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  • How to Never Use iTunes With Your iPhone, iPad, or iPod Touch

    - by Chris Hoffman
    iTunes isn’t an amazing program on Windows. There was a time when Apple device users had to plug their devices into their PCs or Macs and use iTunes for device activation, updates, and syncing, but iTunes is no longer necessary. Apple still allows you to use iTunes for these things, but you don’t have to. Your iOS device can function independently from iTunes, so you should never be forced to plug it into a PC or Mac. Device Activation When the iPad first came out, it was touted as a device that could replace full PCs and Macs for people who only needed to perform light computing tasks. Yet, to set up a new iPad, users had to plug it into a PC or Mac running iTunes and use iTunes to activate the device. This is no longer necessary. With new iPads, iPhones, and iPod Touches, you can simply go through the setup process after turning on your new device without ever having to plug it into iTunes. Just connect to a Wi-Fi or cellular data network and log in with your Apple ID when prompted. You’ll still see an option that allows you to activate the device via iTunes, but this should only be necessary if you don’t have a wireless Internet connection available for your device. Operating System Updates You no longer have to use Apple’s iTunes software to update to a new version of Apple’s iOS operating system, either. Just open the Settings app on your device, select the General category, and tap Software Update. You’ll be able to update right from your device without ever opening iTunes. Purchased iTunes Media Apple allows you to easily access content you’ve purchased from the iTunes Store on any device. You don’t have to connect your device to your computer and sync via iTunes. For example, you can purchase a movie from the iTunes Store. Then, without any syncing, you can open the iTunes Store app on any of your iOS devices, tap the Purchased section, and see stuff you’ve downloaded. You can download the content right from the store to your device. This also works for apps — apps you purchase from the App Store can be accessed in the Purchased section on the App Store on your device later. You don’t have to sync apps from iTunes to your device, although iTunes still allows you to. You can even set up automatic downloads from the iTunes & App Store settings screen. This would allow you to purchase content on one device and have it automatically download to your other devices without any hassle. Music Apple allows you to re-download purchased music from the iTunes Store in the same way. However, there’s a good chance you have your own music you didn’t purchase from iTunes. Maybe you spent time ripping it all from your old CDs and you’ve been syncing it to your devices via iTunes ever since. Apple’s solution for this is named iTunes Match. This feature isn’t free, but it’s not a bad deal at all. For $25 per year, Apple allows you to upload all your music to your iCloud account. You can then access all your music from any iPhone, IPad, or iPod Touch. You can stream all your music — perfect if you have a huge library and little storage on your device — and choose which songs you want to download to your device for offline use. When you add additional music to your computer, iTunes will notice it and upload it using iTunes Match, making it available for streaming and downloading directly from your iOS devices without any syncing. This feature is named iTunes Match because it doesn’t just upload music — if Apple already has a song you upload, it will “match” your song with Apple’s copy. This means you may get higher-quality versions of your songs if you ripped them from CD at a lower bitrate. Podcasts You don’t have to use iTunes to subscribe to podcasts and sync them to your devices. Even if you have a lowly iPod Touch, you can install APple’s Podcasts app from the app store. Use it to subscribe to podcasts and configure them to automatically download directly to your device. You can use other podcast apps for this, too. Backups You can continue backing up your device’s data through iTunes, generating local backups that are stored on your computer. However, new iOS devices are configured to automatically back up their data to iCloud. This happens automatically in the background without you even having to think about it, and you can restore such backups when setting up a device simply by logging in with your Apple ID. Personal Data In the days of PalmPilots, people would use desktop programs like iTunes to sync their email, contacts, and calendar events with their mobile devices. You probably shouldn’t have to sync this data form your computer. Just sign into your email account — for example, a Gmail account — on your device and iOS will automatically pull your email, contacts, and calendar events from your associated account. Photos Rather than connecting your iOS device to your computer and syncing photos from it, you can use an app that automatically uploads your photos to a web service. Dropbox, Google+, and even Flickr all have this feature in their apps. You’ll be able to access your photos from any computer and have a backup copy without any syncing required. You may still need to use iTunes if you want to sync local music without paying for iTunes Match or copy local video files to your device. Copying large local files over is the only real scenario where you’d need iTunes. If you don’t need to copy such files over, you can go ahead and uninstall iTunes from your Windows PC if you like. You shouldn’t need it.     

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  • External File Upload Optimizations for Windows Azure

    - by rgillen
    [Cross posted from here: http://rob.gillenfamily.net/post/External-File-Upload-Optimizations-for-Windows-Azure.aspx] I’m wrapping up a bit of the work we’ve been doing on data movement optimizations for cloud computing and the latest set of data yielded some interesting points I thought I’d share. The work done here is not really rocket science but may, in some ways, be slightly counter-intuitive and therefore seemed worthy of posting. Summary: for those who don’t like to read detailed posts or don’t have time, the synopsis is that if you are uploading data to Azure, block your data (even down to 1MB) and upload in parallel. Set your block size based on your source file size, but if you must choose a fixed value, use 1MB. Following the above will result in significant performance gains… upwards of 10x-24x and a reduction in overall file transfer time of upwards of 90% (eg, uploading a 1GB file averaged 46.37 minutes prior to optimizations and averaged 1.86 minutes afterwards). Detail: For those of you who want more detail, or think that the claims at the end of the preceding paragraph are over-reaching, what follows is information and code supporting these claims. As the title would indicate, these tests were run from our research facility pointing to the Azure cloud (specifically US North Central as it is physically closest to us) and do not represent intra-cloud results… we have performed intra-cloud tests and the overall results are similar in notion but the data rates are significantly different as well as the tipping points for the various block sizes… this will be detailed separately). We started by building a very simple console application that would loop through a directory and upload each file to Azure storage. This application used the shipping storage client library from the 1.1 version of the azure tools. The only real variation from the client library is that we added code to collect and record the duration (in ms) and size (in bytes) for each file transferred. The code is available here. We then created a directory that had a collection of files for the following sizes: 2KB, 32KB, 64KB, 128KB, 512KB, 1MB, 5MB, 10MB, 25MB, 50MB, 100MB, 250MB, 500MB, 750MB, and 1GB (50 files for each size listed). These files contained randomly-generated binary data and do not benefit from compression (a separate discussion topic). Our file generation tool is available here. The baseline was established by running the application described above against the directory containing all of the data files. This application uploads the files in a random order so as to avoid transferring all of the files of a given size sequentially and thereby spreading the affects of periodic Internet delays across the collection of results.  We then ran some scripts to split the resulting data and generate some reports. The raw data collected for our non-optimized tests is available via the links in the Related Resources section at the bottom of this post. For each file size, we calculated the average upload time (and standard deviation) and the average transfer rate (and standard deviation). As you likely are aware, transferring data across the Internet is susceptible to many transient delays which can cause anomalies in the resulting data. It is for this reason that we randomized the order of source file processing as well as executed the tests 50x for each file size. We expect that these steps will yield a sufficiently balanced set of results. Once the baseline was collected and analyzed, we updated the test harness application with some methods to split the source file into user-defined block sizes and then to upload those blocks in parallel (using the PutBlock() method of Azure storage). The parallelization was handled by simply relying on the Parallel Extensions to .NET to provide a Parallel.For loop (see linked source for specific implementation details in Program.cs, line 173 and following… less than 100 lines total). Once all of the blocks were uploaded, we called PutBlockList() to assemble/commit the file in Azure storage. For each block transferred, the MD5 was calculated and sent ensuring that the bits that arrived matched was was intended. The timer for the blocked/parallelized transfer method wraps the entire process (source file splitting, block transfer, MD5 validation, file committal). A diagram of the process is as follows: We then tested the affects of blocking & parallelizing the transfers by running the updated application against the same source set and did a parameter sweep on the block size including 256KB, 512KB, 1MB, 2MB, and 4MB (our assumption was that anything lower than 256KB wasn’t worth the trouble and 4MB is the maximum size of a block supported by Azure). The raw data for the parallel tests is available via the links in the Related Resources section at the bottom of this post. This data was processed and then compared against the single-threaded / non-optimized transfer numbers and the results were encouraging. The Excel version of the results is available here. Two semi-obvious points need to be made prior to reviewing the data. The first is that if the block size is larger than the source file size you will end up with a “negative optimization” due to the overhead of attempting to block and parallelize. The second is that as the files get smaller, the clock-time cost of blocking and parallelizing (overhead) is more apparent and can tend towards negative optimizations. For this reason (and is supported in the raw data provided in the linked worksheet) the charts and dialog below ignore source file sizes less than 1MB. (click chart for full size image) The chart above illustrates some interesting points about the results: When the block size is smaller than the source file, performance increases but as the block size approaches and then passes the source file size, you see decreasing benefit to the point of negative gains (see the values for the 1MB file size) For some of the moderately-sized source files, small blocks (256KB) are best As the size of the source file gets larger (see values for 50MB and up), the smallest block size is not the most efficient (presumably due, at least in part, to the increased number of blocks, increased number of individual transfer requests, and reassembly/committal costs). Once you pass the 250MB source file size, the difference in rate for 1MB to 4MB blocks is more-or-less constant The 1MB block size gives the best average improvement (~16x) but the optimal approach would be to vary the block size based on the size of the source file.    (click chart for full size image) The above is another view of the same data as the prior chart just with the axis changed (x-axis represents file size and plotted data shows improvement by block size). It again highlights the fact that the 1MB block size is probably the best overall size but highlights the benefits of some of the other block sizes at different source file sizes. This last chart shows the change in total duration of the file uploads based on different block sizes for the source file sizes. Nothing really new here other than this view of the data highlights the negative affects of poorly choosing a block size for smaller files.   Summary What we have found so far is that blocking your file uploads and uploading them in parallel results in significant performance improvements. Further, utilizing extension methods and the Task Parallel Library (.NET 4.0) make short work of altering the shipping client library to provide this functionality while minimizing the amount of change to existing applications that might be using the client library for other interactions.   Related Resources Source code for upload test application Source code for random file generator ODatas feed of raw data from non-optimized transfer tests Experiment Metadata Experiment Datasets 2KB Uploads 32KB Uploads 64KB Uploads 128KB Uploads 256KB Uploads 512KB Uploads 1MB Uploads 5MB Uploads 10MB Uploads 25MB Uploads 50MB Uploads 100MB Uploads 250MB Uploads 500MB Uploads 750MB Uploads 1GB Uploads Raw Data OData feeds of raw data from blocked/parallelized transfer tests Experiment Metadata Experiment Datasets Raw Data 256KB Blocks 512KB Blocks 1MB Blocks 2MB Blocks 4MB Blocks Excel worksheet showing summarizations and comparisons

