNT_BIG(*) BETWEEN 1 AND 9 ); The query now returns the correct 23 rows: Unfortunately, the execution plan is less efficient now – it has an estimated cost of 0.78 compared to 0.33 for the earlier plans.  Let’s try adding a redundant GROUP BY instead of changing the HAVING clause: SELECT p.Name FROM Production.Product AS p WHERE EXISTS ( SELECT * FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID GROUP BY th.ProductID HAVING COUNT_BIG(*) < 10 ); Not only do we now get correct results (23 rows), this is the execution plan: I like to compare that plan to quantum physics: if you don’t find it shocking, you haven’t understood it properly :)  The simple addition of a redundant GROUP BY has resulted in the EXISTS form of the query being transformed into exactly the same optimal plan we found earlier.  What’s more, in SQL Server 2008 and later, we can replace the odd-looking GROUP BY with an explicit GROUP BY on the empty set: SELECT p.Name FROM Production.Product AS p WHERE EXISTS ( SELECT * FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID GROUP BY () HAVING COUNT_BIG(*) < 10 ); I offer that as an alternative because some people find it more intuitive (and it perhaps has more geek value too).  Whichever way you prefer, it’s rather satisfying to note that the result of the sub-query does not exist for a particular correlated value where a vector aggregate is used (the scalar COUNT aggregate always returns a value, even if zero, so it always ‘EXISTS’ regardless which ProductID is logically being evaluated). The following query forms also produce the optimal plan and correct results, so long as a vector aggregate is used (you can probably find more equivalent query forms): WHERE Clause SELECT p.Name FROM Production.Product AS p WHERE ( SELECT COUNT_BIG(*) FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID GROUP BY () ) < 10; APPLY SELECT p.Name FROM Production.Product AS p CROSS APPLY ( SELECT NULL FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID GROUP BY () HAVING COUNT_BIG(*) < 10 ) AS ca (dummy); FROM Clause SELECT q1.Name FROM ( SELECT p.Name, cnt = ( SELECT COUNT_BIG(*) FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID GROUP BY () ) FROM Production.Product AS p ) AS q1 WHERE q1.cnt < 10; This last example uses SUM(1) instead of COUNT and does not require a vector aggregate…you should be able to work out why :) SELECT q.Name FROM ( SELECT p.Name, cnt = ( SELECT SUM(1) FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID ) FROM Production.Product AS p ) AS q WHERE q.cnt < 10; The semantics of SQL aggregates are rather odd in places.  It definitely pays to get to know the rules, and to be careful to check whether your queries are using scalar or vector aggregates.  As we have seen, query plans do not show in which ‘mode’ an aggregate is running and getting it wrong can cause poor performance, wrong results, or both. © 2012 Paul White Twitter: @SQL_Kiwi email: [email protected]

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• Checking who is connected to your server, with PowerShell.

  - by Fatherjack

  There are many occasions when, as a DBA, you want to see who is connected to your SQL Server, along with how they are connecting and what sort of activities they are carrying out. I’m going to look at a couple of ways of getting this information and compare the effort required and the results achieved of each. SQL Server comes with a couple of stored procedures to help with this sort of task – sp_who and its undocumented counterpart sp_who2. There is also the pumped up version of these called sp_whoisactive, written by Adam Machanic which does way more than these procedures. I wholly recommend you try it out if you don’t already know how it works. When it comes to serious interrogation of your SQL Server activity then it is absolutely indispensable. Anyway, back to the point of this blog, we are going to look at getting the information from sp_who2 for a remote server. I wrote this Powershell script a week or so ago and was quietly happy with it for a while. I’m relatively new to Powershell so forgive both my rather low threshold for entertainment and the fact that something so simple is a moderate achievement for me. $Server = 'SERVERNAME' $SMOServer = New-Object Microsoft.SQLServer.Management.SMO.Server $Server # connection and query stuff         $ConnectionStr = "Server=$Server;Database=Master;Integrated Security=True" $Query = "EXEC sp_who2" $Connection = new-object system.Data.SQLClient.SQLConnection $Table = new-object "System.Data.DataTable" $Connection.connectionstring = $ConnectionStr try{ $Connection.open() $Command = $Connection.CreateCommand() $Command.commandtext = $Query $result = $Command.ExecuteReader() $Table.Load($result) } catch{ # Show error $error[0] | format-list -Force } $Title = "Data access processes (" + $Table.Rows.Count + ")" $Table | Out-GridView -Title $Title $Connection.close() So this is pretty straightforward, create an SMO object that represents our chosen server, define a connection to the database and a table object for the results when we get them, execute our query over the connection, load the results into our table object and then, if everything is error free display these results to the PowerShell grid viewer. The query simply gets the results of ‘EXEC sp_who2′ for us. Depending on how many connections there are will influence how long the query runs. The grid viewer lets me sort and search the results so it can be a pretty handy way to locate troublesome connections. Like I say, I was quite pleased with this, it seems a pretty simple script and was working well for me, I have added a few parameters to control the output and give me more specific details but then I see a script that uses the $SMOServer object itself to provide the process information and saves having to define the connection object and query specifications. $Server = 'SERVERNAME' $SMOServer = New-Object Microsoft.SQLServer.Management.SMO.Server $Server $Processes = $SMOServer.EnumProcesses() $Title = "SMO processes (" + $Processes.Rows.Count + ")" $Processes | Out-GridView -Title $Title Create the SMO object of our server and then call the EnumProcesses method to get all the process information from the server. Staggeringly simple! The results are a little different though. Some columns are the same and we can see the same basic information so my first thought was to which runs faster – so that I can get my results more quickly and also so that I place less stress on my server(s). PowerShell comes with a great way of testing this – the Measure-Command function. All you have to do is wrap your piece of code in Measure-Command {[your code here]} and it will spit out the time taken to execute the code. So, I placed both of the above methods of getting SQL Server process connections in two Measure-Command wrappers and pressed F5! The Powershell console goes blank for a while as the code is executed internally when Measure-Command is used but the grid viewer windows appear and the console shows this. You can take the output from Measure-Command and format it for easier reading but in a simple comparison like this we can simply cross refer the TotalMilliseconds values from the two result sets to see how the two methods performed. The query execution method (running EXEC sp_who2 ) is the first set of timings and the SMO EnumProcesses is the second. I have run these on a variety of servers and while the results vary from execution to execution I have never seen the SMO version slower than the other. The difference has varied and the time for both has ranged from sub-second as we see above to almost 5 seconds on other systems. This difference, I would suggest is partly due to the cost overhead of having to construct the data connection and so on where as the SMO EnumProcesses method has the connection to the server already in place and just needs to call back the process information. There is also the difference in the data sets to consider. Let’s take a look at what we get and where the two methods differ Query execution method (sp_who2) SMO EnumProcesses Description - Urn What looks like an XML or JSON representation of the server name and the process ID SPID Spid The process ID Status Status The status of the process Login Login The login name of the user executing the command HostName Host The name of the computer where the  process originated BlkBy BlockingSpid The SPID of a process that is blocking this one DBName Database The database that this process is connected to Command Command The type of command that is executing CPUTime Cpu The CPU activity related to this process DiskIO - The Disk IO activity related to this process LastBatch - The time the last batch was executed from this process. ProgramName Program The application that is facilitating the process connection to the SQL Server. SPID1 - In my experience this is always the same value as SPID. REQUESTID - In my experience this is always 0 - Name In my experience this is always the same value as SPID and so could be seen as analogous to SPID1 from sp_who2 - MemUsage An indication of the memory used by this process but I don’t know what it is measured in (bytes, Kb, Mb…) - IsSystem True or False depending on whether the process is internal to the SQL Server instance or has been created by an external connection requesting data. - ExecutionContextID In my experience this is always 0 so could be analogous to REQUESTID from sp_who2. Please note, these are my own very brief descriptions of these columns, detail can be found from MSDN for columns in the sp_who results here http://msdn.microsoft.com/en-GB/library/ms174313.aspx. Where the columns are common then I would use that description, in other cases then the information returned is purely for interpretation by the reader. Rather annoyingly both result sets have useful information that the other doesn’t. sp_who2 returns Disk IO and LastBatch information which is really useful but the SMO processes method give you IsSystem and MemUsage which have their place in fault diagnosis methods too. So which is better? On reflection I think I prefer to use the sp_who2 method primarily but knowing that the SMO Enumprocesses method is there when I need it is really useful and I’m sure I’ll use it regularly. I’m OK with the fact that it is the slower method because Measure-Command has shown me how close it is to the other option and that it really isn’t a large enough margin to matter.

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• elffile: ELF Specific File Identification Utility

  - by user9154181

  Solaris 11 has a new standard user level command, /usr/bin/elffile. elffile is a variant of the file utility that is focused exclusively on linker related files: ELF objects, archives, and runtime linker configuration files. All other files are simply identified as "non-ELF". The primary advantage of elffile over the existing file utility is in the area of archives — elffile examines the archive members and can produce a summary of the contents, or per-member details. The impetus to add elffile to Solaris came from the effort to extend the format of Solaris archives so that they could grow beyond their previous 32-bit file limits. That work introduced a new archive symbol table format. Now that there was more than one possible format, I thought it would be useful if the file utility could identify which format a given archive is using, leading me to extend the file utility: % cc -c ~/hello.c % ar r foo.a hello.o % file foo.a foo.a: current ar archive, 32-bit symbol table % ar r -S foo.a hello.o % file foo.a foo.a: current ar archive, 64-bit symbol table In turn, this caused me to think about all the things that I would like the file utility to be able to tell me about an archive. In particular, I'd like to be able to know what's inside without having to unpack it. The end result of that train of thought was elffile. Much of the discussion in this article is adapted from the PSARC case I filed for elffile in December 2010: PSARC 2010/432 elffile Why file Is No Good For Archives And Yet Should Not Be Fixed The standard /usr/bin/file utility is not very useful when applied to archives. When identifying an archive, a user typically wants to know 2 things: Is this an archive? Presupposing that the archive contains objects, which is by far the most common use for archives, what platform are the objects for? Are they for sparc or x86? 32 or 64-bit? Some confusing combination from varying platforms? The file utility provides a quick answer to question (1), as it identifies all archives as "current ar archive". It does nothing to answer the more interesting question (2). To answer that question, requires a multi-step process: Extract all archive members Use the file utility on the extracted files, examine the output for each file in turn, and compare the results to generate a suitable summary description. Remove the extracted files It should be easier and more efficient to answer such an obvious question. It would be reasonable to extend the file utility to examine archive contents in place and produce a description. However, there are several reasons why I decided not to do so: The correct design for this feature within the file utility would have file examine each archive member in turn, applying its full abilities to each member. This would be elegant, but also represents a rather dramatic redesign and re-implementation of file. Archives nearly always contain nothing but ELF objects for a single platform, so such generality in the file utility would be of little practical benefit. It is best to avoid adding new options to standard utilities for which other implementations of interest exist. In the case of the file utility, one concern is that we might add an option which later appears in the GNU version of file with a different and incompatible meaning. Indeed, there have been discussions about replacing the Solaris file with the GNU version in the past. This may or may not be desirable, and may or may not ever happen. Either way, I don't want to preclude it. Examining archive members is an O(n) operation, and can be relatively slow with large archives. The file utility is supposed to be a very fast operation. I decided that extending file in this way is overkill, and that an investment in the file utility for better archive support would not be worth the cost. A solution that is more narrowly focused on ELF and other linker related files is really all that we need. The necessary code for doing this already exists within libelf. All that is missing is a small user-level wrapper to make that functionality available at the command line. In that vein, I considered adding an option for this to the elfdump utility. I examined elfdump carefully, and even wrote a prototype implementation. The added code is small and simple, but the conceptual fit with the rest of elfdump is poor. The result complicates elfdump syntax and documentation, definite signs that this functionality does not belong there. And so, I added this functionality as a new user level command. The elffile Command The syntax for this new command is elffile [-s basic | detail | summary] filename... Please see the elffile(1) manpage for additional details. To demonstrate how output from elffile looks, I will use the following files: FileDescription configA runtime linker configuration file produced with crle dwarf.oAn ELF object /etc/passwdA text file mixed.aArchive containing a mixture of ELF and non-ELF members mixed_elf.aArchive containing ELF objects for different machines not_elf.aArchive containing no ELF objects same_elf.aArchive containing a collection of ELF objects for the same machine. This is the most common type of archive. The file utility identifies these files as follows: % file config dwarf.o /etc/passwd mixed.a mixed_elf.a not_elf.a same_elf.a config: Runtime Linking Configuration 64-bit MSB SPARCV9 dwarf.o: ELF 64-bit LSB relocatable AMD64 Version 1 /etc/passwd: ascii text mixed.a: current ar archive, 32-bit symbol table mixed_elf.a: current ar archive, 32-bit symbol table not_elf.a: current ar archive same_elf.a: current ar archive, 32-bit symbol table By default, elffile uses its "summary" output style. This output differs from the output from the file utility in 2 significant ways: Files that are not an ELF object, archive, or runtime linker configuration file are identified as "non-ELF", whereas the file utility attempts further identification for such files. When applied to an archive, the elffile output includes a description of the archive's contents, without requiring member extraction or other additional steps. Applying elffile to the above files: % elffile config dwarf.o /etc/passwd mixed.a mixed_elf.a not_elf.a same_elf.a config: Runtime Linking Configuration 64-bit MSB SPARCV9 dwarf.o: ELF 64-bit LSB relocatable AMD64 Version 1 /etc/passwd: non-ELF mixed.a: current ar archive, 32-bit symbol table, mixed ELF and non-ELF content mixed_elf.a: current ar archive, 32-bit symbol table, mixed ELF content not_elf.a: current ar archive, non-ELF content same_elf.a: current ar archive, 32-bit symbol table, ELF 64-bit LSB relocatable AMD64 Version 1 The output for same_elf.a is of particular interest: The vast majority of archives contain only ELF objects for a single platform, and in this case, the default output from elffile answers both of the questions about archives posed at the beginning of this discussion, in a single efficient step. This makes elffile considerably more useful than file, within the realm of linker-related files. elffile can produce output in two other styles, "basic", and "detail". The basic style produces output that is the same as that from 'file', for linker-related files. The detail style produces per-member identification of archive contents. This can be useful when the archive contents are not homogeneous ELF object, and more information is desired than the summary output provides: % elffile -s detail mixed.a mixed.a: current ar archive, 32-bit symbol table mixed.a(dwarf.o): ELF 32-bit LSB relocatable 80386 Version 1 mixed.a(main.c): non-ELF content mixed.a(main.o): ELF 64-bit LSB relocatable AMD64 Version 1 [SSE]

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• Why do we (really) program to interfaces?