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  • Christmas in the Clouds

    - by andrewbrust
    I have been spending the last 2 weeks immersing myself in a number of Windows Azure and SQL Azure technologies.  And in setting up a new business (I’ll speak more about that in the future), I have also become a customer of Microsoft’s BPOS (Business Productivity Online Services).  In short, it has been a fortnight of Microsoft cloud computing. On the Azure side, I’ve looked, of course, at Web Roles and Worker Roles.  But I’ve also looked at Azure Storage’s REST API (including coding to it directly), I’ve looked at Azure Drive and the new VM Role; I’ve looked quite a bit at SQL Azure (including the project “Houston” Silverlight UI) and I’ve looked at SQL Azure labs’ OData service too. I’ve also looked at DataMarket and its integration with both PowerPivot and native Excel.  Then there’s AppFabric Caching, SQL Azure Reporting (what I could learn of it) and the Visual Studio tooling for Azure, including the storage of certificate-based credentials.  And to round it out with some user stuff, on the BPOS side, I’ve been working with Exchange Online, SharePoint Online and LiveMeeting. I have to say I like a lot of what I’ve been seeing.  Azure’s not perfect, and BPOS certainly isn’t either.  But there’s good stuff in all these products, and there’s a lot of value. Azure Goes Deep Most people know that Web and Worker roles put the platform in charge of spinning virtual machines up and down, and keeping them up to date. But you can go way beyond that now.  The still-in-beta VM Role gives you the power to craft the machine (much as does Amazon’s EC2), though it takes away the platform’s self-managing attributes.  It still spins instances up and down, making drive storage non-durable, but Azure Drive gives you the ability to store VHD files as blobs and mount them as virtual hard drives that are readable and writeable.  Whether with Azure Storage or SQL Azure, Azure does data.  And OData is everywhere.  Azure Table Storage supports an OData Interface.  So does SQL Azure and so does DataMarket (the former project “Dallas”).  That means that Azure data repositories aren’t just straightforward to provision and configure…they’re also easy to program against, from just about any programming environment, in a RESTful manner.  And for more .NET-centric implementations, Azure AppFabric caching takes the technology formerly known as “Velocity” and throws it up into the cloud, speeding data access even more. Snapping in Place Once you get the hang of it, this stuff just starts to work in a way that becomes natural to understand.  I wasn’t expecting that, and I was really happy to discover it. In retrospect, I am not surprised, because I think the various Azure teams are the center of gravity for Redmond’s innovation right now.  The products belie this and so do my observations of the product teams’ motivation and high morale.  It is really good to see this; Microsoft needs to lead somewhere, and they need to be seen as the underdog while doing so.  With Azure, both requirements are in place.   BPOS: Bad Acronym, Easy Setup BPOS is about products you already know; Exchange, SharePoint, Live Meeting and Office Communications Server.  As such, it’s hard not to be underwhelmed by BPOS.  Until you realize how easy it makes it to get all that stuff set up.  I would say that from sign-up to productive use took me about 45 minutes…and that included the time necessary to wrestle with my DNS provider, set up Outlook and my SmartPhone up to talk to the Exchange account, create my SharePoint site collection, and configure the Outlook Conferencing add-in to talk to the provisioned Live Meeting account. Never before did I think setting up my own Exchange mail could come anywhere close to the simplicity of setting up an SMTP/POP account, and yet BPOS actually made it faster.   What I want from my Azure Christmas Next Year Not everything about Microsoft’s cloud is good.  I close this post with a list of things I’d like to see addressed: BPOS offerings are still based on the 2007 Wave of Microsoft server technologies.  We need to get to 2010, and fast.  Arguably, the 2010 products should have been released to the off-premises channel before the on-premise sone.  Office 365 can’t come fast enough. Azure’s Internet tooling and domain naming, is scattered and confusing.  Deployed ASP.NET applications go to cloudapp.net; SQL Azure and Azure storage work off windows.net.  The Azure portal and Project Houston are at azure.com.  Then there’s appfabriclabs.com and sqlazurelabs.com.  There is a new Silverlight portal that replaces most, but not all of the HTML ones.  And Project Houston is Silvelright-based too, though separate from the Silverlight portal tooling. Microsoft is the king off tooling.  They should not make me keep an entire OneNote notebook full of portal links, account names, access keys, assemblies and namespaces and do so much CTRL-C/CTRL-V work.  I’d like to see more project templates, have them automatically reference the appropriate assemblies, generate the right using/Imports statements and prime my config files with the right markup.  Then I want a UI that lets me log in with my Live ID and pick the appropriate project, database, namespace and key string to get set up fast. Beta programs, if they’re open, should onboard me quickly.  I know the process is difficult and everyone’s going as fast as they can.  But I don’t know why it’s so difficult or why it takes so long.  Getting developers up to speed on new features quickly helps popularize the platform.  Make this a priority. Make Azure accessible from the simplicity platforms, i.e. ASP.NET Web Pages (Razor) and LightSwitch.  Support .NET 4 now.  Make WebMatrix, IIS Express and SQL Compact work with the Azure development fabric. Have HTML helpers make Azure programming easier.  Have LightSwitch work with SQL Azure and not require SQL Express.  LightSwitch has some promising Azure integration now.  But we need more.  WebMatrix has none and that’s just silly, now that the Extra Small Instance is being introduced. The Windows Azure Platform Training Kit is great.  But I want Microsoft to make it even better and I want them to evangelize it much more aggressively.  There’s a lot of good material on Azure development out there, but it’s scattered in the same way that the platform is.   The Training Kit ties a lot of disparate stuff together nicely.  Make it known. Should Old Acquaintance Be Forgot All in all, diving deep into Azure was a good way to end the year.  Diving deeper into Azure should a great way to spend next year, not just for me, but for Microsoft too.

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  • Oracle OpenWorld 2013 – Wrap up by Sven Bernhardt

    - by JuergenKress
    OOW 2013 is over and we’re heading home, so it is time to lean back and reflecting about the impressions we have from the conference. First of all: OOW was great! It was a pleasure to be a part of it. As already mentioned in our last blog article: It was the biggest OOW ever. Parallel to the conference the America’s Cup took place in San Francisco and the Oracle Team America won. Amazing job by the team and again congratulations from our side Back to the conference. The main topics for us are: Oracle SOA / BPM Suite 12c Adaptive Case management (ACM) Big Data Fast Data Cloud Mobile Below we will go a little more into detail, what are the key takeaways regarding the mentioned points: Oracle SOA / BPM Suite 12c During the five days at OOW, first details of the upcoming major release of Oracle SOA Suite 12c and Oracle BPM Suite 12c have been introduced. Some new key features are: Managed File Transfer (MFT) for transferring big files from a source to a target location Enhanced REST support by introducing a new REST binding Introduction of a generic cloud adapter, which can be used to connect to different cloud providers, like Salesforce Enhanced analytics with BAM, which has been totally reengineered (BAM Console now also runs in Firefox!) Introduction of templates (OSB pipelines, component templates, BPEL activities templates) EM as a single monitoring console OSB design-time integration into JDeveloper (Really great!) Enterprise modeling capabilities in BPM Composer These are only a few points from what is coming with 12c. We are really looking forward for the new realese to come out, because this seems to be really great stuff. The suite becomes more and more integrated. From 10g to 11g it was an evolution in terms of developing SOA-based applications. With 12c, Oracle continues it’s way – very impressive. Adaptive Case Management Another fantastic topic was Adaptive Case Management (ACM). The Oracle PMs did a great job especially at the demo grounds in showing the upcoming Case Management UI (will be available in 11g with the next BPM Suite MLR Patch), the roadmap and the differences between traditional business process modeling. They have been very busy during the conference because a lot of partners and customers have been interested Big Data Big Data is one of the current hype themes. Because of huge data amounts from different internal or external sources, the handling of these data becomes more and more challenging. Companies have a need for analyzing the data to optimize their business. The challenge is here: the amount of data is growing daily! To store and analyze the data efficiently, it is necessary to have a scalable and flexible infrastructure. Here it is important that hardware and software are engineered to work together. Therefore several new features of the Oracle Database 12c, like the new in-memory option, have been presented by Larry Ellison himself. From a hardware side new server machines like Fujitsu M10 or new processors, such as Oracle’s new M6-32 have been announced. The performance improvements, when using one of these hardware components in connection with the improved software solutions were really impressive. For more details about this, please take look at our previous blog post. Regarding Big Data, Oracle also introduced their Big Data architecture, which consists of: Oracle Big Data Appliance that is preconfigured with Hadoop Oracle Exdata which stores a huge amount of data efficently, to achieve optimal query performance Oracle Exalytics as a fast and scalable Business analytics system Analysis of the stored data can be performed using SQL, by streaming the data directly from Hadoop to an Oracle Database 12c. Alternatively the analysis can be directly implemented in Hadoop using “R”. In addition Oracle BI Tools can be used to analyze the data. Fast Data Fast Data is a complementary approach to Big Data. A huge amount of mostly unstructured data comes in via different channels with a high frequency. The analysis of these data streams is also important for companies, because the incoming data has to be analyzed regarding business-relevant patterns in real-time. Therefore these patterns must be identified efficiently and performant. To do so, in-memory grid solutions in combination with Oracle Coherence and Oracle Event Processing demonstrated very impressive how efficient real-time data processing can be. One example for Fast Data solutions that was shown during the OOW was the analysis of twitter streams regarding customer satisfaction. The feeds with negative words like “bad” or “worse” have been filtered and after a defined treshold has been reached in a certain timeframe, a business event was triggered. Cloud Another key trend in the IT market is of course Cloud Computing and what it means for companies and their businesses. Oracle announced their Cloud strategy and vision – companies can focus on their real business while all of the applications are available via Cloud. This also includes Oracle Database or Oracle Weblogic, so that companies can also build, deploy and run their own applications within the cloud. Three different approaches have been introduced: Infrastructure as a Service (IaaS) Platform as a Service (PaaS) Software as a Service (SaaS) Using the IaaS approach only the infrastructure components will be managed in the Cloud. Customers will be very flexible regarding memory, storage or number of CPUs because those parameters can be adjusted elastically. The PaaS approach means that besides the infrastructure also the platforms (such as databases or application servers) necessary for running applications will be provided within the Cloud. Here customers can also decide, if installation and management of these infrastructure components should be done by Oracle. The SaaS approach describes the most complete one, hence all applications a company uses are managed in the Cloud. Oracle is planning to provide all of their applications, like ERP systems or HR applications, as Cloud services. In conclusion this seems to be a very forward-thinking strategy, which opens up new possibilities for customers to manage their infrastructure and applications in a flexible, scalable and future-oriented manner. As you can see, our OOW days have been very very interresting. We collected many helpful informations for our projects. The new innovations presented at the confernce are great and being part of this was even greater! We are looking forward to next years’ conference! Links: http://www.oracle.com/openworld/index.html http://thecattlecrew.wordpress.com/2013/09/23/first-impressions-from-oracle-open-world-2013 SOA & BPM Partner Community For regular information on Oracle SOA Suite become a member in the SOA & BPM Partner Community for registration please visit www.oracle.com/goto/emea/soa (OPN account required) If you need support with your account please contact the Oracle Partner Business Center. Blog Twitter LinkedIn Facebook Wiki Mix Forum Technorati Tags: cattleCrew,Sven Bernhard,OOW2013,SOA Community,Oracle SOA,Oracle BPM,Community,OPN,Jürgen Kress

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  • How to create a virtual network with Azure Connect

    - by Herve Roggero
    If you are trying to establish a virtual network between machines located in disparate networks, you can either use VPN, Virtual Network or Azure Connect. If you want to establish a connection between machines located in Windows Azure, you should consider using the Virtual Network service. If you want to establish a connection between local machines and Virtual Machines in Windows Azure, you may be able to use your existing VPN device (assuming you have one), as long as the device is supported by Microsoft. If the VPN device you are using isn’t supported, or if you are trying to create a virtual network between machines from disparate networks (such as machines located in another cloud provider), you can use Azure Connect. This blog post explains how Azure Connect can help you create virtual networks between multiple servers in the cloud, various servers in different cloud environments, and on-premise. Note: Azure Connect is currently in Technical Preview. About Azure Connect Let’s do a quick review of Azure Connect. This technology implements an IPSec tunnel from machines to to a relay service located in the Microsoft cloud (Azure). So in essence, Azure Connect doesn’t provide a point-to-point connection between machines; the network communication is tunneled through the relay service. The relay service in turn offers a mechanism to enforce basic communication rules that you define through Groups. We will review this later. You could network two or more VMs in the Azure cloud (although you should consider using a Virtual Network if you go this route), or servers in the Azure cloud and other machines in the Amazon cloud for example, or even two or more on-premise servers located in different locations for which a direct network connection is not an option. You can place any number of machines in your topology. Azure Connect gives you great flexibility on how you want to build your virtual network across various environments. So Azure Connect makes sense when you want to: Connect machines located in different cloud providers Connect on-premise machines running in different locations Connect Azure VMs with on-premise (if you do not have a VPN device, or if your device is not supported) Connect Azure Roles (Worker Roles, Web Roles) with on-premise servers or in other cloud providers The diagram below shows you a high level network topology that involves machines in the Windows Azure cloud, other cloud providers and on-premise. You should note that the only required component in this diagram is the Relay itself. The other machines are optional (although your network is useful only if you have two or more machines involved). Relay agents are currently available in three geographic areas: US, Europe and Asia. You can change which region you want to use in the Windows Azure management portal. High Level Network Topology With Azure Connect Azure Connect Agent Azure Connect establishes a virtual network and creates virtual adapters on your machines; these virtual adapters communicate through the Relay using IPSec. This is achieved by installing an agent (the Azure Connect Agent) on all the machines you want in your network topology. However, you do not need to install the agent on Worker Roles and Web Roles; that’s because the agent is already installed for you. Any other machine, including Virtual Machines in Windows Azure, needs the agent installed.  To install the agent, simply go to your Windows Azure portal (http://windows.azure.com) and click on Networks on the bottom left panel. You will see a list of subscriptions under Connect. If you select a subscription, you will be able to click on the Install Local Endpoint icon on top. Clicking on this icon will begin the download and installation process for the agent. Activating Roles for Azure Connect As previously mentioned, you do not need to install the Azure Connect Agent on Worker Roles and Web Roles because it is already loaded. However, you do need to activate them if you want the roles to participate in your network topology. To do this, you will need to click on the Get Activation Token icon. The activation token must then be copied and placed in the configuration file of your roles. For more information on how to perform this step, visit MSDN at http://msdn.microsoft.com/en-us/library/windowsazure/gg432964.aspx. Firewall Rules Note that specific firewall rules must exist to allow the agent to communicate through the Relay. You will need to allow TCP 443 and ICMPv6. For additional information, please visit MSDN at http://msdn.microsoft.com/en-us/library/windowsazure/gg433061.aspx. CA Certificates You can optionally require agents to sign their activation request with the Relay using a trusted certificate issued by a Certificate Authority (CA). Click on Activation Options to learn more. Groups To create your network topology you must first create a group. A group represents a logical container of endpoints (or machines) that can communicate through the Relay. You can create multiple groups allowing you to manage network communication differently. For example you could create a DEVELOPMENT group and a PRODUCTION group. To add an endpoint you must first install an agent that will create a virtual adapter on the machine on which it is installed (as discussed in the previous section). Once you have created a group and installed the agents, the machines will appear in the Windows Azure management portal and you can start assigning machines to groups. The next figure shows you that I created a group called LocalGroup and assigned two machines (both on-premise) to that group. Groups and Computers in Azure Connect As I mentioned previously you can allow these machines to establish a network connection. To do this, you must enable the Interconnected option in the group. The following diagram shows you the definition of the group. In this topology I chose to include local machines only, but I could also add worker roles and web roles in the Azure Roles section (you must first activate your roles, as discussed previously). You could also add other Groups, allowing you to manage inter-group communication. Defining a Group in Azure Connect Testing the Connection Now that my agents have been installed on my two machines, the group defined and the Interconnected option checked, I can test the connection between my machines. The next screenshot shows you that I sent a PING request to DEVLAP02 from DEVDSK02. The PING request was successful. Note however that the time is in the hundreds of milliseconds on average. That is to be expected because the machines are connecting through the Relay located in the cloud. Going through the Relay introduces an extra hop in the communication chain, so if your systems rely on high performance, you may want to conduct some basic performance tests. Sending a PING Request Through The Relay Conclusion As you can see, creating a network topology between machines using the Azure Connect service is simple. It took me less than five minutes to create the above configuration, including the time it took to install the Azure Connect agents on the two machines. The flexibility of Azure Connect allows you to create a virtual network between disparate environments, as long as your operating systems are supported by the agent. For more information on Azure Connect, visit the MSDN website at http://msdn.microsoft.com/en-us/library/windowsazure/gg432997.aspx. About Herve Roggero Herve Roggero, Windows Azure MVP, is the founder of Blue Syntax Consulting, a company specialized in cloud computing products and services. Herve's experience includes software development, architecture, database administration and senior management with both global corporations and startup companies. Herve holds multiple certifications, including an MCDBA, MCSE, MCSD. He also holds a Master's degree in Business Administration from Indiana University. Herve is the co-author of "PRO SQL Azure" from Apress and runs the Azure Florida Association (on LinkedIn: http://www.linkedin.com/groups?gid=4177626). For more information on Blue Syntax Consulting, visit www.bluesyntax.net. Special Thanks I would like thank those that helped me figure out how Azure Connect works: Marcel Meijer - http://blogs.msmvps.com/marcelmeijer/ Michael Wood - Http://www.mvwood.com Glenn Block - http://www.codebetter.com/glennblock Yves Goeleven - http://cloudshaper.wordpress.com/ Sandrino Di Mattia - http://fabriccontroller.net/ Mike Martin - http://techmike2kx.wordpress.com

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  • HTG Explains: Why Does Rebooting a Computer Fix So Many Problems?

    - by Chris Hoffman
    Ask a geek how to fix a problem you’ve having with your Windows computer and they’ll likely ask “Have you tried rebooting it?” This seems like a flippant response, but rebooting a computer can actually solve many problems. So what’s going on here? Why does resetting a device or restarting a program fix so many problems? And why don’t geeks try to identify and fix problems rather than use the blunt hammer of “reset it”? This Isn’t Just About Windows Bear in mind that this soltion isn’t just limited to Windows computers, but applies to all types of computing devices. You’ll find the advice “try resetting it” applied to wireless routers, iPads, Android phones, and more. This same advice even applies to software — is Firefox acting slow and consuming a lot of memory? Try closing it and reopening it! Some Problems Require a Restart To illustrate why rebooting can fix so many problems, let’s take a look at the ultimate software problem a Windows computer can face: Windows halts, showing a blue screen of death. The blue screen was caused by a low-level error, likely a problem with a hardware driver or a hardware malfunction. Windows reaches a state where it doesn’t know how to recover, so it halts, shows a blue-screen of death, gathers information about the problem, and automatically restarts the computer for you . This restart fixes the blue screen of death. Windows has gotten better at dealing with errors — for example, if your graphics driver crashes, Windows XP would have frozen. In Windows Vista and newer versions of Windows, the Windows desktop will lose its fancy graphical effects for a few moments before regaining them. Behind the scenes, Windows is restarting the malfunctioning graphics driver. But why doesn’t Windows simply fix the problem rather than restarting the driver or the computer itself?  Well, because it can’t — the code has encountered a problem and stopped working completely, so there’s no way for it to continue. By restarting, the code can start from square one and hopefully it won’t encounter the same problem again. Examples of Restarting Fixing Problems While certain problems require a complete restart because the operating system or a hardware driver has stopped working, not every problem does. Some problems may be fixable without a restart, though a restart may be the easiest option. Windows is Slow: Let’s say Windows is running very slowly. It’s possible that a misbehaving program is using 99% CPU and draining the computer’s resources. A geek could head to the task manager and look around, hoping to locate the misbehaving process an end it. If an average user encountered this same problem, they could simply reboot their computer to fix it rather than dig through their running processes. Firefox or Another Program is Using Too Much Memory: In the past, Firefox has been the poster child for memory leaks on average PCs. Over time, Firefox would often consume more and more memory, getting larger and larger and slowing down. Closing Firefox will cause it to relinquish all of its memory. When it starts again, it will start from a clean state without any leaked memory. This doesn’t just apply to Firefox, but applies to any software with memory leaks. Internet or Wi-Fi Network Problems: If you have a problem with your Wi-Fi or Internet connection, the software on your router or modem may have encountered a problem. Resetting the router — just by unplugging it from its power socket and then plugging it back in — is a common solution for connection problems. In all cases, a restart wipes away the current state of the software . Any code that’s stuck in a misbehaving state will be swept away, too. When you restart, the computer or device will bring the system up from scratch, restarting all the software from square one so it will work just as well as it was working before. “Soft Resets” vs. “Hard Resets” In the mobile device world, there are two types of “resets” you can perform. A “soft reset” is simply restarting a device normally — turning it off and then on again. A “hard reset” is resetting its software state back to its factory default state. When you think about it, both types of resets fix problems for a similar reason. For example, let’s say your Windows computer refuses to boot or becomes completely infected with malware. Simply restarting the computer won’t fix the problem, as the problem is with the files on the computer’s hard drive — it has corrupted files or malware that loads at startup on its hard drive. However, reinstalling Windows (performing a “Refresh or Reset your PC” operation in Windows 8 terms) will wipe away everything on the computer’s hard drive, restoring it to its formerly clean state. This is simpler than looking through the computer’s hard drive, trying to identify the exact reason for the problems or trying to ensure you’ve obliterated every last trace of malware. It’s much faster to simply start over from a known-good, clean state instead of trying to locate every possible problem and fix it. Ultimately, the answer is that “resetting a computer wipes away the current state of the software, including any problems that have developed, and allows it to start over from square one.” It’s easier and faster to start from a clean state than identify and fix any problems that may be occurring — in fact, in some cases, it may be impossible to fix problems without beginning from that clean state. Image Credit: Arria Belli on Flickr, DeclanTM on Flickr     

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  • DBA Best Practices - A Blog Series: Episode 1 - Backups

    - by Argenis
      This blog post is part of the DBA Best Practices series, on which various topics of concern for daily database operations are discussed. Your feedback and comments are very much welcome, so please drop by the comments section and be sure to leave your thoughts on the subject. Morning Coffee When I was a DBA, the first thing I did when I sat down at my desk at work was checking that all backups had completed successfully. It really was more of a ritual, since I had a dual system in place to check for backup completion: 1) the scheduled agent jobs to back up the databases were set to alert the NOC in failure, and 2) I had a script run from a central server every so often to check for any backup failures. Why the redundancy, you might ask. Well, for one I was once bitten by the fact that database mail doesn't work 100% of the time. Potential causes for failure include issues on the SMTP box that relays your server email, firewall problems, DNS issues, etc. And so to be sure that my backups completed fine, I needed to rely on a mechanism other than having the servers do the taking - I needed to interrogate the servers and ask each one if an issue had occurred. This is why I had a script run every so often. Some of you might have monitoring tools in place like Microsoft System Center Operations Manager (SCOM) or similar 3rd party products that would track all these things for you. But at that moment, we had no resort but to write our own Powershell scripts to do it. Now it goes without saying that if you don't have backups in place, you might as well find another career. Your most sacred job as a DBA is to protect the data from a disaster, and only properly safeguarded backups can offer you peace of mind here. "But, we have a cluster...we don't need backups" Sadly I've heard this line more than I would have liked to. You need to understand that a cluster is comprised of shared storage, and that is precisely your single point of failure. A cluster will protect you from an issue at the Operating System level, and also under an outage of any SQL-related service or dependent devices. But it will most definitely NOT protect you against corruption, nor will it protect you against somebody deleting data from a table - accidentally or otherwise. Backup, fine. How often do I take a backup? The answer to this is something you will hear frequently when working with databases: it depends. What does it depend on? For one, you need to understand how much data your business is willing to lose. This is what's called Recovery Point Objective, or RPO. If you don't know how much data your business is willing to lose, you need to have an honest and realistic conversation about data loss expectations with your customers, internal or external. From my experience, their first answer to the question "how much data loss can you withstand?" will be "zero". In that case, you will need to explain how zero data loss is very difficult and very costly to achieve, even in today's computing environments. Do you want to go ahead and take full backups of all your databases every hour, or even every day? Probably not, because of the impact that taking a full backup can have on a system. That's what differential and transaction log backups are for. Have I answered the question of how often to take a backup? No, and I did that on purpose. You need to think about how much time you have to recover from any event that requires you to restore your databases. This is what's called Recovery Time Objective. Again, if you go ask your customer how long of an outage they can withstand, at first you will get a completely unrealistic number - and that will be your starting point for discussing a solution that is cost effective. The point that I'm trying to get across is that you need to have a plan. This plan needs to be practiced, and tested. Like a football playbook, you need to rehearse the moves you'll perform when the time comes. How often is up to you, and the objective is that you feel better about yourself and the steps you need to follow when emergency strikes. A backup is nothing more than an untested restore Backups are files. Files are prone to corruption. Put those two together and realize how you feel about those backups sitting on that network drive. When was the last time you restored any of those? Restoring your backups on another box - that, by the way, doesn't have to match the specs of your production server - will give you two things: 1) peace of mind, because now you know that your backups are good and 2) a place to offload your consistency checks with DBCC CHECKDB or any of the other DBCC commands like CHECKTABLE or CHECKCATALOG. This is a great strategy for VLDBs that cannot withstand the additional load created by the consistency checks. If you choose to offload your consistency checks to another server though, be sure to run DBCC CHECKDB WITH PHYSICALONLY on the production server, and if you're using SQL Server 2008 R2 SP1 CU4 and above, be sure to enable traceflags 2562 and/or 2549, which will speed up the PHYSICALONLY checks further - you can read more about this enhancement here. Back to the "How Often" question for a second. If you have the disk, and the network latency, and the system resources to do so, why not backup the transaction log often? As in, every 5 minutes, or even less than that? There's not much downside to doing it, as you will have to clear the log with a backup sooner than later, lest you risk running out space on your tlog, or even your drive. The one drawback to this approach is that you will have more files to deal with at restore time, and processing each file will add a bit of extra time to the entire process. But it might be worth that time knowing that you minimized the amount of data lost. Again, test your plan to make sure that it matches your particular needs. Where to back up to? Network share? Locally? SAN volume? This is another topic where everybody has a favorite choice. So, I'll stick to mentioning what I like to do and what I consider to be the best practice in this regard. I like to backup to a SAN volume, i.e., a drive that actually lives in the SAN, and can be easily attached to another server in a pinch, saving you valuable time - you wouldn't need to restore files on the network (slow) or pull out drives out a dead server (been there, done that, it’s also slow!). The key is to have a copy of those backup files made quickly, and, if at all possible, to a remote target on a different datacenter - or even the cloud. There are plenty of solutions out there that can help you put such a solution together. That right there is the first step towards a practical Disaster Recovery plan. But there's much more to DR, and that's material for a different blog post in this series.