  - by Kyle Burns

  One of the earliest lessons I was taught in Enterprise development was "always program against an interface".  This was back in the VB6 days and I quickly learned that no code would be allowed to move to the QA server unless my business objects and data access objects each are defined as an interface and have a matching implementation class.  Why?  "It's more reusable" was one answer.  "It doesn't tie you to a specific implementation" a slightly more knowing answer.  And let's not forget the discussion ending "it's a standard".  The problem with these responses was that senior people didn't really understand the reason we were doing the things we were doing and because of that, we were entirely unable to realize the intent behind the practice - we simply used interfaces and had a bunch of extra code to maintain to show for it. It wasn't until a few years later that I finally heard the term "Inversion of Control".  Simply put, "Inversion of Control" takes the creation of objects that used to be within the control (and therefore a responsibility of) of your component and moves it to some outside force.  For example, consider the following code which follows the old "always program against an interface" rule in the manner of many corporate development shops: 1: ICatalog catalog = new Catalog(); 2: Category[] categories = catalog.GetCategories(); In this example, I met the requirement of the rule by declaring the variable as ICatalog, but I didn't hit "it doesn't tie you to a specific implementation" because I explicitly created an instance of the concrete Catalog object.  If I want to test the functionality of the code I just wrote I have to have an environment in which Catalog can be created along with any of the resources upon which it depends (e.g. configuration files, database connections, etc) in order to test my functionality.  That's a lot of setup work and one of the things that I think ultimately discourages real buy-in of unit testing in many development shops. So how do I test my code without needing Catalog to work?  A very primitive approach I've seen is to change the line the instantiates catalog to read: 1: ICatalog catalog = new FakeCatalog();   once the test is run and passes, the code is switched back to the real thing.  This obviously poses a huge risk for introducing test code into production and in my opinion is worse than just keeping the dependency and its associated setup work.  Another popular approach is to make use of Factory methods which use an object whose "job" is to know how to obtain a valid instance of the object.  Using this approach, the code may look something like this: 1: ICatalog catalog = CatalogFactory.GetCatalog();   The code inside the factory is responsible for deciding "what kind" of catalog is needed.  This is a far better approach than the previous one, but it does make projects grow considerably because now in addition to the interface, the real implementation, and the fake implementation(s) for testing you have added a minimum of one factory (or at least a factory method) for each of your interfaces.  Once again, developers say "that's too complicated and has me writing a bunch of useless code" and quietly slip back into just creating a new Catalog and chalking any test failures up to "it will probably work on the server". This is where software intended specifically to facilitate Inversion of Control comes into play.  There are many libraries that take on the Inversion of Control responsibilities in .Net and most of them have many pros and cons.  From this point forward I'll discuss concepts from the standpoint of the Unity framework produced by Microsoft's Patterns and Practices team.  I'm primarily focusing on this library because it questions about it inspired this posting. At Unity's core and that of most any IoC framework is a catalog or registry of components.  This registry can be configured either through code or using the application's configuration file and in the most simple terms says "interface X maps to concrete implementation Y".  It can get much more complicated, but I want to keep things at the "what does it do" level instead of "how does it do it".  The object that exposes most of the Unity functionality is the UnityContainer.  This object exposes methods to configure the catalog as well as the Resolve<T> method which is used to obtain an instance of the type represented by T.  When using the Resolve<T> method, Unity does not necessarily have to just "new up" the requested object, but also can track dependencies of that object and ensure that the entire dependency chain is satisfied. There are three basic ways that I have seen Unity used within projects.  Those are through classes directly using the Unity container, classes requiring injection of dependencies, and classes making use of the Service Locator pattern. The first usage of Unity is when classes are aware of the Unity container and directly call its Resolve method whenever they need the services advertised by an interface.  The up side of this approach is that IoC is utilized, but the down side is that every class has to be aware that Unity is being used and tied directly to that implementation. Many developers don't like the idea of as close a tie to specific IoC implementation as is represented by using Unity within all of your classes and for the most part I agree that this isn't a good idea.  As an alternative, classes can be designed for Dependency Injection.  Dependency Injection is where a force outside the class itself manipulates the object to provide implementations of the interfaces that the class needs to interact with the outside world.  This is typically done either through constructor injection where the object has a constructor that accepts an instance of each interface it requires or through property setters accepting the service providers.  When using dependency, I lean toward the use of constructor injection because I view the constructor as being a much better way to "discover" what is required for the instance to be ready for use.  During resolution, Unity looks for an injection constructor and will attempt to resolve instances of each interface required by the constructor, throwing an exception of unable to meet the advertised needs of the class.  The up side of this approach is that the needs of the class are very clearly advertised and the class is unaware of which IoC container (if any) is being used.  The down side of this approach is that you're required to maintain the objects passed to the constructor as instance variables throughout the life of your object and that objects which coordinate with many external services require a lot of additional constructor arguments (this gets ugly and may indicate a need for refactoring). The final way that I've seen and used Unity is to make use of the ServiceLocator pattern, of which the Patterns and Practices team has also provided a Unity-compatible implementation.  When using the ServiceLocator, your class calls ServiceLocator.Retrieve in places where it would have called Resolve on the Unity container.  Like using Unity directly, it does tie you directly to the ServiceLocator implementation and makes your code aware that dependency injection is taking place, but it does have the up side of giving you the freedom to swap out the underlying IoC container if necessary.  I'm not hugely concerned with hiding IoC entirely from the class (I view this as a "nice to have"), so the single biggest problem that I see with the ServiceLocator approach is that it provides no way to proactively advertise needs in the way that constructor injection does, allowing more opportunity for difficult to track runtime errors. This blog entry has not been intended in any way to be a definitive work on IoC, but rather as something to spur thought about why we program to interfaces and some ways to reach the intended value of the practice instead of having it just complicate your code.  I hope that it helps somebody begin or continue a journey away from being a "Cargo Cult Programmer".

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• Kubuntu 12.04 - Touchpad and keyboard stopped working at random

  - by StepTNT

  As in the title, I've got this problem with my Kubuntu 12.04. At first I've thought that the whole system was hung, but it happened again 5 minutes ago and, while the keyboard and the touchpad stopped working, the music was still playing, so I guess that's just an "input" problem, because the system was still working! Any solution? Is there some data that you need to know about my setup? EDIT: Added my lshw outout description: Notebook product: N53SV () vendor: ASUSTeK Computer Inc. version: 1.0 serial: B2N0AS17695408A width: 64 bits capabilities: smbios-2.6 dmi-2.6 vsyscall32 configuration: boot=normal chassis=notebook family=N uuid=8083F2DA-A43E-E081-3F3F-BCAEC55F8AA1 *-core description: Motherboard product: N53SV vendor: ASUSTeK Computer Inc. physical id: 0 version: 1.0 serial: BSN12345678901234567 slot: MIDDLE *-firmware description: BIOS vendor: American Megatrends Inc. physical id: 0 version: N53SV.214 date: 08/10/2011 size: 64KiB capacity: 2496KiB capabilities: pci upgrade shadowing cdboot bootselect edd int13floppy1200 int13floppy720 int13floppy2880 int5printscreen int9keyboard int14serial int17printer acpi usb smartbattery biosbootspecification *-cpu description: CPU product: Intel(R) Core(TM) i7-2630QM CPU @ 2.00GHz vendor: Intel Corp. physical id: 4 bus info: cpu@0 version: Intel(R) Core(TM) i7-2630QM CPU @ 2.00GHz serial: To Be Filled By O.E.M. slot: CPU 1 size: 800MHz capacity: 4GHz width: 64 bits clock: 100MHz capabilities: x86-64 fpu fpu_exception wp vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic popcnt tsc_deadline_timer xsave avx lahf_lm ida arat epb xsaveopt pln pts tpr_shadow vnmi flexpriority ept vpid cpufreq configuration: cores=4 enabledcores=1 threads=2 *-cache description: L1 cache physical id: 5 slot: L1-Cache size: 32KiB capacity: 32KiB capabilities: internal write-back instruction *-memory description: System Memory physical id: 40 slot: System board or motherboard size: 10GiB *-bank:0 description: SODIMM DDR3 Synchronous 1333 MHz (0,8 ns) product: 99U5428-040.A00LF vendor: Kingston physical id: 0 serial: 103C28C3 slot: ChannelA-DIMM0 size: 4GiB width: 64 bits clock: 1333MHz (0.8ns) *-bank:1 description: SODIMM DDR3 Synchronous 1333 MHz (0,8 ns) product: HMT325S6BFR8C-H9 vendor: Hynix/Hyundai physical id: 1 serial: 58383D1F slot: ChannelA-DIMM1 size: 2GiB width: 64 bits clock: 1333MHz (0.8ns) *-bank:2 description: SODIMM DDR3 Synchronous 1333 MHz (0,8 ns) product: HMT325S6BFR8C-H9 vendor: Hynix/Hyundai physical id: 2 serial: 58183D19 slot: ChannelB-DIMM0 size: 2GiB width: 64 bits clock: 1333MHz (0.8ns) *-bank:3 description: SODIMM DDR3 Synchronous 1333 MHz (0,8 ns) product: HMT325S6BFR8C-H9 vendor: Hynix/Hyundai physical id: 3 serial: 58183C8F slot: ChannelB-DIMM1 size: 2GiB width: 64 bits clock: 1333MHz (0.8ns) *-pci description: Host bridge product: 2nd Generation Core Processor Family DRAM Controller vendor: Intel Corporation physical id: 100 bus info: pci@0000:00:00.0 version: 09 width: 32 bits clock: 33MHz configuration: driver=agpgart-intel resources: irq:0 *-pci:0 description: PCI bridge product: Xeon E3-1200/2nd Generation Core Processor Family PCI Express Root Port vendor: Intel Corporation physical id: 1 bus info: pci@0000:00:01.0 version: 09 width: 32 bits clock: 33MHz capabilities: pci pm msi pciexpress normal_decode bus_master cap_list configuration: driver=pcieport resources: irq:40 ioport:d000(size=4096) memory:db000000-dc0fffff ioport:c0000000(size=301989888) *-generic UNCLAIMED description: Unassigned class product: Illegal Vendor ID vendor: Illegal Vendor ID physical id: 0 bus info: pci@0000:01:00.0 version: ff width: 32 bits clock: 66MHz capabilities: bus_master vga_palette cap_list configuration: latency=255 maxlatency=255 mingnt=255 resources: memory:db000000-dbffffff memory:c0000000-cfffffff memory:d0000000-d1ffffff ioport:d000(size=128) memory:dc000000-dc07ffff *-display description: VGA compatible controller product: 2nd Generation Core Processor Family Integrated Graphics Controller vendor: Intel Corporation physical id: 2 bus info: pci@0000:00:02.0 version: 09 width: 64 bits clock: 33MHz capabilities: msi pm vga_controller bus_master cap_list rom configuration: driver=i915 latency=0 resources: irq:47 memory:dc400000-dc7fffff memory:b0000000-bfffffff ioport:e000(size=64) *-communication description: Communication controller product: 6 Series/C200 Series Chipset Family MEI Controller #1 vendor: Intel Corporation physical id: 16 bus info: pci@0000:00:16.0 version: 04 width: 64 bits clock: 33MHz capabilities: pm msi bus_master cap_list configuration: driver=mei latency=0 resources: irq:48 memory:df00b000-df00b00f *-usb:0 description: USB controller product: 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #2 vendor: Intel Corporation physical id: 1a bus info: pci@0000:00:1a.0 version: 05 width: 32 bits clock: 33MHz capabilities: pm debug ehci bus_master cap_list configuration: driver=ehci_hcd latency=0 resources: irq:16 memory:df008000-df0083ff *-multimedia description: Audio device product: 6 Series/C200 Series Chipset Family High Definition Audio Controller vendor: Intel Corporation physical id: 1b bus info: pci@0000:00:1b.0 version: 05 width: 64 bits clock: 33MHz capabilities: pm msi pciexpress bus_master cap_list configuration: driver=snd_hda_intel latency=0 resources: irq:49 memory:df000000-df003fff *-pci:1 description: PCI bridge product: 6 Series/C200 Series Chipset Family PCI Express Root Port 1 vendor: Intel Corporation physical id: 1c bus info: pci@0000:00:1c.0 version: b5 width: 32 bits clock: 33MHz capabilities: pci pciexpress msi pm normal_decode bus_master cap_list configuration: driver=pcieport resources: irq:41 ioport:c000(size=4096) memory:de600000-deffffff ioport:d4200000(size=10485760) *-pci:2 description: PCI bridge product: 6 Series/C200 Series Chipset Family PCI Express Root Port 2 vendor: Intel Corporation physical id: 1c.1 bus info: pci@0000:00:1c.1 version: b5 width: 32 bits clock: 33MHz capabilities: pci pciexpress msi pm normal_decode bus_master cap_list configuration: driver=pcieport resources: irq:42 ioport:b000(size=4096) memory:ddc00000-de5fffff ioport:d3700000(size=10485760) *-network description: Wireless interface product: AR9285 Wireless Network Adapter (PCI-Express) vendor: Atheros Communications Inc. physical id: 0 bus info: pci@0000:03:00.0 logical name: wlan0 version: 01 serial: 48:5d:60:f2:2c:fd width: 64 bits clock: 33MHz capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless configuration: broadcast=yes driver=ath9k driverversion=3.2.0-24-generic firmware=N/A ip=192.168.1.6 latency=0 link=yes multicast=yes wireless=IEEE 802.11bgn resources: irq:17 memory:ddc00000-ddc0ffff *-pci:3 description: PCI bridge product: 6 Series/C200 Series Chipset Family PCI Express Root Port 4 vendor: Intel Corporation physical id: 1c.3 bus info: pci@0000:00:1c.3 version: b5 width: 32 bits clock: 33MHz capabilities: pci pciexpress msi pm normal_decode bus_master cap_list configuration: driver=pcieport resources: irq:43 ioport:a000(size=4096) memory:dd200000-ddbfffff ioport:d2c00000(size=10485760) *-usb description: USB controller product: FL1000G USB 3.0 Host Controller vendor: Fresco Logic physical id: 0 bus info: pci@0000:04:00.0 version: 04 width: 32 bits clock: 33MHz capabilities: pm msi pciexpress xhci bus_master cap_list configuration: driver=xhci_hcd latency=0 resources: irq:19 memory:dd200000-dd20ffff *-pci:4 description: PCI bridge product: 6 Series/C200 Series Chipset Family PCI Express Root Port 6 vendor: Intel Corporation physical id: 1c.5 bus info: pci@0000:00:1c.5 version: b5 width: 32 bits clock: 33MHz capabilities: pci pciexpress msi pm normal_decode bus_master cap_list configuration: driver=pcieport resources: irq:44 ioport:9000(size=4096) memory:dc800000-dd1fffff ioport:d2100000(size=10485760) *-network description: Ethernet interface product: RTL8111/8168B PCI Express Gigabit Ethernet controller vendor: Realtek Semiconductor Co., Ltd. physical id: 0 bus info: pci@0000:05:00.0 logical name: eth0 version: 06 serial: bc:ae:c5:5f:8a:a1 size: 10Mbit/s capacity: 1Gbit/s width: 64 bits clock: 33MHz capabilities: pm msi pciexpress msix vpd bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=half firmware=rtl_nic/rtl8168e-2.fw latency=0 link=no multicast=yes port=MII speed=10Mbit/s resources: irq:46 ioport:9000(size=256) memory:d2104000-d2104fff memory:d2100000-d2103fff *-usb:1 description: USB controller product: 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #1 vendor: Intel Corporation physical id: 1d bus info: pci@0000:00:1d.0 version: 05 width: 32 bits clock: 33MHz capabilities: pm debug ehci bus_master cap_list configuration: driver=ehci_hcd latency=0 resources: irq:23 memory:df007000-df0073ff *-isa description: ISA bridge product: HM65 Express Chipset Family LPC Controller vendor: Intel Corporation physical id: 1f bus info: pci@0000:00:1f.0 version: 05 width: 32 bits clock: 33MHz capabilities: isa bus_master cap_list configuration: latency=0 *-storage description: SATA controller product: 6 Series/C200 Series Chipset Family 6 port SATA AHCI Controller vendor: Intel Corporation physical id: 1f.2 bus info: pci@0000:00:1f.2 logical name: scsi0 logical name: scsi2 version: 05 width: 32 bits clock: 66MHz capabilities: storage msi pm ahci_1.0 bus_master cap_list emulated configuration: driver=ahci latency=0 resources: irq:45 ioport:e0b0(size=8) ioport:e0a0(size=4) ioport:e090(size=8) ioport:e080(size=4) ioport:e060(size=32) memory:df006000-df0067ff *-disk description: ATA Disk product: ST9750420AS vendor: Seagate physical id: 0 bus info: scsi@0:0.0.0 logical name: /dev/sda version: 0002 serial: 5WS0A7QR size: 698GiB (750GB) capabilities: partitioned partitioned:dos configuration: ansiversion=5 signature=e0c5913d *-volume:0 description: Windows FAT volume vendor: MSDOS5.0 physical id: 1 bus info: scsi@0:0.0.0,1 logical name: /dev/sda1 version: FAT32 serial: 4ce5-3acb size: 3004MiB capacity: 3004MiB capabilities: primary fat initialized configuration: FATs=2 filesystem=fat *-volume:1 description: EXT4 volume vendor: Linux physical id: 2 bus info: scsi@0:0.0.0,2 logical name: /dev/sda2 logical name: / version: 1.0 serial: c198cc2a-d86a-4460-a4d5-3fc0b21e439c size: 28GiB capacity: 28GiB capabilities: primary journaled extended_attributes large_files huge_files dir_nlink recover extents ext4 ext2 initialized configuration: created=2012-03-15 16:53:54 filesystem=ext4 lastmountpoint=/ modified=2012-05-02 18:52:04 mount.fstype=ext4 mount.options=rw,relatime,errors=remount-ro,user_xattr,acl,barrier=1,data=ordered mounted=2012-05-09 19:06:01 state=mounted *-volume:2 description: Windows NTFS volume physical id: 3 bus info: scsi@0:0.0.0,3 logical name: /dev/sda3 version: 3.1 serial: 4c1cdebc-ec09-2947-a3b5-c1f9f1cddc1c size: 152GiB capacity: 152GiB capabilities: primary bootable ntfs initialized configuration: clustersize=4096 created=2011-02-22 16:02:47 filesystem=ntfs label=OS state=clean *-volume:3 description: Extended partition physical id: 4 bus info: scsi@0:0.0.0,4 logical name: /dev/sda4 size: 514GiB capacity: 514GiB capabilities: primary extended partitioned partitioned:extended *-logicalvolume:0 description: Linux swap / Solaris partition physical id: 5 logical name: /dev/sda5 capacity: 10GiB capabilities: nofs *-logicalvolume:1 description: HPFS/NTFS partition physical id: 6 logical name: /dev/sda6 capacity: 504GiB *-cdrom description: DVD-RAM writer product: BD-MLT UJ240AS vendor: MATSHITA physical id: 1 bus info: scsi@2:0.0.0 logical name: /dev/cdrom logical name: /dev/cdrw logical name: /dev/dvd logical name: /dev/dvdrw logical name: /dev/sr0 version: 1.00 capabilities: removable audio cd-r cd-rw dvd dvd-r dvd-ram configuration: ansiversion=5 status=nodisc *-serial UNCLAIMED description: SMBus product: 6 Series/C200 Series Chipset Family SMBus Controller vendor: Intel Corporation physical id: 1f.3 bus info: pci@0000:00:1f.3 version: 05 width: 64 bits clock: 33MHz configuration: latency=0 resources: memory:df005000-df0050ff ioport:e040(size=32)