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  • DBA Best Practices - A Blog Series: Episode 1 - Backups

    - by Argenis
      This blog post is part of the DBA Best Practices series, on which various topics of concern for daily database operations are discussed. Your feedback and comments are very much welcome, so please drop by the comments section and be sure to leave your thoughts on the subject. Morning Coffee When I was a DBA, the first thing I did when I sat down at my desk at work was checking that all backups have completed successfully. It really was more of a ritual, since I had a dual system in place to check for backup completion: 1) the scheduled agent jobs to back up the databases were set to alert the NOC in failure, and 2) I had a script run from a central server every so often to check for any backup failures. Why the redundancy, you might ask. Well, for one I was once bitten by the fact that database mail doesn't work 100% of the time. Potential causes for failure include issues on the SMTP box that relays your server email, firewall problems, DNS issues, etc. And so to be sure that my backups completed fine, I needed to rely on a mechanism other than having the servers do the taking - I needed to interrogate the servers and ask each one if an issue had occurred. This is why I had a script run every so often. Some of you might have monitoring tools in place like Microsoft System Center Operations Manager (SCOM) or similar 3rd party products that would track all these things for you. But at that moment, we had no resort but to write our own Powershell scripts to do it. Now it goes without saying that if you don't have backups in place, you might as well find another career. Your most sacred job as a DBA is to protect the data from a disaster, and only properly safeguarded backups can offer you peace of mind here. "But, we have a cluster...we don't need backups" Sadly I've heard this line more than I would have liked to. You need to understand that a cluster is comprised of shared storage, and that is precisely your single point of failure. A cluster will protect you from an issue at the Operating System level, and also under an outage of any SQL-related service or dependent devices. But it will most definitely NOT protect you against corruption, nor will it protect you against somebody deleting data from a table - accidentally or otherwise. Backup, fine. How often do I take a backup? The answer to this is something you will hear frequently when working with databases: it depends. What does it depend on? For one, you need to understand how much data your business is willing to lose. This is what's called Recovery Point Objective, or RPO. If you don't know how much data your business is willing to lose, you need to have an honest and realistic conversation about data loss expectations with your customers, internal or external. From my experience, their first answer to the question "how much data loss can you withstand?" will be "zero". In that case, you will need to explain how zero data loss is very difficult and very costly to achieve, even in today's computing environments. Do you want to go ahead and take full backups of all your databases every hour, or even every day? Probably not, because of the impact that taking a full backup can have on a system. That's what differential and transaction log backups are for. Have I answered the question of how often to take a backup? No, and I did that on purpose. You need to think about how much time you have to recover from any event that requires you to restore your databases. This is what's called Recovery Time Objective. Again, if you go ask your customer how long of an outage they can withstand, at first you will get a completely unrealistic number - and that will be your starting point for discussing a solution that is cost effective. The point that I'm trying to get across is that you need to have a plan. This plan needs to be practiced, and tested. Like a football playbook, you need to rehearse the moves you'll perform when the time comes. How often is up to you, and the objective is that you feel better about yourself and the steps you need to follow when emergency strikes. A backup is nothing more than an untested restore Backups are files. Files are prone to corruption. Put those two together and realize how you feel about those backups sitting on that network drive. When was the last time you restored any of those? Restoring your backups on another box - that, by the way, doesn't have to match the specs of your production server - will give you two things: 1) peace of mind, because now you know that your backups are good and 2) a place to offload your consistency checks with DBCC CHECKDB or any of the other DBCC commands like CHECKTABLE or CHECKCATALOG. This is a great strategy for VLDBs that cannot withstand the additional load created by the consistency checks. If you choose to offload your consistency checks to another server though, be sure to run DBCC CHECKDB WITH PHYSICALONLY on the production server, and if you're using SQL Server 2008 R2 SP1 CU4 and above, be sure to enable traceflags 2562 and/or 2549, which will speed up the PHYSICALONLY checks further - you can read more about this enhancement here. Back to the "How Often" question for a second. If you have the disk, and the network latency, and the system resources to do so, why not backup the transaction log often? As in, every 5 minutes, or even less than that? There's not much downside to doing it, as you will have to clear the log with a backup sooner than later, lest you risk running out space on your tlog, or even your drive. The one drawback to this approach is that you will have more files to deal with at restore time, and processing each file will add a bit of extra time to the entire process. But it might be worth that time knowing that you minimized the amount of data lost. Again, test your plan to make sure that it matches your particular needs. Where to back up to? Network share? Locally? SAN volume? This is another topic where everybody has a favorite choice. So, I'll stick to mentioning what I like to do and what I consider to be the best practice in this regard. I like to backup to a SAN volume, i.e., a drive that actually lives in the SAN, and can be easily attached to another server in a pinch, saving you valuable time - you wouldn't need to restore files on the network (slow) or pull out drives out a dead server (been there, done that, it’s also slow!). The key is to have a copy of those backup files made quickly, and, if at all possible, to a remote target on a different datacenter - or even the cloud. There are plenty of solutions out there that can help you put such a solution together. That right there is the first step towards a practical Disaster Recovery plan. But there's much more to DR, and that's material for a different blog post in this series.

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  • Projected Results

    - by Sylvie MacKenzie, PMP
    Excerpt from PROFIT - ORACLE - by Monica Mehta Yasser Mahmud has seen a revolution in project management over the past decade. During that time, the former Primavera product strategist (who joined Oracle when his company was acquired in 2008) has not only observed a transformation in the way IT systems support corporate projects but the role project portfolio management (PPM) plays in the enterprise. “15 years ago project management was the domain of project management office (PMO),” Mahmud recalls of earlier days. “But over the course of the past decade, we've seen it transform into a mission critical enterprise discipline, that has made Primavera indispensable in the board room. Now, as a senior manager, a board member, or a C-level executive you have direct and complete visibility into what’s kind of going on in the organization—at a level of detail that you're going to consume that information.” Now serving as Oracle’s vice president of product strategy and industry marketing, Mahmud shares his thoughts on how Oracle’s Primavera solutions have evolved and how best-in-class project portfolio management systems can help businesses stay competitive. Profit: What do you feel are the market dynamics that are changing project management today? Mahmud: First, the data explosion. We're generating data at twice the rate at which we can actually store it. The same concept applies for project-intensive organizations. A lot of data is gathered, but what are we really doing with it? Are we turning data into insight? Are we using that insight and turning it into foresight with analytics tools? This is a key driver that will separate the very good companies—the very competitive companies—from those that are not as competitive. Another trend is centered on the explosion of mobile computing. By the year 2013, an estimated 35 percent of the world’s workforce is going to be mobile. That’s one billion people. So the question is not if you're going to go mobile, it’s how fast you are going to go mobile. What kind of impact does that have on how the workforce participates in projects? What worked ten to fifteen years ago is not going to work today. It requires a real rethink around the interfaces and how data is actually presented. Profit: What is the role of project management in this new landscape? Mahmud: We recently conducted a PPM study with the Economist Intelligence Unit centered to determine how important project management is considered within organizations. Our target was primarily CFOs, CIOs, and senior managers and we discovered that while 95 percent of participants believed it critical to their business, only six percent were confident that projects were delivered on time and on budget. That’s a huge gap. Most organizations are looking for efficiency, especially in these volatile financial times. But senior management can’t keep track of every project in a large organization. As a result, executives are attempting to inventory the work being conducted under their watch. What is often needed is a very high-level assessment conducted at the board level to say, “Here are the 50 initiatives that we have underway. How do they line up with our strategic drivers?” This line of questioning can provide early warning that work and strategy are out of alignment; finding the gap between what the business needs to do and the actual performance scorecard. That’s low-hanging fruit for any executive looking to increase efficiency and save money. But it can only be obtained through proper assessment of existing projects—and you need a project system of record to get that done. Over the next decade or so, project management is going to transform into holistic work management. Business leaders will want make sure key projects align with corporate strategy, but also the ability to drill down into daily activity and smaller projects to make sure they line up as well. Keeping employees from working on tasks—even for a few hours—that don’t line up with corporate goals will, in many ways, become a competitive differentiator. Profit: How do all of these market challenges and shifting trends impact Oracle’s Primavera solutions and meeting customers’ needs? Mahmud: For Primavera, it’s a transformation from being a project management application to a PPM system in the enterprise. Also making that system a mission-critical application by connecting to other key applications within the ecosystem, such as the enterprise resource planning (ERP), supply chain, and CRM systems. Analytics have also become a huge component. Business analytics have made Oracle’s Primavera applications pertinent in the boardroom. Now, as a senior manager, a board member, a CXO, CIO, or CEO, you have direct visibility into what’s going on in the organization at a level that you're able to consume that information. In addition, all of this information pairs up really well with your financials and other data. Certainly, when you're an Oracle shop, you have that visibility that you didn’t have before from a project execution perspective. Profit: What new strategies and tools are being implemented to create a more efficient workplace for users? Mahmud: We believe very strongly that just because you call something an enterprise project portfolio management system doesn’t make it so—you have to get people to want to participate in the system. This can’t be mandated down from the top. It simply doesn’t work that way. A truly adoptable solution is one that makes it super easy for all types users to participate, by providing them interfaces where they live. Keeping that in mind, a major area of development has been alternative user interfaces. This is increasingly resulting in the creation of lighter weight, targeted interfaces such as iOS applications, and smartphones interfaces such as for iPhone and Android platform. Profit: How does this translate into the development of Oracle’s Primavera solutions? Mahmud: Let me give you a few examples. We recently announced the launch of our Primavera P6 Team Member application, which is a native iOS application for the iPhone. This interface makes it easier for team members to do their jobs quickly and effectively. Similarly, we introduced the Primavera analytics application, which can be consumed via mobile devices, and when married with Oracle Spatial capabilities, users can get a geographical view of what’s going on and which projects are occurring in various locations around the world. Lastly, we introduced advanced email integration that allows project team members to status work via E-mail. This functionality leverages the fact that users are in E-mail system throughout the day and allows them to status their work without the need to launch the Primavera application. It comes back to a mantra: provide as many alternative user interfaces as possible, so you can give people the ability to work, to participate, to raise issues, to create projects, in the places where they live. Do it in such a way that it’s non-intrusive, do it in such a way that it’s easy and intuitive and they can get it done in a short amount of time. If you do that, workers can get back to doing what they're actually getting paid for.

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  • Data Source Connection Pool Sizing

    - by Steve Felts
    Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* 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:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";} One of the most time-consuming procedures of a database application is establishing a connection. The connection pooling of the data source can be used to minimize this overhead.  That argues for using the data source instead of accessing the database driver directly. Configuring the size of the pool in the data source is somewhere between an art and science – this article will try to move it closer to science.  From the beginning, WLS data source has had an initial capacity and a maximum capacity configuration values.  When the system starts up and when it shrinks, initial capacity is used.  The pool can grow to maximum capacity.  Customers found that they might want to set the initial capacity to 0 (more on that later) but didn’t want the pool to shrink to 0.  In WLS 10.3.6, we added minimum capacity to specify the lower limit to which a pool will shrink.  If minimum capacity is not set, it defaults to the initial capacity for upward compatibility.   We also did some work on the shrinking in release 10.3.4 to reduce thrashing; the algorithm that used to shrink to the maximum of the currently used connections or the initial capacity (basically the unused connections were all released) was changed to shrink by half of the unused connections. The simple approach to sizing the pool is to set the initial/minimum capacity to the maximum capacity.  Doing this creates all connections at startup, avoiding creating connections on demand and the pool is stable.  However, there are a number of reasons not to take this simple approach. When WLS is booted, the deployment of the data source includes synchronously creating the connections.  The more connections that are configured in initial capacity, the longer the boot time for WLS (there have been several projects for parallel boot in WLS but none that are available).  Related to creating a lot of connections at boot time is the problem of logon storms (the database gets too much work at one time).   WLS has a solution for that by setting the login delay seconds on the pool but that also increases the boot time. There are a number of cases where it is desirable to set the initial capacity to 0.  By doing that, the overhead of creating connections is deferred out of the boot and the database doesn’t need to be available.  An application may not want WLS to automatically connect to the database until it is actually needed, such as for some code/warm failover configurations. There are a number of cases where minimum capacity should be less than maximum capacity.  Connections are generally expensive to keep around.  They cause state to be kept on both the client and the server, and the state on the backend may be heavy (for example, a process).  Depending on the vendor, connection usage may cost money.  If work load is not constant, then database connections can be freed up by shrinking the pool when connections are not in use.  When using Active GridLink, connections can be created as needed according to runtime load balancing (RLB) percentages instead of by connection load balancing (CLB) during data source deployment. Shrinking is an effective technique for clearing the pool when connections are not in use.  In addition to the obvious reason that there times where the workload is lighter,  there are some configurations where the database and/or firewall conspire to make long-unused or too-old connections no longer viable.  There are also some data source features where the connection has state and cannot be used again unless the state matches the request.  Examples of this are identity based pooling where the connection has a particular owner and XA affinity where the connection is associated with a particular RAC node.  At this point, WLS does not re-purpose (discard/replace) connections and shrinking is a way to get rid of the unused existing connection and get a new one with the correct state when needed. So far, the discussion has focused on the relationship of initial, minimum, and maximum capacity.  Computing the maximum size requires some knowledge about the application and the current number of simultaneously active users, web sessions, batch programs, or whatever access patterns are common.  The applications should be written to only reserve and close connections as needed but multiple statements, if needed, should be done in one reservation (don’t get/close more often than necessary).  This means that the size of the pool is likely to be significantly smaller then the number of users.   If possible, you can pick a size and see how it performs under simulated or real load.  There is a high-water mark statistic (ActiveConnectionsHighCount) that tracks the maximum connections concurrently used.  In general, you want the size to be big enough so that you never run out of connections but no bigger.   It will need to deal with spikes in usage, which is where shrinking after the spike is important.  Of course, the database capacity also has a big influence on the decision since it’s important not to overload the database machine.  Planning also needs to happen if you are running in a Multi-Data Source or Active GridLink configuration and expect that the remaining nodes will take over the connections when one of the nodes in the cluster goes down.  For XA affinity, additional headroom is also recommended.  In summary, setting initial and maximum capacity to be the same may be simple but there are many other factors that may be important in making the decision about sizing.