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• Master-slave vs. peer-to-peer archictecture: benefits and problems

  - by Ashok_Ora

  Normal 0 false false false EN-US X-NONE X-NONE Almost two decades ago, I was a member of a database development team that introduced adaptive locking. Locking, the most popular concurrency control technique in database systems, is pessimistic. Locking ensures that two or more conflicting operations on the same data item don’t “trample” on each other’s toes, resulting in data corruption. In a nutshell, here’s the issue we were trying to address. In everyday life, traffic lights serve the same purpose. They ensure that traffic flows smoothly and when everyone follows the rules, there are no accidents at intersections. As I mentioned earlier, the problem with typical locking protocols is that they are pessimistic. Regardless of whether there is another conflicting operation in the system or not, you have to hold a lock! Acquiring and releasing locks can be quite expensive, depending on how many objects the transaction touches. Every transaction has to pay this penalty. To use the earlier traffic light analogy, if you have ever waited at a red light in the middle of nowhere with no one on the road, wondering why you need to wait when there’s clearly no danger of a collision, you know what I mean. The adaptive locking scheme that we invented was able to minimize the number of locks that a transaction held, by detecting whether there were one or more transactions that needed conflicting eyou could get by without holding any lock at all. In many “well-behaved” workloads, there are few conflicts, so this optimization is a huge win. If, on the other hand, there are many concurrent, conflicting requests, the algorithm gracefully degrades to the “normal” behavior with minimal cost. We were able to reduce the number of lock requests per TPC-B transaction from 178 requests down to 2! Wow! This is a dramatic improvement in concurrency as well as transaction latency. The lesson from this exercise was that if you can identify the common scenario and optimize for that case so that only the uncommon scenarios are more expensive, you can make dramatic improvements in performance without sacrificing correctness. So how does this relate to the architecture and design of some of the modern NoSQL systems? NoSQL systems can be broadly classified as master-slave sharded, or peer-to-peer sharded systems. NoSQL systems with a peer-to-peer architecture have an interesting way of handling changes. Whenever an item is changed, the client (or an intermediary) propagates the changes synchronously or asynchronously to multiple copies (for availability) of the data. Since the change can be propagated asynchronously, during some interval in time, it will be the case that some copies have received the update, and others haven’t. What happens if someone tries to read the item during this interval? The client in a peer-to-peer system will fetch the same item from multiple copies and compare them to each other. If they’re all the same, then every copy that was queried has the same (and up-to-date) value of the data item, so all’s good. If not, then the system provides a mechanism to reconcile the discrepancy and to update stale copies. So what’s the problem with this? There are two major issues: First, IT’S HORRIBLY PESSIMISTIC because, in the common case, it is unlikely that the same data item will be updated and read from different locations at around the same time! For every read operation, you have to read from multiple copies. That’s a pretty expensive, especially if the data are stored in multiple geographically separate locations and network latencies are high. Second, if the copies are not all the same, the application has to reconcile the differences and propagate the correct value to the out-dated copies. This means that the application program has to handle discrepancies in the different versions of the data item and resolve the issue (which can further add to cost and operation latency). Resolving discrepancies is only one part of the problem. What if the same data item was updated independently on two different nodes (copies)? In that case, due to the asynchronous nature of change propagation, you might land up with different versions of the data item in different copies. In this case, the application program also has to resolve conflicts and then propagate the correct value to the copies that are out-dated or have incorrect versions. This can get really complicated. My hunch is that there are many peer-to-peer-based applications that don’t handle this correctly, and worse, don’t even know it. Imagine have 100s of millions of records in your database – how can you tell whether a particular data item is incorrect or out of date? And what price are you willing to pay for ensuring that the data can be trusted? Multiple network messages per read request? Discrepancy and conflict resolution logic in the application, and potentially, additional messages? All this overhead, when all you were trying to do was to read a data item. Wouldn’t it be simpler to avoid this problem in the first place? Master-slave architectures like the Oracle NoSQL Database handles this very elegantly. A change to a data item is always sent to the master copy. Consequently, the master copy always has the most current and authoritative version of the data item. The master is also responsible for propagating the change to the other copies (for availability and read scalability). Client drivers are aware of master copies and replicas, and client drivers are also aware of the “currency” of a replica. In other words, each NoSQL Database client knows how stale a replica is. This vastly simplifies the job of the application developer. If the application needs the most current version of the data item, the client driver will automatically route the request to the master copy. If the application is willing to tolerate some staleness of data (e.g. a version that is no more than 1 second out of date), the client can easily determine which replica (or set of replicas) can satisfy the request, and route the request to the most efficient copy. This results in a dramatic simplification in application logic and also minimizes network requests (the driver will only send the request to exactl the right replica, not many). So, back to my original point. A well designed and well architected system minimizes or eliminates unnecessary overhead and avoids pessimistic algorithms wherever possible in order to deliver a highly efficient and high performance system. If you’ve every programmed an Oracle NoSQL Database application, you’ll know the difference! /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;}

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• SQL Server Developer Tools &ndash; Codename Juneau vs. Red-Gate SQL Source Control

  - by Ajarn Mark Caldwell

  So how do the new SQL Server Developer Tools (previously code-named Juneau) stack up against SQL Source Control?  Read on to find out. At the PASS Community Summit a couple of weeks ago, it was announced that the previously code-named Juneau software would be released under the name of SQL Server Developer Tools with the release of SQL Server 2012.  This replacement for Database Projects in Visual Studio (also known in a former life as Data Dude) has some great new features.  I won’t attempt to describe them all here, but I will applaud Microsoft for making major improvements.  One of my favorite changes is the way database elements are broken down.  Previously every little thing was in its own file.  For example, indexes were each in their own file.  I always hated that.  Now, SSDT uses a pattern similar to Red-Gate’s and puts the indexes and keys into the same file as the overall table definition. Of course there are really cool features to keep your database model in sync with the actual source scripts, and the rename refactoring feature is now touted as being more than just a search and replace, but rather a “semantic-aware” search and replace.  Funny, it reminds me of SQL Prompt’s Smart Rename feature.  But I’m not writing this just to criticize Microsoft and argue that they are late to the party with this feature set.  Instead, I do see it as a viable alternative for folks who want all of their source code to be version controlled, but there are a couple of key trade-offs that you need to know about when you choose which tool set to use. First, the basics Both tool sets integrate with a wide variety of source control systems including the most popular: Subversion, GIT, Vault, and Team Foundation Server.  Both tools have integrated functionality to produce objects to upgrade your target database when you are ready (DACPACs in SSDT, integration with SQL Compare for SQL Source Control).  If you regularly live in Visual Studio or the Business Intelligence Development Studio (BIDS) then SSDT will likely be comfortable for you.  Like BIDS, SSDT is a Visual Studio Project Type that comes with SQL Server, and if you don’t already have Visual Studio installed, it will install the shell for you.  If you already have Visual Studio 2010 installed, then it will just add this as an available project type.  On the other hand, if you regularly live in SQL Server Management Studio (SSMS) then you will really enjoy the SQL Source Control integration from within SSMS.  Both tool sets store their database model in script files.  In SSDT, these are on your file system like other source files; in SQL Source Control, these are stored in the folder structure in your source control system, and you can always GET them to your file system if you want to browse them directly. For me, the key differentiating factors are 1) a single, unified check-in, and 2) migration scripts.  How you value those two features will likely make your decision for you. Unified Check-In If you do a continuous-integration (CI) style of development that triggers an automated build with unit testing on every check-in of source code, and you use Visual Studio for the rest of your development, then you will want to really consider SSDT.  Because it is just another project in Visual Studio, it can be added to your existing Solution, and you can then do a complete, or unified single check-in of all changes whether they are application or database changes.  This is simply not possible with SQL Source Control because it is in a different development tool (SSMS instead of Visual Studio) and there is no way to do one unified check-in between the two.  You CAN do really fast back-to-back check-ins, but there is the possibility that the automated build that is triggered from the first check-in will cause your unit tests to fail and the CI tool to report that you broke the build.  Of course, the automated build that is triggered from the second check-in which contains the “other half” of your changes should pass and so the amount of time that the build was broken may be very, very short, but if that is very, very important to you, then SQL Source Control just won’t work; you’ll have to use SSDT. Refactoring and Migrations If you work on a mature system, or on a not-so-mature but also not-so-well-designed system, where you want to refactor the database schema as you go along, but you can’t have data suddenly disappearing from your target system, then you’ll probably want to go with SQL Source Control.  As I wrote previously, there are a number of changes which you can make to your database that the comparison tools (both from Microsoft and Red Gate) simply cannot handle without the possibility (or probability) of data loss.  Currently, SSDT only offers you the ability to inject PRE and POST custom deployment scripts.  There is no way to insert your own script in the middle to override the default behavior of the tool.  In version 3.0 of SQL Source Control (Early Access version now available) you have that ability to create your own custom migration script to take the place of the commands that the tool would have done, and ensure the preservation of your data.  Or, even if the default tool behavior would have worked, but you simply know a better way then you can take control and do things your way instead of theirs. You Decide In the environment I work in, our automated builds are not triggered off of check-ins, but off of the clock (currently once per night) and so there is no point at which the automated build and unit tests will be triggered without having both sides of the development effort already checked-in.  Therefore having a unified check-in, while handy, is not critical for us.  As for migration scripts, these are critically important to us.  We do a lot of new development on systems that have already been in production for years, and it is not uncommon for us to need to do a refactoring of the database.  Because of the maturity of the existing system, that often involves data migrations or other additional SQL tasks that the comparison tools just can’t detect on their own.  Therefore, the ability to create a custom migration script to override the tool’s default behavior is very important to us.  And so, you can see why we will continue to use Red Gate SQL Source Control for the foreseeable future.