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  • trying to use mod_proxy with httpd and tomcat

    - by techsjs2012
    I been trying to use mod_proxy with httpd and tomcat... I have on VirtualBox running Scientific Linux which has httpd and tomcat 6 on it.. I made two nodes of tomcat6. I followed this guide like 10 times and still cant get the 2nd node of tomcat working.. http://www.richardnichols.net/2010/08/5-minute-guide-clustering-apache-tomcat/ Here is the lines from my http.conf file <Proxy balancer://testcluster stickysession=JSESSIONID> BalancerMember ajp://127.0.0.1:8009 min=10 max=100 route=node1 loadfactor=1 BalancerMember ajp://127.0.0.1:8109 min=10 max=100 route=node2 loadfactor=1 </Proxy> ProxyPass /examples balancer://testcluster/examples <Location /balancer-manager> SetHandler balancer-manager AuthType Basic AuthName "Balancer Manager" AuthUserFile "/etc/httpd/conf/.htpasswd" Require valid-user </Location> Now here is my server.xml from node1 <?xml version='1.0' encoding='utf-8'?> <!-- Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to You under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. --> <!-- Note: A "Server" is not itself a "Container", so you may not define subcomponents such as "Valves" at this level. Documentation at /docs/config/server.html --> <Server port="8005" shutdown="SHUTDOWN"> <!--APR library loader. Documentation at /docs/apr.html --> <Listener className="org.apache.catalina.core.AprLifecycleListener" SSLEngine="on" /> <!--Initialize Jasper prior to webapps are loaded. Documentation at /docs/jasper-howto.html --> <Listener className="org.apache.catalina.core.JasperListener" /> <!-- Prevent memory leaks due to use of particular java/javax APIs--> <Listener className="org.apache.catalina.core.JreMemoryLeakPreventionListener" /> <!-- JMX Support for the Tomcat server. Documentation at /docs/non-existent.html --> <Listener className="org.apache.catalina.mbeans.ServerLifecycleListener" /> <Listener className="org.apache.catalina.mbeans.GlobalResourcesLifecycleListener" /> <!-- Global JNDI resources Documentation at /docs/jndi-resources-howto.html --> <GlobalNamingResources> <!-- Editable user database that can also be used by UserDatabaseRealm to authenticate users --> <Resource name="UserDatabase" auth="Container" type="org.apache.catalina.UserDatabase" description="User database that can be updated and saved" factory="org.apache.catalina.users.MemoryUserDatabaseFactory" pathname="conf/tomcat-users.xml" /> </GlobalNamingResources> <!-- A "Service" is a collection of one or more "Connectors" that share a single "Container" Note: A "Service" is not itself a "Container", so you may not define subcomponents such as "Valves" at this level. Documentation at /docs/config/service.html --> <Service name="Catalina"> <!--The connectors can use a shared executor, you can define one or more named thread pools--> <!-- <Executor name="tomcatThreadPool" namePrefix="catalina-exec-" maxThreads="150" minSpareThreads="4"/> --> <!-- A "Connector" represents an endpoint by which requests are received and responses are returned. Documentation at : Java HTTP Connector: /docs/config/http.html (blocking & non-blocking) Java AJP Connector: /docs/config/ajp.html APR (HTTP/AJP) Connector: /docs/apr.html Define a non-SSL HTTP/1.1 Connector on port 8080 <Connector port="8080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8443" /> --> <!-- A "Connector" using the shared thread pool--> <!-- <Connector executor="tomcatThreadPool" port="8080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8443" /> --> <!-- Define a SSL HTTP/1.1 Connector on port 8443 This connector uses the JSSE configuration, when using APR, the connector should be using the OpenSSL style configuration described in the APR documentation --> <!-- <Connector port="8443" protocol="HTTP/1.1" SSLEnabled="true" maxThreads="150" scheme="https" secure="true" clientAuth="false" sslProtocol="TLS" /> --> <!-- Define an AJP 1.3 Connector on port 8009 --> <Connector port="8009" protocol="AJP/1.3" redirectPort="8443" /> <!-- An Engine represents the entry point (within Catalina) that processes every request. The Engine implementation for Tomcat stand alone analyzes the HTTP headers included with the request, and passes them on to the appropriate Host (virtual host). Documentation at /docs/config/engine.html --> <!-- You should set jvmRoute to support load-balancing via AJP ie : <Engine name="Catalina" defaultHost="localhost" jvmRoute="jvm1"> --> <Engine name="Catalina" defaultHost="localhost" jvmRoute="node1"> <!--For clustering, please take a look at documentation at: /docs/cluster-howto.html (simple how to) /docs/config/cluster.html (reference documentation) --> <!-- <Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster"/> --> <!-- The request dumper valve dumps useful debugging information about the request and response data received and sent by Tomcat. Documentation at: /docs/config/valve.html --> <!-- <Valve className="org.apache.catalina.valves.RequestDumperValve"/> --> <!-- This Realm uses the UserDatabase configured in the global JNDI resources under the key "UserDatabase". Any edits that are performed against this UserDatabase are immediately available for use by the Realm. --> <Realm className="org.apache.catalina.realm.UserDatabaseRealm" resourceName="UserDatabase"/> <!-- Define the default virtual host Note: XML Schema validation will not work with Xerces 2.2. --> <Host name="localhost" appBase="webapps" unpackWARs="true" autoDeploy="true" xmlValidation="false" xmlNamespaceAware="false"> <!-- SingleSignOn valve, share authentication between web applications Documentation at: /docs/config/valve.html --> <!-- <Valve className="org.apache.catalina.authenticator.SingleSignOn" /> --> <!-- Access log processes all example. Documentation at: /docs/config/valve.html --> <!-- <Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs" prefix="localhost_access_log." suffix=".txt" pattern="common" resolveHosts="false"/> --> </Host> </Engine> </Service> </Server> now here is the server.xml file from node2 <?xml version='1.0' encoding='utf-8'?> <!-- Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to You under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. --> <!-- Note: A "Server" is not itself a "Container", so you may not define subcomponents such as "Valves" at this level. Documentation at /docs/config/server.html --> <Server port="8105" shutdown="SHUTDOWN"> <!--APR library loader. Documentation at /docs/apr.html --> <Listener className="org.apache.catalina.core.AprLifecycleListener" SSLEngine="on" /> <!--Initialize Jasper prior to webapps are loaded. Documentation at /docs/jasper-howto.html --> <Listener className="org.apache.catalina.core.JasperListener" /> <!-- Prevent memory leaks due to use of particular java/javax APIs--> <Listener className="org.apache.catalina.core.JreMemoryLeakPreventionListener" /> <!-- JMX Support for the Tomcat server. Documentation at /docs/non-existent.html --> <Listener className="org.apache.catalina.mbeans.ServerLifecycleListener" /> <Listener className="org.apache.catalina.mbeans.GlobalResourcesLifecycleListener" /> <!-- Global JNDI resources Documentation at /docs/jndi-resources-howto.html --> <GlobalNamingResources> <!-- Editable user database that can also be used by UserDatabaseRealm to authenticate users --> <Resource name="UserDatabase" auth="Container" type="org.apache.catalina.UserDatabase" description="User database that can be updated and saved" factory="org.apache.catalina.users.MemoryUserDatabaseFactory" pathname="conf/tomcat-users.xml" /> </GlobalNamingResources> <!-- A "Service" is a collection of one or more "Connectors" that share a single "Container" Note: A "Service" is not itself a "Container", so you may not define subcomponents such as "Valves" at this level. Documentation at /docs/config/service.html --> <Service name="Catalina"> <!--The connectors can use a shared executor, you can define one or more named thread pools--> <!-- <Executor name="tomcatThreadPool" namePrefix="catalina-exec-" maxThreads="150" minSpareThreads="4"/> --> <!-- A "Connector" represents an endpoint by which requests are received and responses are returned. Documentation at : Java HTTP Connector: /docs/config/http.html (blocking & non-blocking) Java AJP Connector: /docs/config/ajp.html APR (HTTP/AJP) Connector: /docs/apr.html Define a non-SSL HTTP/1.1 Connector on port 8080 <Connector port="8080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8443" /> --> <!-- A "Connector" using the shared thread pool--> <!-- <Connector executor="tomcatThreadPool" port="8080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8443" /> --> <!-- Define a SSL HTTP/1.1 Connector on port 8443 This connector uses the JSSE configuration, when using APR, the connector should be using the OpenSSL style configuration described in the APR documentation --> <!-- <Connector port="8443" protocol="HTTP/1.1" SSLEnabled="true" maxThreads="150" scheme="https" secure="true" clientAuth="false" sslProtocol="TLS" /> --> <!-- Define an AJP 1.3 Connector on port 8009 --> <Connector port="8109" protocol="AJP/1.3" redirectPort="8443" /> <!-- An Engine represents the entry point (within Catalina) that processes every request. The Engine implementation for Tomcat stand alone analyzes the HTTP headers included with the request, and passes them on to the appropriate Host (virtual host). Documentation at /docs/config/engine.html --> <!-- You should set jvmRoute to support load-balancing via AJP ie : <Engine name="Catalina" defaultHost="localhost" jvmRoute="jvm1"> --> <Engine name="Catalina" defaultHost="localhost" jvmRoute="node2"> <!--For clustering, please take a look at documentation at: /docs/cluster-howto.html (simple how to) /docs/config/cluster.html (reference documentation) --> <!-- <Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster"/> --> <!-- The request dumper valve dumps useful debugging information about the request and response data received and sent by Tomcat. Documentation at: /docs/config/valve.html --> <!-- <Valve className="org.apache.catalina.valves.RequestDumperValve"/> --> <!-- This Realm uses the UserDatabase configured in the global JNDI resources under the key "UserDatabase". Any edits that are performed against this UserDatabase are immediately available for use by the Realm. --> <Realm className="org.apache.catalina.realm.UserDatabaseRealm" resourceName="UserDatabase"/> <!-- Define the default virtual host Note: XML Schema validation will not work with Xerces 2.2. --> <Host name="localhost" appBase="webapps" unpackWARs="true" autoDeploy="true" xmlValidation="false" xmlNamespaceAware="false"> <!-- SingleSignOn valve, share authentication between web applications Documentation at: /docs/config/valve.html --> <!-- <Valve className="org.apache.catalina.authenticator.SingleSignOn" /> --> <!-- Access log processes all example. Documentation at: /docs/config/valve.html --> <!-- <Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs" prefix="localhost_access_log." suffix=".txt" pattern="common" resolveHosts="false"/> --> </Host> </Engine> </Service> </Server> I dont know what it is. but I been trying for days

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  • Oracle performance problem

    - by jreid42
    We are using an Oracle 11G machine that is very powerful; has redundant storage etc. It's a beast from what I have been told. We just got this DB for a tool that when I first came on as a coop had like 20 people using, now its upwards of 150 people. I am the only one working on it :( We currently have a system in place that distributes PERL scripts across our entire data center essentially giving us a sort of "grid" computing power. The Perl scripts run a sort of simulation and report back the results to the database. They do selects / inserts. The load is not very high for each script but it could be happening across 20-50 systems at the same time. We then have multiple data centers and users all hitting the same database with this same approach. Our main problem with this is that our database is getting overloaded with connections and having to drop some. We sometimes have upwards of 500 connections. These are old perl scripts and they do not handle this well. Essentially they fail and the results are lost. I would rather avoid having to rewrite a lot of these as they are poorly written, and are a headache to even look at. The database itself is not overloaded, just the connection overhead is too high. We open a connection, make a quick query and then drop the connection. Very short connections but many of them. The database team has basically said we need to lower the number of connections or they are going to ignore us. Because this is distributed across our farm we cant implement persistent connections. I do this with our webserver; but its on a fixed system. The other ones are perl scripts that get opened and closed by the distribution tool and thus arent always running. What would be my best approach to resolving this issue? The scripts themselves can wait for a connection to be open. They do not need to act immediately. Some sort of queing system? I've been suggested to set up a few instances of a tool called "SQL Relay". Maybe one in each data center. How reliable is this tool? How good is this approach? Would it work for what we need? We could have one for each data center and relay requests through it to our main database, keeping a pipeline of open persistent connections? Does this make sense? Is there any other suggestions you can make? Any ideas? Any help would be greatly appreciated. Sadly I am just a coop student working for a very big company and somehow all of this has landed all on my shoulders (there is literally nobody to ask for help; its a hardware company, everybody is hardware engineers, and the database team is useless and in India) and I am quite lost as what the best approach would be? I am extremely overworked and this problem is interfering with on going progress and basically needs to be resolved as quickly as possible; preferably without rewriting the whole system, purchasing hardware (not gonna happen), or shooting myself in the foot. HELP LOL!

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  • What is the coolest thing you can do in <10 lines of simple code? Help me inspire beginners!