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• D2K to OA Framework Transition

  - by PRajkumar

  What is the difference between D2K form and OA Framework? It is a very innocent but important question for someone that desires to make transition from D2K to OA Framework. I hope you have already read and implemented OA Framework Getting Started. I will re-visit my own experience of implementing HelloWorld program in "OA Framework". When I implemented HelloWorld a year ago, I had no clue as to what I was doing & why I was doing those steps. I merely copied the steps from Oracle Tutorial without understanding them. Hence in this blog, I will try to explain in simple manner the meaning of OA Framework HelloWorld Program and compare the steps to D2K form [where possible]. To keep things simple, only basics will be discussed. Following key Steps were needed for HelloWorld Step 1 Create a new Workspace and a new Project as dictated by Oracle's tutorial. When defining project, you will specify a default package, which in this case was oracle.apps.ak.hello This means the following: - ak is the short name of the Application in Oracle           [means fnd_applications.short_name] hello is the name of your project Step 2 Next, you will create a OA Page within hello project Think OA Page as the fmx file itself in D2K. I am saying so because this page gets attached to the form function. This page will be created within hello project, hence the package name oracle.apps.ak.hello.webui Note the webui, it is a convention to have page in webui, means this page represents the Web User Interface You will assign the default AM [OAApplicationModule]. Think of AM "Connection Manager" and "Transaction State Manager" for your page          I can't co-relate this to anything in D2k, as there is no concept of Connection Pooling and that D2k is not stateless. Reason being that as soon as you kick off a D2K Form, it connects to a single session of Oracle and sticks to that single Oracle database session. So is not the case in OAF, hence AM is needed. Step 3 You create Region within the Page. ·         Region is what will store your fields. Text input fields will be of type messageTextInput. Think of Canvas in D2K. You can have nested regions. Stacked Canvas in D2K comes the closest to this component of OA Framework Step 4 Add a button to one of the nested regions The itemStyle should be submitButton, in case you want the page to be submitted when this button is clicked There is no WHEN-BUTTON-PRESSED trigger in OAF. In Framework, you will add a controller java code to handle events like Form Submit button clicks. JDeveloper generates the default code for you. Primarily two functions [should I call methods] will be created processRequest [for UI Rendering Handling] and processFormRequest          Think of processRequest as WHEN-NEW-FORM-INSTANCE, though processRequest is very restrictive. Note What is the difference between processRequest and processFormRequest? These two methods are available in the Default Controller class that gets created. processFormRequest This method is commonly used to react/respond to the event that has taken place, for example click of a button. Some examples are if(oapagecontext.getParameter("Cancel") != null) (Do your processing for Cancellation/ Rollback) if(oapagecontext.getParameter("Submit") != null) (Do your validations and commit here) if(oapagecontext.getParameter("Update") != null) (Do your validations and commit here) In the above three examples, you could be calling oapagecontext.forwardImmediately to re-direct the page navigation to some other page if needed. processRequest In this method, usually page rendering related code is written. Effectively, each GUI component is a bean that gets initialised during processRequest. Those who are familiar with D2K forms, something like pre-query may be written in this method. Step 5 In the controller to access the value in field "HelloName" the command is String userContent = pageContext.getParameter("HelloName"); In D2k, we used :block.field. In OAFramework, at submission of page, all the field values get passed into to OAPageContext object. Use getParameter to access the field value To set the value of the field, use OAMessageTextInputBean field HelloName = (OAMessageTextInputBean)webBean.findChildRecursive("HelloName"); fieldHelloName.setText(pageContext,"Setting the default value" ); Note when setting field value in controller: Note 1. Do not set the value in processFormRequest Note 2. If the field comes from View Object, then do not use setText in controller Note 3. For control fields [that are not based on View Objects], you can use setText to assign values in processRequest method Lets take some notes to expand beyond the HelloWorld Project Note 1 In D2K-forms we sort of created a Window, attached to Canvas, and then fields within that Canvas. However in OA Framework, think of Page being fmx/Window, think of Region being a Canvas, and fields being within Regions. This is not a formal/accurate understanding of analogy between D2k and Framework, but is close to being logical. Note 2 In D2k, your Forms fmb file was compiled to fmx. It was fmx file that was deployed on mid-tier. In case of OAF, your OA Page is nothing but a XML file. We call this MDS [meta data]. Whatever name you give to "Page" in OAF, an XML file of the same name gets created. This xml file must then be loaded into database by using XML Importer command. Note 3 Apart from MDS XML file, almost everything else is merely deployed to your mid-tier. Usually this is underneath $JAVA_TOP/oracle/apps/../.. All java files will go underneath java top/oracle/apps/../.. etc. Note 4 When building tutorial, ignore the steps for setting "Attribute Sets". These are not mandatory. Oracle might just have developed their tutorials without including these. Think of these like Visual Attributes of D2K forms Note 5 Controller is where you will write any java code in OA Framework. You can create a Controller per Page or have a different Controller for each of the Regions with the same Page. Note 6 In the method processFormRequest of the Controller, you can access the values of the page by using notation pageContext.getParameter("<fieldname here>"). This method processFormRequest is executed when the OAF Screen/Page is submitted by click of a button. Note 7 Inside the controller, all the Database Related interactions for example interaction with View Objects happen via Application Module. But why so? Because Application Module Manages the transaction state of the Application. OAApplicationModuleImpl oaapplicationmoduleimpl = OAApplicationModuleImpl)oapagecontext.getApplicationModule(oawebbean); OADBTransaction oadbtransaction = OADBTransaction)oaapplicationmoduleimpl.getDBTransaction(); Note 8 In D2K, we have control block or a block based on database view. Similarly, in OA Framework, if the field does not have view Object attached, then it is like a control field. Hence in HelloWorld example, field HelloName is a control field [in D2K terminology]. A view Object can either be based on a view/table, synonym or on a SQL statement. Note 9 I wish to access the fields in multi record block that is based on view Object. Can I do this in Controller? Sure you can. To traverse through those records, do the below ·         Get the reference to the View Object using (OAViewObject)oapagecontext.getApplicationModule(oawebbean).findViewObject("VO Name Here") ·         Loop through the records in View Objects using count returned from oaviewobject.getFetchedRowCount() ·         For each record, fetch the value of the fields within the loop as oracle.jbo.Row row = oaviewobject.getRowAtRangeIndex(loop index here); (String)row.getAttribute("Column name of VO here ");

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• 5 Lessons learnt in localization / multi language support in WPF

  - by MarkPearl

  For the last few months I have been secretly working away at the second version of an application that we initially released a few years ago. It’s called MaxCut and it is a free panel/cut optimizer for the woodwork, glass and metal industry. One of the motivations for writing MaxCut was to get an end to end experience in developing an application for general consumption. From the early days of v1 of MaxCut I would get the odd email thanking me for the software and then listing a few suggestions on how to improve it. Two of the most dominant suggestions that we received were… Support for imperial measurements (the original program only supported the metric system) Multi language support (we had someone who volunteered to translate the program into Japanese for us). I am not going to dive into the Imperial to Metric support in todays blog post, but I would like to cover a few brief lessons we learned in adding support for multi-language functionality in the software. I have sectioned them below under different lessons. Lesson 1 – Build multi-language support in from the start So the first lesson I learnt was if you know you are going to do multi language support – build it in from the very beginning! One of the power points of WPF/Silverlight is data binding in XAML and so while it wasn’t to painful to retro fit multi language support into the programing, it was still time consuming and a bit tedious to go through mounds and mounds of views and would have been a minor job to have implemented this while the form was being designed. Lesson 2 – Accommodate for varying word lengths using Grids The next lesson was a little harder to learn and was learnt a bit further down the road in the development cycle. We developed everything in English, assuming that other languages would have similar character length words for equivalent meanings… don’t!. A word that is short in your language may be of varying character lengths in other languages. Some language like Dutch and German allow for concatenation of nouns which has the potential to create really long words. We picked up a few places where our views had been structured incorrectly so that if a word was to long it would get clipped off or cut out. To get around this we began using the WPF grid extensively with column widths that would automatically expand if they needed to. Generally speaking the grid replacement got round this hurdle, and if in future you have a choice between a stack panel or a grid – think twice before going for the easier option… often the grid will be a bit more work to setup, but will be more flexible. Lesson 3 – Separate the separators Our initial run through moving the words to a resource dictionary led us to make what I thought was one potential mistake. If we had a label like the following… “length : “ In the resource dictionary we put it as a single entry. This is fine until you start using a word more than once. For instance in our scenario we used the word “length’ frequently. with different variations of the word with grammar and separators included in the resource we ended up having what I would consider a bloated dictionary. When we removed the separators from the words and put them as their own resources we saw a dramatic reduction in dictionary size… so something that looked like this… “length : “ “length. “ “length?” Was reduced to… “length” “:” “?” “.” While this may not seem like a reduction at first glance, consider that the separators “:?.” are used everywhere and suddenly you see a real reduction in bloat. Lesson 4 – Centralize the Language Dictionary This lesson was learnt at the very end of the project after we had already had a release candidate out in the wild. Because our translations would be done on a volunteer basis and remotely, we wanted it to be really simple for someone to translate our program into another language. As a common design practice we had tiered the application so that we had a business logic layer, a ui layer, etc. The problem was in several of these layers we had resource files specific for that layer. What this resulted in was us having multiple resource files that we would need to send to our translators. To add to our problems, some of the wordings were duplicated in different resource files, which would result in additional frustration from our translators as they felt they were duplicating work. Eventually the workaround was to make a separate project in VS2010 with just the language translations. We then exposed the dictionary as public within this project and made it as a reference to the other projects within the solution. This solved out problem as now we had a central dictionary and could remove any duplication's. Lesson 5 – Make a dummy translation file to test that you haven’t missed anything The final lesson learnt about multi language support in WPF was when checking if you had forgotten to translate anything in the inline code, make a test resource file with dummy data. Ideally you want the data for each word to be identical. In our instance we made one which had all the resource key values pointing to a value of test. This allowed us point the language file to our test resource file and very quickly browse through the program and see if we had missed any linking. The alternative to this approach is to have two language files and swap between the two while running the program to make sure that you haven’t missed anything, but the downside of dual language file approach is that it is much a lot harder spotting a mistake if everything is different – almost like playing Where’s Wally / Waldo. It is much easier spotting variance in uniformity – meaning when you put the “test’ keyword for everything, anything that didn’t say “test” stuck out like a sore thumb. So these are my top five lessons learnt on implementing multi language support in WPF. Feel free to make any suggestions in the comments section if you feel maybe something is more important than one of these or if I got it wrong!

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• Calculated Fields - Idiosyncracies

  - by PointsToShare

  © 2011 By: Dov Trietsch. All rights reserved Calculated Fields and some of their Idiosyncrasies Did you try to write a calculate field formula directly into the screen? Good Luck – You’ll need it! Calculated Fields are a sophisticated OOB feature of SharePoint, so you could think that they are best left to the end users – at least to the power users. But they reach their limits before the “Professionals “do, and the tough ones come back to us anyway. Back to business; the simpler the formula, the easier it is. Still, use your favorite editor to write it, then cut it and paste it to the ridiculously small window. What about complex formulae? Write them in steps! Here is a case in point and an idiosyncrasy or two. Our welders need to be certified and recertified every two years. Some of them are certifiable…., but I digress. To be certified you need to pass an eye exam, and two more tests – test A and test B. for each of those you have an expiry date. When renewed, each expiry date is advanced by two years from the date of renewal. My users wanted a visual clue so that when the supervisor looks at the list, she’ll have a KPI symbol telling her if anything expired (Red), is going to expire within the next 90 days (Yellow) or is not to be worried about (green). Not all the dates are filled and any blank date implies a complete lack of certification in the particular requirement. Obviously, I needed to figure the minimal of these 3 dates – a simple enough formula: =MIN([Date_EyeExam], {Date_TestA], [Date_TestB]). Aha! Here is idiosyncrasy #1. When one of the dates is a null, MIN(Date1, Date2) returns the non null date. Null is construed as “Far, far away”. The funny thing is that when you compare it to Today, the null is the lesser one. So a null it is less than today, but not when MIN is calculated. Now, to me the fact that the welder does not have an exam date, is synonymous with his exam being prehistoric, or at least past due. So here is what I did: Solution: Let’s set a blank date to 1/1/1800. How will we do that? Use the IF. IF([Field] rel relValue, TrueValue, FalseValue). rel is any relationship operator <, >, <=, >=, =, <>. If the field is related to the relValue as prescribed, the “IF” returns the TrueValue, otherwise it returns the FalseValue. Thus: =IF([SomeDate]="",1/1/1800,[SomeDate]) will return 1/1/1800 if the date is blank and the date itself if not. So, using this formula, if the welder missed an exam, the returned exam date will be far in the past. It would be nice if we could take such a formula and make it into a reusable function. Alas, here is a calculated field serious shortcoming: You cannot write subs and functions!! Aha, but we can use interim calculated fields! So let’s create 3 calculated fields as follows: 1: c_DateTestA as a calculated field of the date type, with the formula:  IF([Date_TestA]="",1/1/1800,[Date_TestA]) 2: c_DateTestB as a calculated field of the date type, with the formula:  IF([Date_TestB]="",1/1/1800,[Date_TestB]) 3: c_DateEyeExam as a calculated field of the date type, with the formula:  IF([Date_EyeExam]="",1/1/1800,[Date_EyeExam]) And now use these to get c_MinDate. This is again a calculated field of type date with the formula: MIN(c_DateTestA, cDateTestB, c_DateEyeExam) Note that I missed the square parentheses. In “properly named fields – where there are no embedded spaces, we don’t need the square parentheses. I actually strongly recommend using underscores in place of spaces in all the field names in your lists. Among other things, it makes using CAML much simpler. Now, we still need to apply the KPI to this minimal date. I am going to use the available KPI graphics that come with SharePoint and are always available in your 12 hive. "/_layouts/images/kpidefault-2.gif" is the Red KPI "/_layouts/images/kpidefault-1.gif" is the Yellow KPI "/_layouts/images/kpidefault-0.gif" is the Green KPI And here is the nested IF formula that will do the trick: =IF(c_MinDate<=Today,"/_layouts/images/kpidefault-2.gif", IF(cMinDate<Today+90,"/_layouts/images/kpidefault-1.gif","/_layouts/images/kpidefault-0.gif")) Nice! BUT when I tested, it did not work! This is Idiosyncrasy #2: A calculated field based on a calculated field based on a calculated field does not work. You have to stop at two levels! Back to the drawing board: We have to reduce by one level. How? We’ll eliminate the c_DateX items in the formula and replace them with the proper IF formulae. Notice that this needs to be done with precision. You are much better off in doing it in your favorite line editor, than inside the cramped space that SharePoint gives you. So here is the result: MIN(IF([Date_TestA]="",1/1/1800,[ Date_TestA]), IF([Date_TestB]="",1/1/1800,[ Date_TestB]), 1/1/1800), IF([Date_EyeExam]="",1/1/1800,[Date_EyeExam])) Note that I bolded the parentheses and painted them red. They have to match for this formula to work. Now we can leave the KPI formula as is and test again. This time with SUCCESS! Conclusion: build the inner functions first, and then embed them inside the outer formulae. Do this as long as necessary. Use your favorite line editor. Limit yourself to 2 levels. That’s all folks! Almost! As soon as I finished doing all of the above, my users added yet another level of complexity. They added another test, a test that must be passed, but never expires and asked for yet another KPI, this time in Black to denote that any test is not just past due, but altogether missing. I just finished this. Let’s hope it ends here! And OH, the formula  =IF(c_MinDate<=Today,"/_layouts/images/kpidefault-2.gif",IF(cMinDate<Today+90,"/_layouts/images/kpidefault-1.gif","/_layouts/images/kpidefault-0.gif")) Deals with “Today” and this is a subject deserving a discussion of its own!  That’s all folks?! (and this time I mean it)

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• HTG Explains: Should You Buy Extended Warranties?

  - by Chris Hoffman

  Buy something at an electronics store and you’ll be confronted by a pushy salesperson who insists you need an extended warranty. You’ll also see extended warranties pushed hard when shopping online. But are they worth it? There’s a reason stores push extended warranties so hard. They’re almost always pure profit for the store involved. An electronics store may live on razor-thin product margins and make big profits on extended warranties and overpriced HDMI cables. You’re Already Getting Multiple Warranties First, back up. The product you’re buying already includes a warranty. In fact, you’re probably getting several different types of warranties. Store Return and Exchange: Most electronics stores allow you to return a malfunctioning product within the first 15 or 30 days and they’ll provide you with a new one. The exact period of time will vary from store to store. If you walk out of the store with a defective product and have to swap it for a new one within the first few weeks, this should be easy. Manufacturer Warranty: A device’s manufacturer — whether the device is a laptop, a television, or a graphics card — offers their own warranty period. The manufacturer warranty covers you after the store refuses to take the product back and exchange it. The length of this warranty depends on the type of product. For example, a cheap laptop may only offer a one-year manufacturer warranty, while a more expensive laptop may offer a two-year warranty. Credit Card Warranty Extension: Many credit cards offer free extended warranties on products you buy with that credit card. Credit card companies will often give you an additional year of warranty. For example, if you buy a laptop with a two year warranty and it fails in the third year, you could then contact your credit card company and they’d cover the cost of fixing or replacing it. Check your credit card’s benefits and fine print for more information. Why Extended Warranties Are Bad You’re already getting a fairly long warranty period, especially if you have a credit card that offers you a free extended warranty — these are fairly common. If the product you get is a “lemon” and has a manufacturing error, it will likely fail pretty soon — well within your warranty period. The extended warranty matters after all your other warranties are exhausted. In the case of a laptop with a two-year warranty that you purchase with a credit card giving you a one-year warranty extension, your extended warranty will kick in three years after you purchase the laptop. In that many years, your current laptop will likely feel pretty old and laptops that are as good — or better — will likely be pretty cheap. If it’s a television, better television displays will be available at a lower price point. You’ll either want to upgrade to a newer model or you’ll be able to buy a new, just-as-good product for very cheap. You’ll only have to pay out-of-pocket if your device fails after the normal warranty period — in over two or three years for typical laptops purchased with a decent credit card. Save the money you would have spent on the warranty and put it towards a future upgrade. How Much Do Extended Warranties Cost? Let’s look at an example from a typical pushy retail outlet, Best Buy. We went to Best Buy’s website and found a pretty standard $600 Samsung laptop. This laptop comes with a one-year warranty period. If purchased with a fairly common credit card, you can easily get a two-year warranty period on this laptop without spending an additional penny. (Yes, such credit cards are available with no yearly fees.) During the check-out process, Best Buy tries to sell you a Geek Squad “Accidental Protection Plan.” To get an additional year of Best Buy’s extended warranty, you’d have to pay $324.98 for a “3-Year Accidental Protection Plan”. You’d basically be paying more than half the price of your laptop for an additional year of warranty — remember, the standard warranties would cover you anyway for the first two years. If this laptop did break sometime between two and three years from now, we wouldn’t be surprised if you could purchase a comparable laptop for about $325 anyway. And, if you don’t need to replace it, you’ve saved that money. Best Buy would object that this isn’t a standard extended warranty. It’s a supercharged warranty plan that will also provide coverage if you spill something on your laptop or drop it and break it. You just have to ask yourself a question. What are the odds that you’ll drop your laptop or spill something on it? They’re probably pretty low if you’re a typical human being. Is it worth spending more than half the price of the laptop just in case you’ll make an uncommon mistake? Probably not. There may be occasional exceptions to this — some Apple users swear by Apple’s AppleCare, for example — but you should generally avoid buying these things. There’s a reason stores are so pushy about extended warranties, and it’s not because they want to help protect you. It’s because they’re making lots of profit from these plans, and they’re making so much profit because they’re not a good deal for customers. Image Credit: Philip Taylor on Flickr     

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• Different Not Automatically Implies Better

  - by Alois Kraus

  Originally posted on: http://geekswithblogs.net/akraus1/archive/2013/11/05/154556.aspxRecently I was digging deeper why some WCF hosted workflow application did consume quite a lot of memory although it did basically only load a xaml workflow. The first tool of choice is Process Explorer or even better Process Hacker (has more options and the best feature copy&paste does work). The three most important numbers of a process with regards to memory are Working Set, Private Working Set and Private Bytes. Working set is the currently consumed physical memory (parts can be shared between processes e.g. loaded dlls which are read only) Private Working Set is the physical memory needed by this process which is not shareable Private Bytes is the number of non shareable which is only visible in the current process (e.g. all new, malloc, VirtualAlloc calls do create private bytes) When you have a bigger workflow it can consume under 64 bit easily 500MB for a 1-2 MB xaml file. This does not look very scalable. Under 64 bit the issue is excessive private bytes consumption and not the managed heap. The picture is quite different for 32 bit which looks a bit strange but it seems that the hosted VB compiler is a lot less memory hungry under 32 bit. I did try to repro the issue with a medium sized xaml file (400KB) which does contain 1000 variables and 1000 if which can be represented by C# code like this: string Var1; string Var2; ... string Var1000; if (!String.IsNullOrEmpty(Var1) ) { Console.WriteLine(“Var1”); } if (!String.IsNullOrEmpty(Var2) ) { Console.WriteLine(“Var2”); } ....   Since WF is based on VB.NET expressions you are bound to the hosted VB.NET compiler which does result in (x64) 140 MB of private bytes which is ca. 140 KB for each if clause which is quite a lot if you think about the actually present functionality. But there is hope. .NET 4.5 does allow now C# expressions for WF which is a major step forward for all C# lovers. I did create some simple patcher to “cross compile” my xaml to C# expressions. Lets look at the result: C# Expressions VB Expressions x86 x86 On my home machine I have only 32 bit which gives you quite exactly half of the memory consumption under 64 bit. C# expressions are 10 times more memory hungry than VB.NET expressions! I wanted to do more with less memory but instead it did consume a magnitude more memory. That is surprising to say the least. The workflow does initialize in about the same time under x64 and x86 where the VB code does it in 2s whereas the C# version needs 18s. Also nearly ten times slower. That is a too high price to pay for any bigger sized xaml workflow to convert from VB.NET to C# expressions. If I do reduce the number of expressions to 500 then it does need 400MB which is about half of the memory. It seems that the cost per if does rise linear with the number of total expressions in a xaml workflow.  Expression Language Cost per IF Startup Time C# 1000 Ifs x64 1,5 MB 18s C# 500 Ifs x64 750 KB 9s VB 1000 Ifs x64 140 KB 2s VB 500 Ifs x64 70 KB 1s Now we can directly compare two MS implementations. It is clear that the VB.NET compiler uses the same underlying structure but it has much higher offset compared to the highly inefficient C# expression compiler. I have filed a connect bug here with a harsher wording about recent advances in memory consumption. The funniest thing is that one MS employee did give an Azure AppFabric demo around early 2011 which was so slow that he needed to investigate with xperf. He was after startup time and the call stacks with regards to VB.NET expression compilation were remarkably similar. In fact I only found this post by googling for parts of my call stacks. … “C# expressions will be coming soon to WF, and that will have different performance characteristics than VB” … What did he know Jan 2011 what I did no know until today? ;-). He knew that C# expression will come but that they will not be automatically have better footprint. It is about time to fix that. In its current state C# expressions are not usable for bigger workflows. That also explains the headline for today. You can cheat startup time by prestarting workflows so that the demo looks nice and snappy but it does hurt scalability a lot since you do need much more memory than necessary. I did find the stacks by enabling virtual allocation tracking within XPerf which is still the best tool out there. But first you need to look at your process to check where the memory is hiding: For the C# Expression compiler you do not need xperf. You can directly dump the managed heap and check with a profiler of your choice. But if the allocations are happening on the Private Data ( VirtualAlloc ) you can find it with xperf. There is a nice video on channel 9 explaining VirtualAlloc tracking it in greater detail. If your data allocations are on the Heap it does mean that the C/C++ runtime did create a heap for you where all malloc, new calls do allocate from it. You can enable heap tracing with xperf and full call stack support as well which is doable via xperf like it is shown also on channel 9. Or you can use WPRUI directly: To make “Heap Usage” it work you need to set for your executable the tracing flags (before you start it). For example devenv.exe HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options\devenv.exe DWORD TracingFlags 1 Do not forget to disable it after you did complete profiling the process or it will impact the startup time quite a lot. You can with xperf attach directly to a running process and collect heap allocation information from a gone wild process. Very handy if you need to find out what a process was doing which has arrived in a funny state. “VirtualAlloc usage” does work without explicitly enabling stuff for a specific process and is always on machine wide. I had issues on my Windows 7 machines with the call stack collection and the latest Windows 8.1 Performance Toolkit. I was told that WPA from Windows 8.0 should work fine but I do not want to downgrade.

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• SOA Implementation Challenges

  Why do companies think that if they put up a web service that they are doing Service-Oriented Architecture (SOA)? Unfortunately, the IT and business world love to run on the latest hype or buzz words of which very few even understand the meaning. One of the largest issues companies have today as they consider going down the path of SOA, is the lack of knowledge regarding the architectural style and the over usage of the term SOA. So how do we solve this issue?I am sure most of you are thinking by now that you know what SOA is because you developed a few web services.  Isn’t that SOA, right? No, that is not SOA, but instead Just Another Web Service (JAWS). For us to better understand what SOA is let’s look at a few definitions.Douglas K. Bary defines service-oriented architecture as a collection of services. These services are enabled to communicate with each other in order to pass data or coordinating some activity with other services.If you look at this definition closely you will notice that Bary states that services communicate with each other. Let us compare this statement with my first statement regarding companies that claim to be doing SOA when they have just a collection of web services. In order for these web services to for an SOA application they need to be interdependent on one another forming some sort of architectural hierarchy. Just because a company has a few web services does not mean that they are all interconnected.SearchSOA from TechTarget.com states that SOA defines how two computing entities work collectively to enable one entity to perform a unit of work on behalf of another. Once again, just because a company has a few web services does not guarantee that they are even working together let alone if they are performing work for each other.SearchSOA also points out service interactions should be self-contained and loosely-coupled so that all interactions operate independent of each other.Of all the definitions regarding SOA Thomas Erl’s seems to shed the most light on this concept. He states that “SOA establishes an architectural model that aims to enhance the efficiency, agility, and productivity of an enterprise by positioning services as the primary means through which solution logic is represented in support of the realization of the strategic goals associated with service-oriented computing.” (Erl, 2011) Once again this definition proves that a collection of web services does not mean that a company is doing SOA. However, it does mean that a company has a collection of web services, and that is it.In order for a company to start to go down the path of SOA, they must take  a hard look at their existing business process while abstracting away any technology so that they can define what is they really want to accomplish. Once a company has done this, they can begin to factor out common sub business process like credit card process, user authentication or system notifications in to small components that can be built independent of each other and then reassembled to form new and dynamic services that are loosely coupled and agile in that they can change as a business grows.Another key pitfall of companies doing SOA is the fact that they let vendors drive their architecture. Why do companies do this? Vendors’ do not hold your company’s success as their top priority; in fact they hold their own success as their top priority by selling you as much stuff as you are willing to buy. In my experience companies tend to strive for the maximum amount of benefits with a minimal amount of cost. Does anyone else see any conflicts between this and the driving force behind vendors.Mike Kavis recommends in an article written in CIO.com that companies need to figure out what they need before they talk to a vendor or at least have some idea of what they need. It is important to thoroughly evaluate each vendor and watch them perform a live demo of their system so that you as the company fully understand what kind of product or service the vendor is actually offering. In addition, do research on each vendor that you are considering, check out blog posts, online reviews, and any information you can find on the vendor through various search engines.Finally he recommends companies to verify any recommendations supplied by a vendor. From personal experience this is very important. I can remember when the company I worked for purchased a $200,000 add-on to their phone system that never actually worked as it was intended. In fact, just after my departure from the company started the process of attempting to get their money back from the vendor. This potentially could have been avoided if the company had done the research before selecting this vendor to ensure that their product and vendor would live up to their claims. I know that some SOA vendor offer free training regarding SOA because they know that there are a lot of misconceptions about the topic. Superficially this is a great thing for companies to take part in especially if the company is starting to implement SOA architecture and are still unsure about some topics or are looking for some guidance regarding the topic. However beware that some companies will focus on their product line only regarding the training. As an example, InfoWorld.com claims that companies providing deep seminars disguised as training, focusing more about ESBs and SOA governance technology, and less on how to approach and solve the architectural issues of the attendees.In short, it is important to remember that we as software professionals are responsible for guiding a business’s technology sections should be well informed and fully understand any new concepts that may be considered for implementation. As I have demonstrated already a company that has a few web services does not mean that they are doing SOA.  Additionally, we must not let the new buzz word of the day drive our technology, but instead our technology decisions should be driven from research and proven experience. Finally, it is important to rely on vendors when necessary, however, always take what they say with a grain of salt while cross checking any claims that they may make because we have to live with the aftermath of a system after the vendors are gone.   References: Barry, D. K. (2011). Service-oriented architecture (SOA) definition. Retrieved 12 12, 2011, from Service-Architecture.com: http://www.service-architecture.com/web-services/articles/service-oriented_architecture_soa_definition.html Connell, B. (2003, 9). service-oriented architecture (SOA). Retrieved 12 12, 2011, from SearchSOA: http://searchsoa.techtarget.com/definition/service-oriented-architecture Erl, T. (2011, 12 12). Service-Oriented Architecture. Retrieved 12 12, 2011, from WhatIsSOA: http://www.whatissoa.com/p10.php InfoWorld. (2008, 6 1). Should you get your SOA knowledge from SOA vendors? . Retrieved 12 12, 2011, from InfoWorld.com: http://www.infoworld.com/d/architecture/should-you-get-your-soa-knowledge-soa-vendors-453 Kavis, M. (2008, 6 18). Top 10 Reasons Why People are Making SOA Fail. Retrieved 12 13, 2011, from CIO.com: http://www.cio.com/article/438413/Top_10_Reasons_Why_People_are_Making_SOA_Fail?page=5&taxonomyId=3016  