    - by Tom Ritter
    I'm looking for the coolest thing you can do in a few lines of simple code. I'm sure you can write a Mandelbrot set in Haskell in 15 lines but it's difficult to follow. My goal is to inspire students that programming is cool. We know that programming is cool because you can create anything you imagine - it's the ultimate creative outlet. I want to inspire these beginners and get them over as many early-learning humps as I can. Now, my reasons are selfish. I'm teaching an Intro to Computing course to a group of 60 half-engineering, half business majors; all freshmen. They are the students who came from underprivileged High schools. From my past experience, the group is generally split as follows: a few rock-stars, some who try very hard and kind of get it, the few who try very hard and barely get it, and the few who don't care. I want to reach as many of these groups as effectively as I can. Here's an example of how I'd use a computer program to teach: Here's an example of what I'm looking for: a 1-line VBS script to get your computer to talk to you: CreateObject("sapi.spvoice").Speak InputBox("Enter your text","Talk it") I could use this to demonstrate order of operations. I'd show the code, let them play with it, then explain that There's a lot going on in that line, but the computer can make sense of it, because it knows the rules. Then I'd show them something like this: 4(5*5) / 10 + 9(.25 + .75) And you can see that first I need to do is (5*5). Then I can multiply for 4. And now I've created the Object. Dividing by 10 is the same as calling Speak - I can't Speak before I have an object, and I can't divide before I have 100. Then on the other side I first create an InputBox with some instructions for how to display it. When I hit enter on the input box it evaluates or "returns" whatever I entered. (Hint: 'oooooo' makes a funny sound) So when I say Speak, the right side is what to Speak. And I get that from the InputBox. So when you do several things on a line, like: x = 14 + y; You need to be aware of the order of things. First we add 14 and y. Then we put the result (what it evaluates to, or returns) into x. That's my goal, to have a bunch of these cool examples to demonstrate and teach the class while they have fun. I tried this example on my roommate and while I may not use this as the first lesson, she liked it and learned something. Some cool mathematica programs that make beautiful graphs or shapes that are easy to understand would be good ideas and I'm going to look into those. Here are some complicated actionscript examples but that's a bit too advanced and I can't teach flash. What other ideas do you have?

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  • Is SHA-1 secure for password storage?

    - by Tgr
    Some people throw around remarks like "SHA-1 is broken" a lot, so I'm trying to understand what exactly that means. Let's assume I have a database of SHA-1 password hashes, and an attacker whith a state of the art SHA-1 breaking algorithm and a botnet with 100,000 machines gets access to it. (Having control over 100k home computers would mean they can do about 10^15 operations per second.) How much time would they need to find out the password of any one user? find out the password of a given user? find out the password of all users? find a way to log in as one of the users? find a way to log in as a specific user? How does that change if the passwords are salted? Does the method of salting (prefix, postfix, both, or something more complicated like xor-ing) matter? Here is my current understanding, after some googling. Please correct in the answers if I misunderstood something. If there is no salt, a rainbow attack will immediately find all passwords (except extremely long ones). If there is a sufficiently long random salt, the most effective way to find out the passwords is a brute force or dictionary attack. Neither collision nor preimage attacks are any help in finding out the actual password, so cryptographic attacks against SHA-1 are no help here. It doesn't even matter much what algorithm is used - one could even use MD5 or MD4 and the passwords would be just as safe (there is a slight difference because computing a SHA-1 hash is slower). To evaluate how safe "just as safe" is, let's assume that a single sha1 run takes 1000 operations and passwords contain uppercase, lowercase and digits (that is, 60 characters). That means the attacker can test 1015*60*60*24 / 1000 ~= 1017 potential password a day. For a brute force attack, that would mean testing all passwords up to 9 characters in 3 hours, up to 10 characters in a week, up to 11 characters in a year. (It takes 60 times as much for every additional character.) A dictionary attack is much, much faster (even an attacker with a single computer could pull it off in hours), but only finds weak passwords. To log in as a user, the attacker does not need to find out the exact password; it is enough to find a string that results in the same hash. This is called a first preimage attack. As far as I could find, there are no preimage attacks against SHA-1. (A bruteforce attack would take 2160 operations, which means our theoretical attacker would need 1030 years to pull it off. Limits of theoretical possibility are around 260 operations, at which the attack would take a few years.) There are preimage attacks against reduced versions of SHA-1 with negligible effect (for the reduced SHA-1 which uses 44 steps instead of 80, attack time is down from 2160 operations to 2157). There are collision attacks against SHA-1 which are well within theoretical possibility (the best I found brings the time down from 280 to 252), but those are useless against password hashes, even without salting. In short, storing passwords with SHA-1 seems perfectly safe. Did I miss something?

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  • Can the STREAM and GUPS (single CPU) benchmark use non-local memory in NUMA machine

    - by osgx
    Hello I want to run some tests from HPCC, STREAM and GUPS. They will test memory bandwidth, latency, and throughput (in term of random accesses). Can I start Single CPU test STREAM or Single CPU GUPS on NUMA node with memory interleaving enabled? (Is it allowed by the rules of HPCC - High Performance Computing Challenge?) Usage of non-local memory can increase GUPS results, because it will increase 2- or 4- fold the number of memory banks, available for random accesses. (GUPS typically limited by nonideal memory-subsystem and by slow memory bank opening/closing. With more banks it can do update to one bank, while the other banks are opening/closing.) Thanks. UPDATE: (you may nor reorder the memory accesses that the program makes). But can compiler reorder loops nesting? E.g. hpcc/RandomAccess.c /* Perform updates to main table. The scalar equivalent is: * * u64Int ran; * ran = 1; * for (i=0; i<NUPDATE; i++) { * ran = (ran << 1) ^ (((s64Int) ran < 0) ? POLY : 0); * table[ran & (TableSize-1)] ^= stable[ran >> (64-LSTSIZE)]; * } */ for (j=0; j<128; j++) ran[j] = starts ((NUPDATE/128) * j); for (i=0; i<NUPDATE/128; i++) { /* #pragma ivdep */ for (j=0; j<128; j++) { ran[j] = (ran[j] << 1) ^ ((s64Int) ran[j] < 0 ? POLY : 0); Table[ran[j] & (TableSize-1)] ^= stable[ran[j] >> (64-LSTSIZE)]; } } The main loop here is for (i=0; i<NUPDATE/128; i++) { and the nested loop is for (j=0; j<128; j++) {. Using 'loop interchange' optimization, compiler can convert this code to for (j=0; j<128; j++) { for (i=0; i<NUPDATE/128; i++) { ran[j] = (ran[j] << 1) ^ ((s64Int) ran[j] < 0 ? POLY : 0); Table[ran[j] & (TableSize-1)] ^= stable[ran[j] >> (64-LSTSIZE)]; } } It can be done because this loop nest is perfect loop nest. Is such optimization prohibited by rules of HPCC?

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  • Is it possible to implement bitwise operators using integer arithmetic?

    - by Statement
    Hello World! I am facing a rather peculiar problem. I am working on a compiler for an architecture that doesn't support bitwise operations. However, it handles signed 16 bit integer arithmetics and I was wondering if it would be possible to implement bitwise operations using only: Addition (c = a + b) Subtraction (c = a - b) Division (c = a / b) Multiplication (c = a * b) Modulus (c = a % b) Minimum (c = min(a, b)) Maximum (c = max(a, b)) Comparisons (c = (a < b), c = (a == b), c = (a <= b), et.c.) Jumps (goto, for, et.c.) The bitwise operations I want to be able to support are: Or (c = a | b) And (c = a & b) Xor (c = a ^ b) Left Shift (c = a << b) Right Shift (c = a b) (All integers are signed so this is a problem) Signed Shift (c = a b) One's Complement (a = ~b) (Already found a solution, see below) Normally the problem is the other way around; how to achieve arithmetic optimizations using bitwise hacks. However not in this case. Writable memory is very scarce on this architecture, hence the need for bitwise operations. The bitwise functions themselves should not use a lot of temporary variables. However, constant read-only data & instruction memory is abundant. A side note here also is that jumps and branches are not expensive and all data is readily cached. Jumps cost half the cycles as arithmetic (including load/store) instructions do. On other words, all of the above supported functions cost twice the cycles of a single jump. Some thoughts that might help: I figured out that you can do one's complement (negate bits) with the following code: // Bitwise one's complement b = ~a; // Arithmetic one's complement b = -1 - a; I also remember the old shift hack when dividing with a power of two so the bitwise shift can be expressed as: // Bitwise left shift b = a << 4; // Arithmetic left shift b = a * 16; // 2^4 = 16 // Signed right shift b = a >>> 4; // Arithmetic right shift b = a / 16; For the rest of the bitwise operations I am slightly clueless. I wish the architects of this architecture would have supplied bit-operations. I would also like to know if there is a fast/easy way of computing the power of two (for shift operations) without using a memory data table. A naive solution would be to jump into a field of multiplications: b = 1; switch (a) { case 15: b = b * 2; case 14: b = b * 2; // ... exploting fallthrough (instruction memory is magnitudes larger) case 2: b = b * 2; case 1: b = b * 2; } Or a Set & Jump approach: switch (a) { case 15: b = 32768; break; case 14: b = 16384; break; // ... exploiting the fact that a jump is faster than one additional mul // at the cost of doubling the instruction memory footprint. case 2: b = 4; break; case 1: b = 2; break; }

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  • Var null and not an object when using document.getElementById

    - by Dean
    Hi, I'm doing some work in HTML and JQuery. I have a problem of my textarea and submit button not appearing after the radio button is selected. My HTML looks like this: <html> <head><title>Publications Database | Which spotlight for Publications</title> <script type="text/javascript" src="./jquery.js"></script> <script src="./addSpotlight.js" type="text/javascript" charset="utf-8"></script> </head> <body> <div class="wrapper"> <div class="header"> <div class="headerText">Which spotlight for Publications</div> </div> <div class="mainContent"> <p>Please select the publication that you would like to make the spotlight of this month:</p> <form action="addSpotlight" method="POST" id="form" name="form"> <div class="div29" id="div29"><input type="radio" value="29" name="publicationIDs" >A System For Dynamic Server Allocation in Application Server Clusters, IEEE International Symposium on Parallel and Distributed Processsing with Applications, 2008 </div> <div class="div30" id="div30"><input type="radio" value="30" name="publicationIDs" >Analysing BitTorrent's Seeding Strategies, 7th IEEE/IFIP International Conference on Embedded and Ubiquitous Computing (EUC-09), 2009 </div> <div class="div31" id="div31"><input type="radio" value="31" name="publicationIDs" >The Effect of Server Reallocation Time in Dynamic Resource Allocation, UK Performance Engineering Workshop 2009, 2009 </div> <div class="div32" id="div32"><input type="radio" value="32" name="publicationIDs" >idk, hello, 1992 </div> <div class="div33" id="div33"><input type="radio" value="33" name="publicationIDs" >sad, safg, 1992 </div> <div class="abstractWriteup" id="abstractWriteup"><textarea name="abstract"></textarea> <input type="submit" value="Add Spotlight"></div> </form> </div> </div> </body> </html> My javascript looks like this: $(document).ready( function() { $('.abstractWriteup').hide(); addAbstract(); }); function addAbstract() { var abstractWU = document.getElementById('.abstractWriteup'); $("input[name='publicationIDs']").change(function() { var abstractWU = document.getElementById('.abstractWriteup'); var classNameOfSelected = $("input[name='publicationIDs']").val(); var radioSelected = document.getElementById("div"+classNameOfSelected); var parentDiv = radioSelected.parentNode; parentDiv.insertBefore(radioSelected, abstractWU.nextSibling); $('.abstractWriteup').show(); });}; I have developed this by using Node#insertBefore. When I have had it working it has been rearranging the radio buttons. Thanks in Advance Dean

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  • Custom Online Backup Solution Advice

    - by Martín Marconcini
    I have to implement a way so our customers can backup their SQL 2000/5/8 databasase online. The application they use is a C#/.NET35 Winforms application that connects to a SQL Server (can be 2000/2005/2008, sometimes express editions). The SQL Server is on the same LAN. Our application has a very specific UI and we must code each form following those guidelines. There’s lots of GDI+ to give it the look and feel we want. For that reason, using a 3rd party application is not a very good idea. We need to charge the customer on a monthly/annual basis for the service. Preferably, the customer doesn’t need to care about bandwidth and storage space. It must be transparent. Given the above reqs., my first thoughts are: Solution 1: Code some sort of FTP basic functionality with behind the scenes SQL Backup mechanism, then hire a Hosting service and compress-transfer the .BAK to the Hosting. Maintain a series of Folders (for each customer). They won’t see what’s happening. They will just see a list of their files and a big “Backup now” button that will perform the SQL backup, compress it and upload it (and update the file list) ;) Pros: Not very complicated to implement, simple to use, fairly simple to configure (could have a dedicated ftp user/pass) Cons: Finding a “ftp” only hosting plan is not probably going to be easy, they usually come with a bunch of stuff. FTP is not always the best protocol. more? Solution 2: Similar to 1, but instead of FTP, find a cloud computing service like Amazon S3, Mosso or similar. Pros: Cloud Storage is fast, reliable, etc. It’s kind of easy to implement (specially if there are APIs like AWS or Mosso). Cons: I have been unable to come up with a service optimized for resellers where I can give multiple sub-accounts (one for each customer). Billing is going to be a nightmare cuz these services bill per/GB and with One account it’s impossible to differentiate each customer. Solution 3: Similar to 2, but letting the user create their own account on Amazon S3 (for example). Pros: You forget about billing and such. Cons: A mess for the customer who has to open the Amazon (or whatever) account, will be charged for that and not from you. You can’t really charge the customer (since you’re just not doing anything). Solution 4: Use one of the many backup online solutions that use the tech in cloud storage. Pros: many of these include SQL Server backup, and a lot of features that we’d have to implement. Plus web access and stuff like that will come included. Cons: Still have the billing problem described in number 2. Little of these companies (if any) offers “reseller” accounts. You have to eventually use their software (some offer certain branding). Any better approach? Summary: You have a software (.NET Winapp). You want your users to be able to backup their SQL Server databases online (and be able to retrieve the backups if needed). You ideally would like to charge the customer for this service (i.e. XX € a year).