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• Why JSF Matters (to You)

  - by reza_rahman

        "Those who have knowledge, don’t predict. Those who predict, don’t have knowledge."                                                                                                    – Lao Tzu You may have noticed Thoughtworks recently crowned the likes AngularJS, etc imminent successors to server-side web frameworks. They apparently also deemed it necessary to single out JSF for righteous scorn. I have to say as I was reading the analysis I couldn't help but remember they also promptly jumped on the Ruby, Rails, Clojure, etc bandwagon a good few years ago seemingly similarly crowing these dynamic languages imminent successors to Java. I remember thinking then as I do now whether the folks at Thoughtworks are really that much smarter than me or if they are simply more prone to the Hipster buzz of the day. I'll let you make the final call on that one. I also noticed mention of "J2EE" in the context of JSF and had to wonder how up-to-date or knowledgeable the person writing the analysis actually was given that the term was basically retired almost a decade ago. There's one thing that I am absolutely sure about though - as a long time pretty happy user of JSF, I had no choice but to speak up on what I believe JSF offers. If you feel the same way, I would encourage you to support the team behind JSF whose hard work you may have benefited from over the years. True to his outspoken character PrimeFaces lead Cagatay Civici certainly did not mince words making the case for the JSF ecosystem - his excellent write-up is well worth a read. He specifically pointed out the practical problems in going whole hog with bare metal JavaScript, CSS, HTML for many development teams. I'll admit I had to smile when I read his closing sentence as well as the rather cheerful comments to the post from actual current JSF/PrimeFaces users that are apparently supposed to be on a gloomy death march. In a similar vein, OmniFaces developer Arjan Tijms did a great job pointing out the fact that despite the extremely competitive server-side Java Web UI space, JSF seems to manage to always consistently come out in either the number one or number two spot over many years and many data sources - do give his well-written message in the JAX-RS user forum a careful read. I don't think it's really reasonable to expect this to be the case for so many years if JSF was not at least a capable if not outstanding technology. If fact if you've ever wondered, Oracle itself is one of the largest JSF users on the planet. As Oracle's Shay Shmeltzer explains in a recent JSF Central interview, many of Oracle's strategic products such as ADF, ADF Mobile and Fusion Applications itself is built on JSF. There are well over 3,000 active developers working on these codebases. I don't think anyone can think of a more compelling reason to make sure that a technology is as effective as possible for practical development under real world conditions. Standing on the shoulders of the above giants, I feel like I can be pretty brief in making my own case for JSF: JSF is a powerful abstraction that brings the original Smalltalk MVC pattern to web development. This means cutting down boilerplate code to the bare minimum such that you really can think of just writing your view markup and then simply wire up some properties and event handlers on a POJO. The best way to see what this really means is to compare JSF code for a pretty small case to other approaches. You should then multiply the additional work for the typical enterprise project to try to understand what the productivity trade-offs are. This is reason alone for me to personally never take any other approach seriously as my primary web UI solution unless it can match the sheer productivity of JSF. Thanks to JSF's focus on components from the ground-up JSF has an extremely strong ecosystem that includes projects like PrimeFaces, RichFaces, OmniFaces, ICEFaces and of course ADF Faces/Mobile. These component libraries taken together constitute perhaps the largest widget set ever developed and optimized for a single web UI technology. To begin to grasp what this really means, just briefly browse the excellent PrimeFaces showcase and think about the fact that you can readily use the widgets on that showcase by just using some simple markup and knowing near to nothing about AJAX, JavaScript or CSS. JSF has the fair and legitimate advantage of being an open vendor neutral standard. This means that no single company, individual or insular clique controls JSF - openness, transparency, accountability, plurality, collaboration and inclusiveness is virtually guaranteed by the standards process itself. You have the option to choose between compatible implementations, escape any form of lock-in or even create your own compatible implementation! As you might gather from the quote at the top of the post, I am not a fan of crystal ball gazing and certainly don't want to engage in it myself. Who knows? However far-fetched it may seem maybe AngularJS is the only future we all have after all. If that is the case, so be it. Unlike what you might have been told, Java EE is about choice at heart and it can certainly work extremely well as a back-end for AngularJS. Likewise, you are also most certainly not limited to just JSF for working with Java EE - you have a rich set of choices like Struts 2, Vaadin, Errai, VRaptor 4, Wicket or perhaps even the new action-oriented web framework being considered for Java EE 8 based on the work in Jersey MVC... Please note that any views expressed here are my own only and certainly does not reflect the position of Oracle as a company.

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• How can I render multiple windows with DirectX 9 in C++?

  - by Friso1990

  I'm trying to render multiple windows, using DirectX 9 and swap chains, but even though I create 2 windows, I only see the first one that I've created. My RendererDX9 header is this: #include <d3d9.h> #include <Windows.h> #include <vector> #include "RAT_Renderer.h" namespace RAT_ENGINE { class RAT_RendererDX9 : public RAT_Renderer { public: RAT_RendererDX9(); ~RAT_RendererDX9(); void Init(RAT_WindowManager* argWMan); void CleanUp(); void ShowWin(); private: LPDIRECT3D9 renderInterface; // Used to create the D3DDevice LPDIRECT3DDEVICE9 renderDevice; // Our rendering device LPDIRECT3DSWAPCHAIN9* swapChain; // Swapchain to make multi-window rendering possible WNDCLASSEX wc; std::vector<HWND> hwindows; void Render(int argI); }; } And my .cpp file is this: #include "RAT_RendererDX9.h" static LRESULT CALLBACK MsgProc( HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam ); namespace RAT_ENGINE { RAT_RendererDX9::RAT_RendererDX9() : renderInterface(NULL), renderDevice(NULL) { } RAT_RendererDX9::~RAT_RendererDX9() { } void RAT_RendererDX9::Init(RAT_WindowManager* argWMan) { wMan = argWMan; // Register the window class WNDCLASSEX windowClass = { sizeof( WNDCLASSEX ), CS_CLASSDC, MsgProc, 0, 0, GetModuleHandle( NULL ), NULL, NULL, NULL, NULL, "foo", NULL }; wc = windowClass; RegisterClassEx( &wc ); for (int i = 0; i< wMan->getWindows().size(); ++i) { HWND hWnd = CreateWindow( "foo", argWMan->getWindow(i)->getName().c_str(), WS_OVERLAPPEDWINDOW, argWMan->getWindow(i)->getX(), argWMan->getWindow(i)->getY(), argWMan->getWindow(i)->getWidth(), argWMan->getWindow(i)->getHeight(), NULL, NULL, wc.hInstance, NULL ); hwindows.push_back(hWnd); } // Create the D3D object, which is needed to create the D3DDevice. renderInterface = (LPDIRECT3D9)Direct3DCreate9( D3D_SDK_VERSION ); // Set up the structure used to create the D3DDevice. Most parameters are // zeroed out. We set Windowed to TRUE, since we want to do D3D in a // window, and then set the SwapEffect to "discard", which is the most // efficient method of presenting the back buffer to the display. And // we request a back buffer format that matches the current desktop display // format. D3DPRESENT_PARAMETERS deviceConfig; ZeroMemory( &deviceConfig, sizeof( deviceConfig ) ); deviceConfig.Windowed = TRUE; deviceConfig.SwapEffect = D3DSWAPEFFECT_DISCARD; deviceConfig.BackBufferFormat = D3DFMT_UNKNOWN; deviceConfig.BackBufferHeight = 1024; deviceConfig.BackBufferWidth = 768; deviceConfig.EnableAutoDepthStencil = TRUE; deviceConfig.AutoDepthStencilFormat = D3DFMT_D16; // Create the Direct3D device. Here we are using the default adapter (most // systems only have one, unless they have multiple graphics hardware cards // installed) and requesting the HAL (which is saying we want the hardware // device rather than a software one). Software vertex processing is // specified since we know it will work on all cards. On cards that support // hardware vertex processing, though, we would see a big performance gain // by specifying hardware vertex processing. renderInterface->CreateDevice( D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, hwindows[0], D3DCREATE_SOFTWARE_VERTEXPROCESSING, &deviceConfig, &renderDevice ); this->swapChain = new LPDIRECT3DSWAPCHAIN9[wMan->getWindows().size()]; this->renderDevice->GetSwapChain(0, &swapChain[0]); for (int i = 0; i < wMan->getWindows().size(); ++i) { renderDevice->CreateAdditionalSwapChain(&deviceConfig, &swapChain[i]); } renderDevice->SetRenderState(D3DRS_CULLMODE, D3DCULL_CCW); // Set cullmode to counterclockwise culling to save resources renderDevice->SetRenderState(D3DRS_AMBIENT, 0xffffffff); // Turn on ambient lighting renderDevice->SetRenderState(D3DRS_ZENABLE, TRUE); // Turn on the zbuffer } void RAT_RendererDX9::CleanUp() { renderDevice->Release(); renderInterface->Release(); } void RAT_RendererDX9::Render(int argI) { // Clear the backbuffer to a blue color renderDevice->Clear( 0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB( 0, 0, 255 ), 1.0f, 0 ); LPDIRECT3DSURFACE9 backBuffer = NULL; // Set draw target this->swapChain[argI]->GetBackBuffer(0, D3DBACKBUFFER_TYPE_MONO, &backBuffer); this->renderDevice->SetRenderTarget(0, backBuffer); // Begin the scene renderDevice->BeginScene(); // End the scene renderDevice->EndScene(); swapChain[argI]->Present(NULL, NULL, hwindows[argI], NULL, 0); } void RAT_RendererDX9::ShowWin() { for (int i = 0; i < wMan->getWindows().size(); ++i) { ShowWindow( hwindows[i], SW_SHOWDEFAULT ); UpdateWindow( hwindows[i] ); // Enter the message loop MSG msg; while( GetMessage( &msg, NULL, 0, 0 ) ) { if (PeekMessage( &msg, NULL, 0U, 0U, PM_REMOVE ) ) { TranslateMessage( &msg ); DispatchMessage( &msg ); } else { Render(i); } } } } } LRESULT CALLBACK MsgProc( HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam ) { switch( msg ) { case WM_DESTROY: //CleanUp(); PostQuitMessage( 0 ); return 0; case WM_PAINT: //Render(); ValidateRect( hWnd, NULL ); return 0; } return DefWindowProc( hWnd, msg, wParam, lParam ); } I've made a sample function to make multiple windows: void RunSample1() { //Create the window manager. RAT_ENGINE::RAT_WindowManager* wMan = new RAT_ENGINE::RAT_WindowManager(); //Create the render manager. RAT_ENGINE::RAT_RenderManager* rMan = new RAT_ENGINE::RAT_RenderManager(); //Create a window. //This is currently needed to initialize the render manager and create a renderer. wMan->CreateRATWindow("Sample 1 - 1", 10, 20, 640, 480); wMan->CreateRATWindow("Sample 1 - 2", 150, 100, 480, 640); //Initialize the render manager. rMan->Init(wMan); //Show the window. rMan->getRenderer()->ShowWin(); } How do I get the multiple windows to work?

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• 11gR2 ???:Oracle Cluster Health Monitor(CHM)??

  - by JaneZhang(???)