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  • What version-control system is most trivial to set up and use for toy projects?

    - by Norman Ramsey
    I teach the third required intro course in a CS department. One of my homework assignments asks students to speed up code they have written for a previous assignment. Factor-of-ten speedups are routine; factors of 100 or 1000 are not unheard of. (For a factor of 1000 speedup you have to have made rookie mistakes with malloc().) Programs are improved by a sequence is small changes. I ask students to record and describe each change and the resulting improvement. While you're improving a program it is also possible to break it. Wouldn't it be nice to back out? You can see where I'm going with this: my students would benefit enormously from version control. But there are some caveats: Our computing environment is locked down. Anything that depends on a central repository is suspect. Our students are incredibly overloaded. Not just classes but jobs, sports, music, you name it. For them to use a new tool it has to be incredibly easy and have obvious benefits. Our students do most work in pairs. Getting bits back and forth between accounts is problematic. Could this problem also be solved by distributed version control? Complexity is the enemy. I know setting up a CVS repository is too baffling---I myself still have trouble because I only do it once a year. I'm told SVN is even harder. Here are my comments on existing systems: I think central version control (CVS or SVN) is ruled out because our students don't have the administrative privileges needed to make a repository that they can share with one other student. (We are stuck with Unix file permissions.) Also, setup on CVS or SVN is too hard. darcs is way easy to set up, but it's not obvious how you share things. darcs send (to send patches by email) seems promising but it's not clear how to set it up. The introductory documentation for git is not for beginners. Like CVS setup, it's something I myself have trouble with. I'm soliciting suggestions for what source-control to use with beginning students. I suspect we can find resources to put a thin veneer over an existing system and to simplify existing documentation. We probably don't have resources to write new documentation. So, what's really easy to setup, commit, revert, and share changes with a partner but does not have to be easy to merge or to work at scale? A key constraint is that programming pairs have to be able to share work with each other and only each other, and pairs change every week. Our infrastructure is Linux, Solaris, and Windows with a netapp filer. I doubt my IT staff wants to create a Unix group for each pair of students. Is there an easier solution I've overlooked? (Thanks for the accepted answer, which beats the others on account of its excellent reference to Git Magic as well as the helpful comments.)

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  • Binary operator overloading on a templated class (C++)

    - by GRB
    Hi all, I was recently trying to gauge my operator overloading/template abilities and as a small test, created the Container class below. While this code compiles fine and works correctly under MSVC 2008 (displays 11), both MinGW/GCC and Comeau choke on the operator+ overload. As I trust them more than MSVC, I'm trying to figure out what I'm doing wrong. Here is the code: #include <iostream> using namespace std; template <typename T> class Container { friend Container<T> operator+ <> (Container<T>& lhs, Container<T>& rhs); public: void setobj(T ob); T getobj(); private: T obj; }; template <typename T> void Container<T>::setobj(T ob) { obj = ob; } template <typename T> T Container<T>::getobj() { return obj; } template <typename T> Container<T> operator+ <> (Container<T>& lhs, Container<T>& rhs) { Container<T> temp; temp.obj = lhs.obj + rhs.obj; return temp; } int main() { Container<int> a, b; a.setobj(5); b.setobj(6); Container<int> c = a + b; cout << c.getobj() << endl; return 0; } This is the error Comeau gives: Comeau C/C++ 4.3.10.1 (Oct 6 2008 11:28:09) for ONLINE_EVALUATION_BETA2 Copyright 1988-2008 Comeau Computing. All rights reserved. MODE:strict errors C++ C++0x_extensions "ComeauTest.c", line 27: error: an explicit template argument list is not allowed on this declaration Container<T> operator+ <> (Container<T>& lhs, Container<T>& rhs) ^ 1 error detected in the compilation of "ComeauTest.c". I'm having a hard time trying to get Comeau/MingGW to play ball, so that's where I turn to you guys. It's been a long time since my brain has melted this much under the weight of C++ syntax, so I feel a little embarrassed ;). Thanks in advance. EDIT: Eliminated an (irrelevant) lvalue error listed in initial Comeau dump.

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  • How to Upgrade Your Netbook to Windows 7 Home Premium

    - by Matthew Guay
    Would you like more features and flash in Windows on your netbook?  Here’s how you can easily upgrade your netbook to Windows 7 Home Premium the easy way. Most new netbooks today ship with Windows 7 Starter, which is the cheapest edition of Windows 7.  It is fine for many computing tasks, and will run all your favorite programs great, but it lacks many customization, multimedia, and business features found in higher editions.  Here we’ll show you how you can quickly upgrade your netbook to more full-featured edition of Windows 7 using Windows Anytime Upgrade.  Also, if you want to upgrade your laptop or desktop to another edition of Windows 7, say Professional, you can follow these same steps to upgrade it, too. Please note: This is only for computers already running Windows 7.  If your netbook is running XP or Vista, you will have to run a traditional upgrade to install Windows 7. Upgrade Advisor First, let’s make sure your netbook can support the extra features, such as Aero Glass, in Windows 7 Home Premium.  Most modern netbooks that ship with Windows 7 Starter can run the advanced features in Windows 7 Home Premium, but let’s check just in case.  Download the Windows 7 Upgrade Advisor (link below), and install as normal. Once it’s installed, run it and click Start Check.   Make sure you’re connected to the internet before you run the check, or otherwise you may see this error message.  If you see it, click Ok and then connect to the internet and start the check again. It will now scan all of your programs and hardware to make sure they’re compatible with Windows 7.  Since you’re already running Windows 7 Starter, it will also tell you if your computer will support the features in other editions of Windows 7. After a few moments, the Upgrade Advisor will show you want it found.  Here we see that our netbook, a Samsung N150, can be upgraded to Windows 7 Home Premium, Professional, or Ultimate. We also see that we had one issue, but this was because a driver we had installed was not recognized.  Click “See all system requirements” to see what your netbook can do with the new edition. This shows you which of the requirements, including support for Windows Aero, your netbook meets.  Here our netbook supports Aero, so we’re ready to go upgrade. For more, check out our article on how to make sure your computer can run Windows 7 with Upgrade Advisor. Upgrade with Anytime Upgrade Now, we’re ready to upgrade our netbook to Windows 7 Home Premium.  Enter “Anytime Upgrade” in the Start menu search,and select Windows Anytime Upgrade. Windows Anytime Upgrade lets you upgrade using product key you already have or one you purchase during the upgrade process.  And, it installs without any downloads or Windows disks, so it works great even for netbooks without DVD drives. Anytime Upgrades are cheaper than a standard upgrade, and for a limited time, select retailers in the US are offering Anytime Upgrades to Windows 7 Home Premium for only $49.99 if purchased with a new netbook.  If you already have a netbook running Windows 7 Starter, you can either purchase an Anytime Upgrade package at a retail store or purchase a key online during the upgrade process for $79.95.  Or, if you have a standard Windows 7 product key (full or upgrade), you can use it in Anytime upgrade.  This is especially nice if you can purchase Windows 7 cheaper through your school, university, or office. Purchase an upgrade online To purchase an upgrade online, click “Go online to choose the edition of Windows 7 that’s best for you”.   Here you can see a comparison of the features of each edition of Windows 7.  Note that you can upgrade to either Home Premium, Professional, or Ultimate.  We chose home Premium because it has most of the features that home users want, including Media Center and Aero Glass effects.  Also note that the price of each upgrade is cheaper than the respective upgrade from Windows XP or Vista.  Click buy under the edition you want.   Enter your billing information, then your payment information.  Once you confirm your purchase, you will directly be taken to the Upgrade screen.  Make sure to save your receipt, as you will need the product key if you ever need to reinstall Windows on your computer. Upgrade with an existing product key If you purchased an Anytime Upgrade kit from a retailer, or already have a Full or Upgrade key for another edition of Windows 7, choose “Enter an upgrade key”. Enter your product key, and click Next.  If you purchased an Anytime Upgrade kit, the product key will be located on the inside of the case on a yellow sticker. The key will be verified as a valid key, and Anytime Upgrade will automatically choose the correct edition of Windows 7 based on your product key.  Click Next when this is finished. Continuing the Upgrade process Whether you entered a key or purchased a key online, the process is the same from here on.  Click “I accept” to accept the license agreement. Now, you’re ready to install your upgrade.  Make sure to save all open files and close any programs, and then click Upgrade. The upgrade only takes about 10 minutes in our experience but your mileage may vary.  Any available Microsoft updates, including ones for Office, Security Essentials, and other products, will be installed before the upgrade takes place. After a couple minutes, your computer will automatically reboot and finish the installation.  It will then reboot once more, and your computer will be ready to use!  Welcome to your new edition of Windows 7! Here’s a before and after shot of our desktop.  When you do an Anytime Upgrade, all of your programs, files, and settings will be just as they were before you upgraded.  The only change we noticed was that our pinned taskbar icons were slightly rearranged to the default order of Internet Explorer, Explorer, and Media Player.  Here’s a shot of our desktop before the upgrade.  Notice that all of our pinned programs and desktop icons are still there, as well as our taskbar customization (we are using small icons on the taskbar instead of the default large icons). Before, with the Windows 7 Starter background and the Aero Basic theme: And after, with Aero Glass and the more colorful default Windows 7 background.   All of the features of Windows 7 Home Premium are now ready to use.  The Aero theme was activate by default, but you can now customize your netbook theme, background, and more with the Personalization pane.  To open it, right-click on your desktop and select Personalize. You can also now use Windows Media Center, and can play-back DVD movies using an external drive. One of our favorite tools, the Snipping Tool, is also now available for easy screenshots and clips. Activating you new edition of Windows 7 You will still need to activate your new edition of Windows 7.  To do this right away, open the start menu, right-click on Computer, and select Properties.   Scroll to the bottom, and click “Activate Windows Now”. Make sure you’re connected to the internet, and then select “Activate Windows online now”. Activation may take a few minutes, depending on your internet connection speed. When it is done, the Activation wizard will let you know that Windows is activated and genuine.  Your upgrade is all finished! Conclusion Windows Anytime Upgrade makes it easy, and somewhat cheaper, to upgrade to another edition of Windows 7.  It’s useful for desktop and laptop owners who want to upgrade to Professional or Ultimate, but many more netbook owners will want to upgrade from Starter to Home Premium or another edition.  Links Download the Windows 7 Upgrade Advisor Windows Team Blog: Anytime Upgrade Special with new PC purchase Similar Articles Productive Geek Tips How To Upgrade from Vista to Windows 7 Home Premium EditionAnother Blog You Should Subscribe ToMysticgeek Blog: Turn Vista Home Premium Into Ultimate (Part 3) – Shadow CopyUpgrade Ubuntu from Breezy to DapperHow to Upgrade the Windows 7 RC to RTM (Final Release) 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 DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Get Your Delicious Bookmarks In Firefox’s Awesome Bar Manage Photos Across Different Social Sites With Dropico Test Drive Windows 7 Online Download Wallpapers From National Geographic Site Spyware Blaster v4.3 Yes, it’s Patch Tuesday

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  • SQL SERVER – Guest Post – Jonathan Kehayias – Wait Type – Day 16 of 28