     Cluster Health Monitor(????CHM)???Oracle?????,?????????????(CPU????SWAP????I/O?????)??????CHM??????????   ??????????????????????Hang?????(Eviction)????????????????,??????CHM????????????????????,????????????? CHM???????????:    11.2.0.2 ?????? Oracle Grid Infrastructure for Linux (???Linux Itanium) ?Solaris (Sparc 64 ? x86-64)    11.2.0.3 ????? Oracle Grid Infrastructure for AIX ? Windows (???Windows Itanium)?    ????,???????????CHM?????(ora.crf)???:    $ crsctl stat res -t -init    --------------------------------------------------------------------------------    NAME           TARGET  STATE        SERVER                   STATE_DETAILS       Cluster Resources ora.crf        ONLINE  ONLINE       rac1 CHM????????:    1). System Monitor Service(osysmond):?????????????,osysmond????????????????cluster logger service,???????????????????CHM?????      $ ps -ef|grep osysmond       root      7984     1  0 Jun05 ?        01:16:14 /u01/app/11.2.0/grid/bin/osysmond.bin    2). Cluster Logger Service(ologgerd):???????,ologgerd ???????(master),???????(standby)??ologgerd???????????????,??????????     ???:     $ ps -ef|grep ologgerd       root      8257     1  0 Jun05 ?        00:38:26 /u01/app/11.2.0/grid/bin/ologgerd -M -d       /u01/app/11.2.0/grid/crf/db/rac2     ???:      $ ps -ef|grep ologgerd       root      8353     1  0 Jun05 ?        00:18:47 /u01/app/11.2.0/grid/bin/ologgerd -m rac2 -r -d /u01/app/11.2.0/grid/crf/db/rac1 CHM Repository:?????????,?????,????Grid Infrastructure home ? ,??1 GB ?????,???????????0.5GB???? ?????OCLUMON??????????????????(??????3????)? ??????????????:     $ oclumon manage -get reppath       CHM Repository Path = /u01/app/11.2.0/grid/crf/db/rac2       Done     $ oclumon manage -get repsize       CHM Repository Size = 68082 <====????       Done     ????:     $ oclumon manage -repos reploc /shared/oracle/chm      ????:     $ oclumon manage -repos resize 68083 <==?3600(??) ? 259200(3?)??      rac1 --> retention check successful      New retention is 68083 and will use 1073750609 bytes of disk space      CRS-9115-Cluster Health Monitor repository size change completed on all nodes.      Done ??CHM???????????:     1. ?????Grid_home/bin/diagcollection.pl:         1). ??,??cluster logger service????:         $ oclumon manage -get master         Master = rac2         2).?root??????rac2???????:         # <Grid_home>/bin/diagcollection.pl -collect -chmos -incidenttime inc_time -incidentduration duration         inc_time?????????????,???MM/DD/YYYY24HH:MM:SS, duration??????????????????         ??:# diagcollection.pl -collect -crshome /u01/app/11.2.0/grid -chmoshome  /u01/app/11.2.0/grid -chmos -incidenttime 06/15/201215:30:00 -incidentduration 00:05       3).????????,CHM?????????chmosData_rac2_20120615_1537.tar.gz?    2. ??????CHM?????????oclumon:        $oclumon dumpnodeview [[-allnodes] | [-n node1 node2] [-last "duration"] | [-s "time_stamp" -e "time_stamp"] [-v] [-warning]] [-h]        -s??????,-e??????        $ oclumon dumpnodeview -allnodes -v -s "2012-06-15 07:40:00" -e "2012-06-15 07:57:00" > /tmp/chm1.txt       $ oclumon dumpnodeview -n node1 node2 node3 -last "12:00:00" >/tmp/chm1.txt       $ oclumon dumpnodeview -allnodes -last "00:15:00" >/tmp/chm1.txt ???/tmp/chm1.txt??????:----------------------------------------Node: rac1 Clock: '06-15-12 07.40.01' SerialNo:168880----------------------------------------SYSTEM:#cpus: 1 cpu: 17.96 cpuq: 5 physmemfree: 32240 physmemtotal: 2065856 mcache: 1064024 swapfree: 3988376 swaptotal: 4192956 ior: 57 iow: 59 ios: 10 swpin: 0 swpout: 0 pgin: 57 pgout: 59 netr: 65.767 netw: 34.871 procs: 183 rtprocs: 10 #fds: 4902 #sysfdlimit: 6815744 #disks: 4 #nics: 3  nicErrors: 0TOP CONSUMERS:topcpu: 'mrtg(32385) 64.70' topprivmem: 'ologgerd(8353) 84068' topshm: 'oracle(8760) 329452' topfd: 'ohasd.bin(6627) 720' topthread: 'crsd.bin(8235) 44'PROCESSES:name: 'mrtg' pid: 32385 #procfdlimit: 65536 cpuusage: 64.70 privmem: 1160 shm: 1584 #fd: 5 #threads: 1 priority: 20 nice: 0name: 'oracle' pid: 32381 #procfdlimit: 65536 cpuusage: 0.29 privmem: 1456 shm: 12444 #fd: 32 #threads: 1 priority: 15 nice: 0...name: 'oracle' pid: 8756 #procfdlimit: 65536 cpuusage: 0.0 privmem: 2892 shm: 24356 #fd: 47 #threads: 1 priority: 16 nice: 0----------------------------------------Node: rac2 Clock: '06-15-12 07.40.02' SerialNo:168878----------------------------------------SYSTEM:#cpus: 1 cpu: 40.72 cpuq: 8 physmemfree: 34072 physmemtotal: 2065856 mcache: 1005636 swapfree: 3991808 swaptotal: 4192956 ior: 54 iow: 104 ios: 11 swpin: 0 swpout: 0 pgin: 54 pgout: 104 netr: 77.817 netw: 33.008 procs: 178 rtprocs: 10 #fds: 4948 #sysfdlimit: 6815744 #disks: 4 #nics: 4  nicErrors: 0TOP CONSUMERS:topcpu: 'orarootagent.bi(8490) 1.59' topprivmem: 'ologgerd(8257) 83108' topshm: 'oracle(8873) 324868' topfd: 'ohasd.bin(6744) 720' topthread: 'crsd.bin(8362) 47'PROCESSES:name: 'oracle' pid: 9040 #procfdlimit: 65536 cpuusage: 0.19 privmem: 6040 shm: 121712 #fd: 33 #threads: 1 priority: 16 nice: 0...  ??CHM?????,???Oracle????:  http://docs.oracle.com/cd/E11882_01/rac.112/e16794/troubleshoot.htm#CWADD92242  Oracle® Clusterware Administration and Deployment Guide  11g Release 2 (11.2)  Part Number E16794-17  ?? My Oracle Support??:  Cluster Health Monitor (CHM) FAQ (Doc ID 1328466.1)

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• User Input That Involves A ' ' Causes A Substring Out Of Range Error

  - by Greenhouse Gases

  Hi Stackoverflow people. You have already helped me quite a bit but near the end of writing this program I have somewhat of a bug. You see in order to read in city names with a space in from a text file I use a '/' that is then replaced by the program for a ' ' (and when the serializer runs the opposite happens for next time the program is run). The problem is when a user inputs a name too add, search for, or delete that contains a space, for instance 'New York' I get a Debug Assertion Error with a substring out of range expression. I have a feeling it's to do with my correctCase function, or setElementsNull that looks at the string until it experiences a null element in the array, however ' ' is not null so I'm not sure how to fix this and I'm going a bit insane. Any help would be much appreciated. Here is my code: // U08221.cpp : main project file. #include "stdafx.h" #include <_iostream> #include <_string> #include <_fstream> #include <_cmath> using namespace std; class locationNode { public: string nodeCityName; double nodeLati; double nodeLongi; locationNode* Next; locationNode(string nameOf, double lat, double lon) { this->nodeCityName = nameOf; this->nodeLati = lat; this->nodeLongi = lon; this->Next = NULL; } locationNode() // NULL constructor { } void swapProps(locationNode *node2) { locationNode place; place.nodeCityName = this->nodeCityName; place.nodeLati = this->nodeLati; place.nodeLongi = this->nodeLongi; this->nodeCityName = node2->nodeCityName; this->nodeLati = node2->nodeLati; this->nodeLongi = node2->nodeLongi; node2->nodeCityName = place.nodeCityName; node2->nodeLati = place.nodeLati; node2->nodeLongi = place.nodeLongi; } void modify(string name) { this->nodeCityName = name; } void modify(double latlon, int mod) { switch(mod) { case 2: this->nodeLati = latlon; break; case 3: this->nodeLongi = latlon; break; } } void correctCase() // Correct upper and lower case letters of input { int MAX_SIZE = 35; int firstLetVal = this->nodeCityName[0], letVal; int n = 1; // variable for name index from second letter onwards if((this->nodeCityName[0] >90) && (this->nodeCityName[0] < 123)) // First letter is lower case { firstLetVal = firstLetVal - 32; // Capitalise first letter this->nodeCityName[0] = firstLetVal; } while(this->nodeCityName[n] != NULL) { if((this->nodeCityName[n] >= 65) && (this->nodeCityName[n] <= 90)) { if(this->nodeCityName[n - 1] != 32) { letVal = this->nodeCityName[n] + 32; this->nodeCityName[n] = letVal; } } n++; } } }; Here is the main part of the program: // U08221.cpp : main project file. #include "stdafx.h" #include "Locations2.h" #include <_iostream> #include <_string> #include <_fstream> #include <_cmath> using namespace std; #define pi 3.14159265358979323846264338327950288 #define radius 6371 #define gig 1073741824 //size of a gigabyte in bytes int n = 0,x, locationCount = 0, MAX_SIZE = 35 , g = 0, i = 0, modKey = 0, xx; string cityNameInput, alter; char targetCity[35], skipKey = ' '; double lat1, lon1, lat2, lon2, dist, dummy, modVal, result; bool acceptedInput = false, match = false, nodeExists = false;// note: addLocation(), set to true to enable user input as opposed to txt file locationNode *temp, *temp2, *example, *seek, *bridge, *start_ptr = NULL; class Menu { int junction; public: /* Convert decimal degrees to radians */ public: void setElementsNull(char cityParam[]) { int y=0; while(cityParam[y] != NULL) { y++; } while(y < MAX_SIZE) { cityParam[y] = NULL; y++; } } void correctCase(string name) // Correct upper and lower case letters of input { int MAX_SIZE = 35; int firstLetVal = name[0], letVal; int n = 1; // variable for name index from second letter onwards if((name[0] >90) && (name[0] < 123)) // First letter is lower case { firstLetVal = firstLetVal - 32; // Capitalise first letter name[0] = firstLetVal; } while(name[n] != NULL) { if((name[n] >= 65) && (name[n] <= 90)) { letVal = name[n] + 32; name[n] = letVal; } n++; } for(n = 0; targetCity[n] != NULL; n++) { targetCity[n] = name[n]; } } bool nodeExistTest(char targetCity[]) // see if entry is present in the database { match = false; seek = start_ptr; int letters = 0, letters2 = 0, x = 0, y = 0; while(targetCity[y] != NULL) { letters2++; y++; } while(x <= locationCount) // locationCount is number of entries currently in list { y=0, letters = 0; while(seek->nodeCityName[y] != NULL) // count letters in the current name { letters++; y++; } if(letters == letters2) // same amount of letters in the name { y = 0; while(y <= letters) // compare each letter against one another { if(targetCity[y] == seek->nodeCityName[y]) { match = true; y++; } else { match = false; y = letters + 1; // no match, terminate comparison } } } if(match) { x = locationCount + 1; //found match so terminate loop } else{ if(seek->Next != NULL) { bridge = seek; seek = seek->Next; x++; } else { x = locationCount + 1; // end of list so terminate loop } } } return match; } double deg2rad(double deg) { return (deg * pi / 180); } /* Convert radians to decimal degrees */ double rad2deg(double rad) { return (rad * 180 / pi); } /* Do the calculation */ double distance(double lat1, double lon1, double lat2, double lon2, double dist) { dist = sin(deg2rad(lat1)) * sin(deg2rad(lat2)) + cos(deg2rad(lat1)) * cos(deg2rad(lat2)) * cos(deg2rad(lon1 - lon2)); dist = acos(dist); dist = rad2deg(dist); dist = (radius * pi * dist) / 180; return dist; } void serialise() { // Serialize to format that can be written to text file fstream outfile; outfile.open("locations.txt",ios::out); temp = start_ptr; do { for(xx = 0; temp->nodeCityName[xx] != NULL; xx++) { if(temp->nodeCityName[xx] == 32) { temp->nodeCityName[xx] = 47; } } outfile << endl << temp->nodeCityName<< " "; outfile<<temp->nodeLati<< " "; outfile<<temp->nodeLongi; temp = temp->Next; }while(temp != NULL); outfile.close(); } void sortList() // do this { int changes = 1; locationNode *node1, *node2; while(changes > 0) // while changes are still being made to the list execute { node1 = start_ptr; node2 = node1->Next; changes = 0; do { xx = 1; if(node1->nodeCityName[0] > node2->nodeCityName[0]) //compare first letter of name with next in list { node1->swapProps(node2); // should come after the next in the list changes++; } else if(node1->nodeCityName[0] == node2->nodeCityName[0]) // if same first letter { while(node1->nodeCityName[xx] == node2->nodeCityName[xx]) // check next letter of name { if((node1->nodeCityName[xx + 1] != NULL) && (node2->nodeCityName[xx + 1] != NULL)) // check next letter until not the same { xx++; } else break; } if(node1->nodeCityName[xx] > node2->nodeCityName[xx]) { node1->swapProps(node2); // should come after the next in the list changes++; } } node1 = node2; node2 = node2->Next; // move to next pair in list } while(node2 != NULL); } } void initialise() { cout << "Populating List..."; ifstream inputFile; inputFile.open ("locations.txt", ios::in); char inputName[35] = " "; double inputLati = 0, inputLongi = 0; //temp = new locationNode(inputName, inputLati, inputLongi); do { inputFile.get(inputName, 35, ' '); inputFile >> inputLati; inputFile >> inputLongi; if(inputName[0] == 10 || 13) //remove linefeed from input { for(int i = 0; inputName[i] != NULL; i++) { inputName[i] = inputName[i + 1]; } } for(xx = 0; inputName[xx] != NULL; xx++) { if(inputName[xx] == 47) // if it is a '/' { inputName[xx] = 32; // replace it for a space } } temp = new locationNode(inputName, inputLati, inputLongi); if(start_ptr == NULL){ // if list is currently empty, start_ptr will point to this node start_ptr = temp; } else { temp2 = start_ptr; // We know this is not NULL - list not empty! while (temp2->Next != NULL) { temp2 = temp2->Next; // Move to next link in chain until reach end of list } temp2->Next = temp; } ++locationCount; // increment counter for number of records in list } while(!inputFile.eof()); cout << "Successful!" << endl << "List contains: " << locationCount << " entries" << endl; inputFile.close(); cout << endl << "*******************************************************************" << endl << "DISTANCE CALCULATOR v2.0\tAuthors: Darius Hodaei, Joe Clifton" << endl; } void menuInput() { char menuChoice = ' '; while(menuChoice != 'Q') { // Menu if(skipKey != 'X') // This is set by case 'S' below if a searched term does not exist but wants to be added { cout << endl << "*******************************************************************" << endl; cout << "Please enter a choice for the menu..." << endl << endl; cout << "(P) To print out the list" << endl << "(O) To order the list alphabetically" << endl << "(A) To add a location" << endl << "(D) To delete a record" << endl << "(C) To calculate distance between two points" << endl << "(S) To search for a location in the list" << endl << "(M) To check memory usage" << endl << "(U) To update a record" << endl << "(Q) To quit" << endl; cout << endl << "*******************************************************************" << endl; cin >> menuChoice; if(menuChoice >= 97) { menuChoice = menuChoice - 32; // Turn the lower case letter into an upper case letter } } skipKey = ' '; //Reset skipKey so that it does not skip the menu switch(menuChoice) { case 'P': temp = start_ptr; // set temp to the start of the list do { if (temp == NULL) { cout << "You have reached the end of the database" << endl; } else { // Display details for what temp points to at that stage cout << "Location : " << temp->nodeCityName << endl; cout << "Latitude : " << temp->nodeLati << endl; cout << "Longitude : " << temp->nodeLongi << endl; cout << endl; // Move on to next locationNode if one exists temp = temp->Next; } } while (temp != NULL); break; case 'O': { sortList(); // pass by reference??? cout << "List reordered alphabetically" << endl; } break; case 'A': char cityName[35]; double lati, longi; cout << endl << "Enter the name of the location: "; cin >> cityName; for(xx = 0; cityName[xx] != NULL; xx++) { if(cityName[xx] == 47) // if it is a '/' { cityName[xx] = 32; // replace it for a space } } if(!nodeExistTest(cityName)) { cout << endl << "Please enter the latitude value for this location: "; cin >> lati; cout << endl << "Please enter the longitude value for this location: "; cin >> longi; cout << endl; temp = new locationNode(cityName, lati, longi); temp->correctCase(); //start_ptr allignment if(start_ptr == NULL){ // if list is currently empty, start_ptr will point to this node start_ptr = temp; } else { temp2 = start_ptr; // We know this is not NULL - list not empty! while (temp2->Next != NULL) { temp2 = temp2->Next; // Move to next link in chain until reach end of list } temp2->Next = temp; } ++locationCount; // increment counter for number of records in list cout << "Location sucessfully added to the database! There are " << locationCount << " location(s) stored" << endl; } else { cout << "Node is already present in the list and so cannot be added again" << endl; } break; case 'D': { junction = 0; locationNode *place; cout << "Enter the name of the city you wish to remove" << endl; cin >> targetCity; setElementsNull(targetCity); correctCase(targetCity); for(xx = 0; targetCity[xx] != NULL; xx++) { if(targetCity[xx] == 47) { targetCity[xx] = 32; } } if(nodeExistTest(targetCity)) //if this node does exist { if(seek == start_ptr) // if it is the first in the list { junction = 1; } if(seek->Next == NULL) // if it is last in the list { junction = 2; } switch(junction) // will alter list accordingly dependant on where the searched for link is { case 1: start_ptr = start_ptr->Next; delete seek; --locationCount; break; case 2: place = seek; seek = bridge; seek->Next = NULL; delete place; --locationCount; break; default: bridge->Next = seek->Next; delete seek; --locationCount; break; } cout << endl << "Link deleted. There are now " << locationCount << " locations." << endl; } else { cout << "That entry does not currently exist" << endl << endl << endl; } } break; case 'C': { char city1[35], city2[35]; cout << "Enter the first city name" << endl; cin >> city1; setElementsNull(city1); correctCase(targetCity); if(nodeExistTest(city1)) { lat1 = seek->nodeLati; lon1 = seek->nodeLongi; cout << "Lati = " << seek->nodeLati << endl << "Longi = " << seek->nodeLongi << endl << endl; } cout << "Enter the second city name" << endl; cin >> city2; setElementsNull(city2); correctCase(targetCity); if(nodeExistTest(city2)) { lat2 = seek->nodeLati; lon2 = seek->nodeLongi; cout << "Lati = " << seek->nodeLati << endl << "Longi = " << seek->nodeLongi << endl << endl; } result = distance (lat1, lon1, lat2, lon2, dist); cout << "The distance between these two locations is " << result << " kilometres." << endl; } break; case 'S': { char choice; cout << "Enter search term..." << endl; cin >> targetCity; setElementsNull(targetCity); correctCase(targetCity); if(nodeExistTest(targetCity)) { cout << "Latitude: " << seek->nodeLati << endl << "Longitude: " << seek->nodeLongi << endl; } else { cout << "Sorry, that city is not currently present in the list." << endl << "Would you like to add this city now Y/N?" << endl; cin >> choice; /*while(choice != ('Y' || 'N')) { cout << "Please enter a valid choice..." << endl; cin >> choice; }*/ switch(choice) { case 'Y': skipKey = 'X'; menuChoice = 'A'; break; case 'N': break; default : cout << "Invalid choice" << endl; break; } } break; } case 'M': { cout << "Locations currently stored: " << locationCount << endl << "Memory used for this: " << (sizeof(start_ptr) * locationCount) << " bytes" << endl << endl << "You can store " << ((gig - (sizeof(start_ptr) * locationCount)) / sizeof(start_ptr)) << " more locations" << endl ; break; } case 'U': { cout << "Enter the name of the Location you would like to update: "; cin >> targetCity; setElementsNull(targetCity); correctCase(targetCity); if(nodeExistTest(targetCity)) { cout << "Select (1) to alter City Name, (2) to alter Longitude, (3) to alter Latitude" << endl; cin >> modKey; switch(modKey) { case 1: cout << "Enter the new name: "; cin >> alter; cout << endl; seek->modify(alter); break; case 2: cout << "Enter the new latitude: "; cin >> modVal; cout << endl; seek->modify(modVal, modKey); break; case 3: cout << "Enter the new longitude: "; cin >> modVal; cout << endl; seek->modify(modVal, modKey); break; default: break; } } else cout << "Location not found" << endl; break; } } } } }; int main(array<System::String ^> ^args) { Menu mm; //mm.initialise(); mm.menuInput(); mm.serialise(); }

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• debian lenny xen bridge networking problem

  - by Sasha

  DomU isn't talking to the world, but it talks to Dom0. Here are the tests that I made: Dom0 (external networking is working): ping 188.40.96.238 #Which is Domu's ip PING 188.40.96.238 (188.40.96.238) 56(84) bytes of data. 64 bytes from 188.40.96.238: icmp_seq=1 ttl=64 time=0.092 ms DomU: ping 188.40.96.215 #Which is Dom0's ip PING 188.40.96.215 (188.40.96.215) 56(84) bytes of data. 64 bytes from 188.40.96.215: icmp_seq=1 ttl=64 time=0.045 ms ping 188.40.96.193 #Which is the gateway - fail PING 188.40.96.193 (188.40.96.193) 56(84) bytes of data. ^C --- 188.40.96.193 ping statistics --- 2 packets transmitted, 0 received, 100% packet loss, time 1013ms The system is debian lenny with a normal setup. Here is my configs: uname -a Linux green0 2.6.26-2-xen-686 #1 SMP Wed Aug 19 08:47:57 UTC 2009 i686 GNU/Linux cat /etc/xen/green1.cfg |grep -v '#' kernel = '/boot/vmlinuz-2.6.26-2-xen-686' ramdisk = '/boot/initrd.img-2.6.26-2-xen-686' memory = '2000' root = '/dev/xvda2 ro' disk = [ 'file:/home/xen/domains/green1/swap.img,xvda1,w', 'file:/home/xen/domains/green1/disk.img,xvda2,w', ] name = 'green1' vif = [ 'ip=188.40.96.238,mac=00:16:3E:1F:C4:CC' ] on_poweroff = 'destroy' on_reboot = 'restart' on_crash = 'restart' ifconfig eth0 Link encap:Ethernet HWaddr 00:24:21:ef:2f:86 inet addr:188.40.96.215 Bcast:188.40.96.255 Mask:255.255.255.192 inet6 addr: fe80::224:21ff:feef:2f86/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:3296 errors:0 dropped:0 overruns:0 frame:0 TX packets:2204 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:262717 (256.5 KiB) TX bytes:330465 (322.7 KiB) lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) peth0 Link encap:Ethernet HWaddr 00:24:21:ef:2f:86 inet6 addr: fe80::224:21ff:feef:2f86/64 Scope:Link UP BROADCAST RUNNING PROMISC MULTICAST MTU:1500 Metric:1 RX packets:3407 errors:0 dropped:657431448 overruns:0 frame:0 TX packets:2291 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:319941 (312.4 KiB) TX bytes:338423 (330.4 KiB) Interrupt:16 Base address:0x8000 vif2.0 Link encap:Ethernet HWaddr fe:ff:ff:ff:ff:ff inet6 addr: fe80::fcff:ffff:feff:ffff/64 Scope:Link UP BROADCAST RUNNING PROMISC MULTICAST MTU:1500 Metric:1 RX packets:27 errors:0 dropped:0 overruns:0 frame:0 TX packets:151 errors:0 dropped:33 overruns:0 carrier:0 collisions:0 txqueuelen:32 RX bytes:1164 (1.1 KiB) TX bytes:20974 (20.4 KiB) ip a s 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: peth0: <BROADCAST,MULTICAST,PROMISC,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN qlen 1000 link/ether 00:24:21:ef:2f:86 brd ff:ff:ff:ff:ff:ff inet6 fe80::224:21ff:feef:2f86/64 scope link valid_lft forever preferred_lft forever 4: vif0.0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN link/ether fe:ff:ff:ff:ff:ff brd ff:ff:ff:ff:ff:ff 5: veth0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN link/ether 00:00:00:00:00:00 brd ff:ff:ff:ff:ff:ff 6: vif0.1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN link/ether fe:ff:ff:ff:ff:ff brd ff:ff:ff:ff:ff:ff 7: veth1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN link/ether 00:00:00:00:00:00 brd ff:ff:ff:ff:ff:ff 8: vif0.2: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN link/ether fe:ff:ff:ff:ff:ff brd ff:ff:ff:ff:ff:ff 9: veth2: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN link/ether 00:00:00:00:00:00 brd ff:ff:ff:ff:ff:ff 10: vif0.3: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN link/ether fe:ff:ff:ff:ff:ff brd ff:ff:ff:ff:ff:ff 11: veth3: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN link/ether 00:00:00:00:00:00 brd ff:ff:ff:ff:ff:ff 12: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN link/ether 00:24:21:ef:2f:86 brd ff:ff:ff:ff:ff:ff inet 188.40.96.215/26 brd 188.40.96.255 scope global eth0 inet6 fe80::224:21ff:feef:2f86/64 scope link valid_lft forever preferred_lft forever 14: vif2.0: <BROADCAST,MULTICAST,PROMISC,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN qlen 32 link/ether fe:ff:ff:ff:ff:ff brd ff:ff:ff:ff:ff:ff inet6 fe80::fcff:ffff:feff:ffff/64 scope link valid_lft forever preferred_lft forever brctl show bridge name bridge id STP enabled interfaces eth0 8000.002421ef2f86 no peth0 vif2.0 ip r l Dom0: 188.40.96.192/26 dev eth0 proto kernel scope link src 188.40.96.215 default via 188.40.96.193 dev eth0 DomU: 188.40.96.192/26 dev eth0 proto kernel scope link src 188.40.96.238 default via 188.40.96.193 dev eth0

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• PHP pages working slow from time to time

  - by user1038179

  I have VPS with limit of 2GB of ram and 8 CPU cores. I have 5 sites on that VPS (one of them is just for testing, no visitors exept me). All 5 sites are image galleries, like wallpaper sites. Last week I noticed problem on one site (main domain, used for name servers, and also with most traffic, visitors). That site has two image galleries, one is old static html gallery made few years ago and another, main, is powered by ZENPhoto CMS. Also I have that same gallery CMS on another two sites on that same VPS (on one running site and on one just for testing site). On other two sites I have diferent PHP driven gallery. Problem is that after some time (it vary from 10 minutes to few hours after apache restart), loading of pages on main site becomes very slow, or I get 503 Service Temporarily Unavailable error. So pages becomes unavailable. But just that part with new CMS gallery, old part of site with static html pages are working fast and just fine. Also other two sites with same CMS gallery and other two with different PHP driven gallery are working fine and fast at the same time. I thought it must be something with CMS on that main site, because other sites are working nice. Then I tryed to open contact and guest book pages on that main site which are outside of that CMS but also PHP pages, and they do not load too, but that same contact php scipts are working on other sites at the same time. So, when site starts to hangs, ONLY PHP generated content is not working, like I said other static pages are working. And, ONLY on that one main site I have problems. Then I need to restart Apache, after restart everything is vorking nice and fast, for some time, than again, just PHP pages on main site are becomming slower. If I do not restart apache that slowness take some time (several minutes, hours, depending ot traffic) and during that time PHP diven content is loading very slow or unavailable on that site. After sime time, on moments everything start to work and is fast again for some time, and again. In hours with more traffic PHP content is loading slowly or it is unavailable, in hours with less traffic it is sometimes fast and sometimes little bit slower than usually. And ones again, only on that main site, and only PHP driven pages, static pages are working fast even in most traffic hours also other sites with even same CMS are working fast. Currently I have about 7000 unique visitors on that site but site worked nice even with 11500 visitors per day. And about 17000 in total visitors on VPS, all sites ( about 3 pages per unique visitor). When site start to slow down sometimes in apache status I can see something like this: mod_fcgid status: Total FastCGI processes: 37 Process: php5 (/usr/local/cpanel/cgi-sys/php5)Pid Active Idle Accesses State 11300 39 28 7 Working 11274 47 28 7 Working 11296 40 29 3 Working 11283 45 30 3 Working 11304 36 31 1 Working 11282 46 32 3 Working 11292 42 33 1 Working 11289 44 34 1 Working 11305 35 35 0 Working 11273 48 36 2 Working 11280 47 39 1 Working 10125 133 40 12 Exiting(communication error) 11294 41 41 1 Exiting(communication error) 11277 47 42 2 Exiting(communication error) 11291 43 43 1 Exiting(communication error) 10187 108 43 10 Exiting(communication error) 10209 95 44 7 Exiting(communication error) 10171 113 44 5 Exiting(communication error) 11275 47 47 1 Exiting(communication error) 10144 125 48 8 Exiting(communication error) 10086 149 48 20 Exiting(communication error) 10212 94 49 5 Exiting(communication error) 10158 118 49 5 Exiting(communication error) 10169 114 50 4 Exiting(communication error) 10105 141 50 16 Exiting(communication error) 10094 146 50 15 Exiting(communication error) 10115 139 51 17 Exiting(communication error) 10213 93 51 9 Exiting(communication error) 10197 103 51 7 Exiting(communication error) Process: php5 (/usr/local/cpanel/cgi-sys/php5)Pid Active Idle Accesses State 7983 1079 2 149 Ready 7979 1079 11 151 Ready Process: php5 (/usr/local/cpanel/cgi-sys/php5)Pid Active Idle Accesses State 7990 1066 0 57 Ready 8001 1031 64 35 Ready 7999 1032 94 29 Ready 8000 1031 91 36 Ready 8002 1029 34 52 Ready Process: php5 (/usr/local/cpanel/cgi-sys/php5)Pid Active Idle Accesses State 7991 1064 29 115 Ready When it is working nicly there is no lines with "Exiting(communication error)" Active and Idle are time active and time since last request, in seconds. Here are system info. Sysem info: Total processors: 8 Processor #1 Vendor GenuineIntel Name Intel(R) Xeon(R) CPU E5440 @ 2.83GHz Speed 88.320 MHz Cache 6144 KB All other seven are the same. System Information Linux vps.nnnnnnnnnnnnnnnnn.nnn 2.6.18-028stab099.3 #1 SMP Wed Mar 7 15:20:22 MSK 2012 x86_64 x86_64 x86_64 GNU/Linux Current Memory Usage total used free shared buffers cached Mem: 8388608 882164 7506444 0 0 0 -/+ buffers/cache: 882164 7506444 Swap: 0 0 0 Total: 8388608 882164 7506444 Current Disk Usage Filesystem Size Used Avail Use% Mounted on /dev/vzfs 100G 34G 67G 34% / none System Details: Running on: Apache/2.2.22 System info: (Unix) mod_ssl/2.2.22 OpenSSL/0.9.8e-fips-rhel5 DAV/2 mod_auth_passthrough/2.1 mod_bwlimited/1.4 FrontPage/5.0.2.2635 mod_fcgid/2.3.6 Powered by: PHP/5.3.10 Current Configuration Default PHP Version (.php files) 5 PHP 5 Handler fcgi PHP 4 Handler suphp Apache suEXEC on Apache Ruid2 off PHP 4 Handler suphp Apache suEXEC on Apache Configuration The following settings have been saved: fileetag: All keepalive: On keepalivetimeout: 3 maxclients: 150 maxkeepaliverequests: 10 maxrequestsperchild: 10000 maxspareservers: 10 minspareservers: 5 root_options: ExecCGI, FollowSymLinks, Includes, IncludesNOEXEC, Indexes, MultiViews, SymLinksIfOwnerMatch serverlimit: 256 serversignature: Off servertokens: Full sslciphersuite: ALL:!ADH:RC4+RSA:+HIGH:+MEDIUM:-LOW:-SSLv2:-EXP:!kEDH startservers: 5 timeout: 30 I hope, I explained my problem nicely. Any help would be nice.

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