    - by pinaldave
    Jonathan Kehayias (Blog | Twitter) is a MCITP Database Administrator and Developer, who got started in SQL Server in 2004 as a database developer and report writer in the natural gas industry. After spending two and a half years working in TSQL, in late 2006, he transitioned to the role of SQL Database Administrator. His primary passion is performance tuning, where he frequently rewrites queries for better performance and performs in depth analysis of index implementation and usage. Jonathan blogs regularly on SQLBlog, and was a coauthor of Professional SQL Server 2008 Internals and Troubleshooting. On a personal note, I think Jonathan is extremely positive person. In every conversation with him I have found that he is always eager to help and encourage. Every time he finds something needs to be approved, he has contacted me without hesitation and guided me to improve, change and learn. During all the time, he has not lost his focus to help larger community. I am honored that he has accepted to provide his views on complex subject of Wait Types and Queues. Currently I am reading his series on Extended Events. Here is the guest blog post by Jonathan: SQL Server troubleshooting is all about correlating related pieces of information together to indentify where exactly the root cause of a problem lies. In my daily work as a DBA, I generally get phone calls like, “So and so application is slow, what’s wrong with the SQL Server.” One of the funny things about the letters DBA is that they go so well with Default Blame Acceptor, and I really wish that I knew exactly who the first person was that pointed that out to me, because it really fits at times. A lot of times when I get this call, the problem isn’t related to SQL Server at all, but every now and then in my initial quick checks, something pops up that makes me start looking at things further. The SQL Server is slow, we see a number of tasks waiting on ASYNC_IO_COMPLETION, IO_COMPLETION, or PAGEIOLATCH_* waits in sys.dm_exec_requests and sys.dm_exec_waiting_tasks. These are also some of the highest wait types in sys.dm_os_wait_stats for the server, so it would appear that we have a disk I/O bottleneck on the machine. A quick check of sys.dm_io_virtual_file_stats() and tempdb shows a high write stall rate, while our user databases show high read stall rates on the data files. A quick check of some performance counters and Page Life Expectancy on the server is bouncing up and down in the 50-150 range, the Free Page counter consistently hits zero, and the Free List Stalls/sec counter keeps jumping over 10, but Buffer Cache Hit Ratio is 98-99%. Where exactly is the problem? In this case, which happens to be based on a real scenario I faced a few years back, the problem may not be a disk bottleneck at all; it may very well be a memory pressure issue on the server. A quick check of the system spec’s and it is a dual duo core server with 8GB RAM running SQL Server 2005 SP1 x64 on Windows Server 2003 R2 x64. Max Server memory is configured at 6GB and we think that this should be enough to handle the workload; or is it? This is a unique scenario because there are a couple of things happening inside of this system, and they all relate to what the root cause of the performance problem is on the system. If we were to query sys.dm_exec_query_stats for the TOP 10 queries, by max_physical_reads, max_logical_reads, and max_worker_time, we may be able to find some queries that were using excessive I/O and possibly CPU against the system in their worst single execution. We can also CROSS APPLY to sys.dm_exec_sql_text() and see the statement text, and also CROSS APPLY sys.dm_exec_query_plan() to get the execution plan stored in cache. Ok, quick check, the plans are pretty big, I see some large index seeks, that estimate 2.8GB of data movement between operators, but everything looks like it is optimized the best it can be. Nothing really stands out in the code, and the indexing looks correct, and I should have enough memory to handle this in cache, so it must be a disk I/O problem right? Not exactly! If we were to look at how much memory the plan cache is taking by querying sys.dm_os_memory_clerks for the CACHESTORE_SQLCP and CACHESTORE_OBJCP clerks we might be surprised at what we find. In SQL Server 2005 RTM and SP1, the plan cache was allowed to take up to 75% of the memory under 8GB. I’ll give you a second to go back and read that again. Yes, you read it correctly, it says 75% of the memory under 8GB, but you don’t have to take my word for it, you can validate this by reading Changes in Caching Behavior between SQL Server 2000, SQL Server 2005 RTM and SQL Server 2005 SP2. In this scenario the application uses an entirely adhoc workload against SQL Server and this leads to plan cache bloat, and up to 4.5GB of our 6GB of memory for SQL can be consumed by the plan cache in SQL Server 2005 SP1. This in turn reduces the size of the buffer cache to just 1.5GB, causing our 2.8GB of data movement in this expensive plan to cause complete flushing of the buffer cache, not just once initially, but then another time during the queries execution, resulting in excessive physical I/O from disk. Keep in mind that this is not the only query executing at the time this occurs. Remember the output of sys.dm_io_virtual_file_stats() showed high read stalls on the data files for our user databases versus higher write stalls for tempdb? The memory pressure is also forcing heavier use of tempdb to handle sorting and hashing in the environment as well. The real clue here is the Memory counters for the instance; Page Life Expectancy, Free List Pages, and Free List Stalls/sec. The fact that Page Life Expectancy is fluctuating between 50 and 150 constantly is a sign that the buffer cache is experiencing constant churn of data, once every minute to two and a half minutes. If you add to the Page Life Expectancy counter, the consistent bottoming out of Free List Pages along with Free List Stalls/sec consistently spiking over 10, and you have the perfect memory pressure scenario. All of sudden it may not be that our disk subsystem is the problem, but is instead an innocent bystander and victim. Side Note: The Page Life Expectancy counter dropping briefly and then returning to normal operating values intermittently is not necessarily a sign that the server is under memory pressure. The Books Online and a number of other references will tell you that this counter should remain on average above 300 which is the time in seconds a page will remain in cache before being flushed or aged out. This number, which equates to just five minutes, is incredibly low for modern systems and most published documents pre-date the predominance of 64 bit computing and easy availability to larger amounts of memory in SQL Servers. As food for thought, consider that my personal laptop has more memory in it than most SQL Servers did at the time those numbers were posted. I would argue that today, a system churning the buffer cache every five minutes is in need of some serious tuning or a hardware upgrade. Back to our problem and its investigation: There are two things really wrong with this server; first the plan cache is excessively consuming memory and bloated in size and we need to look at that and second we need to evaluate upgrading the memory to accommodate the workload being performed. In the case of the server I was working on there were a lot of single use plans found in sys.dm_exec_cached_plans (where usecounts=1). Single use plans waste space in the plan cache, especially when they are adhoc plans for statements that had concatenated filter criteria that is not likely to reoccur with any frequency.  SQL Server 2005 doesn’t natively have a way to evict a single plan from cache like SQL Server 2008 does, but MVP Kalen Delaney, showed a hack to evict a single plan by creating a plan guide for the statement and then dropping that plan guide in her blog post Geek City: Clearing a Single Plan from Cache. We could put that hack in place in a job to automate cleaning out all the single use plans periodically, minimizing the size of the plan cache, but a better solution would be to fix the application so that it uses proper parameterized calls to the database. You didn’t write the app, and you can’t change its design? Ok, well you could try to force parameterization to occur by creating and keeping plan guides in place, or we can try forcing parameterization at the database level by using ALTER DATABASE <dbname> SET PARAMETERIZATION FORCED and that might help. If neither of these help, we could periodically dump the plan cache for that database, as discussed as being a problem in Kalen’s blog post referenced above; not an ideal scenario. The other option is to increase the memory on the server to 16GB or 32GB, if the hardware allows it, which will increase the size of the plan cache as well as the buffer cache. In SQL Server 2005 SP1, on a system with 16GB of memory, if we set max server memory to 14GB the plan cache could use at most 9GB  [(8GB*.75)+(6GB*.5)=(6+3)=9GB], leaving 5GB for the buffer cache.  If we went to 32GB of memory and set max server memory to 28GB, the plan cache could use at most 16GB [(8*.75)+(20*.5)=(6+10)=16GB], leaving 12GB for the buffer cache. Thankfully we have SQL Server 2005 Service Pack 2, 3, and 4 these days which include the changes in plan cache sizing discussed in the Changes to Caching Behavior between SQL Server 2000, SQL Server 2005 RTM and SQL Server 2005 SP2 blog post. In real life, when I was troubleshooting this problem, I spent a week trying to chase down the cause of the disk I/O bottleneck with our Server Admin and SAN Admin, and there wasn’t much that could be done immediately there, so I finally asked if we could increase the memory on the server to 16GB, which did fix the problem. It wasn’t until I had this same problem occur on another system that I actually figured out how to really troubleshoot this down to the root cause.  I couldn’t believe the size of the plan cache on the server with 16GB of memory when I actually learned about this and went back to look at it. SQL Server is constantly telling a story to anyone that will listen. As the DBA, you have to sit back and listen to all that it’s telling you and then evaluate the big picture and how all the data you can gather from SQL about performance relate to each other. One of the greatest tools out there is actually a free in the form of Diagnostic Scripts for SQL Server 2005 and 2008, created by MVP Glenn Alan Berry. Glenn’s scripts collect a majority of the information that SQL has to offer for rapid troubleshooting of problems, and he includes a lot of notes about what the outputs of each individual query might be telling you. When I read Pinal’s blog post SQL SERVER – ASYNC_IO_COMPLETION – Wait Type – Day 11 of 28, I noticed that he referenced Checking Memory Related Performance Counters in his post, but there was no real explanation about why checking memory counters is so important when looking at an I/O related wait type. I thought I’d chat with him briefly on Google Talk/Twitter DM and point this out, and offer a couple of other points I noted, so that he could add the information to his blog post if he found it useful.  Instead he asked that I write a guest blog for this. I am honored to be a guest blogger, and to be able to share this kind of information with the community. The information contained in this blog post is a glimpse at how I do troubleshooting almost every day of the week in my own environment. SQL Server provides us with a lot of information about how it is running, and where it may be having problems, it is up to us to play detective and find out how all that information comes together to tell us what’s really the problem. This blog post is written by Jonathan Kehayias (Blog | Twitter). Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: MVP, Pinal Dave, PostADay, Readers Contribution, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQL Wait Stats, SQL Wait Types, T SQL, Technology

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  • CodePlex Daily Summary for Thursday, April 29, 2010

    CodePlex Daily Summary for Thursday, April 29, 2010New ProjectsDesign Technology Laboratory: DTL project is prominent.Em-Lib: Electronic Music Library เป็นโปรแกรมที่พัฒนาขึ้นเพื่อให้เป็นห้องสมุดอิเล็กทรอนิกส์ โดยตัวโปรแกรมจะสามารถจำลองเครื่องดนตรี พร้อมข้อมูลที่เกี่ย...Extensions For ASP.NET: Extensions For ASP.NETFIM 2010 PowerShell Cmdlets: These PowerShell cmdlets let you manage objects in the Forefront Identity Manager 2010 web service easily and concisely. The five cmdlets let you e...Grunty OS: Grunty OS is a Free open source OS made my GruntXproductionsIrishDevelopers.net Test: IrishDevelopers.net TestJobping Url Shortener: MVC 2 project that Shortens urls Fully functioning 'bare bones' url shortening website. Just 1 page to create and display the short url. 'API' ...Made In Hell: Small console game. Just a training in code writings.manx: manx is a system for managing catalogs of technical documents. The system was created to handle the needs of the vintage computing community with ...ntn: playing around with new featuresOpen Bitrac: Bitrac is ASP.NET Blog SystemOpenNETCF.WindowsMobile.Ink: The Mobile Ink Library is a .NET component that provides support for the new Windows Mobile 6 WISP Lite API in your .NET Compact Framework applicat...Proxy Switch: Proxy switch is a program which allows the user to easily switch between a configured proxy server and a home network. The program is developed in ...Samcrypt: .Seoftware Evoluion Repository Mining: Project for mining data about develpoment effort from svn repository.SharePoint 2010 Bulk Document Importer: Need to import/migrate files and folders from servers and network shares into SharePoint 2010 document libraries? This free commandline application...SL2 - A Scala interpreter for L2: A simple L2 Interpreter. Just a project for a class.sMAPedit: -SocialCare: SocialCare - Team EUSOCIALSqlDiffFramework-A Visual Differencing Engine for Dissimilar Data Sources: Unique in database comparison, SDF lets you compare live data--or saved snapshots--from any combination of SQL Server, Oracle, MySql, or ODBC data ...Yasminuroban: Yasminuroban is an open source "Sokoban" (aka "Warehouse Keeper" or "Boxes") alike game totally written in DHTML (JavaScript, CSS and HTML) that us...Хрень для ао: Test project to implement Bot.New ReleasesAntySpam Microsoft Outlook Plugin: AntySpam Microsoft Outlook 2010 Plugin v.2.0.1: this release only tested on MS Outlook 2010 version: 14.0.4536.1000 (32-bit and 64-bit) part of Microsoft Office Professional Plus 2010. Source pro...AppFabric Caching Admin Tool: AppFabric Caching Admin Tool 1.2: System Requirements:.NET 4.0 RC AppFabric Caching Beta2 Refresh Test On:Win 7 (64x) Note: Must run as Administrator !!!AutoSPInstaller: Powershell script to pre-download prerequisites: This script will download all files required by Prerequisiteinstaller.exe in advance, in order to support an 'offline' installation of SharePoint 2...BeanProxy: BeanProxy 2.5: BeanProxy is a C# (.NET 3.5) library housing classes that facilitates unit testing. Any non-static, public interface/class/or abstract class can be...Bluetooth Radar: Verison 2.2.1: Please follow this link for the latest release - http://bluetoothradar.codeplex.com/releases/view/44232CSS 360 Planetary Calendar: LCA: Upload your LCA ppt pieces here. Then someone can merge them together.DeskNotes: DeskNotes 2.1.2: Version in development which features following improvements over DeskNotes 2.1.1: Each DeskNote can be made switchable between other windows on Wi...DotNetNuke Russian Language packs: Core Russian Language Pack for DNN 05.04.01: Core Russian Resource Language Pack for DNN 05.04.01 Русский языковый пакет для DNN 05.04.01DotNetNuke® Community Edition: 05.04.01: Major Highlights Fixed issue with assembly version type. Fixed issue with multiple cancel buttons on Add User screen. Fixed issue with ve...Event Scavenger: Version 3.2: Tweaked the import foreign logs functionality. Set version to 3.2 for Admin tool, service and database. Viewer unaffected.Event Scavenger: Version 3.2 stable: Update viewer version to 3.2 for consistency. Minor changes for rest.Event Scavenger: Version 3.2.2: Added setting to enable/disable creation of historic data.FIM 2010 PowerShell Cmdlets: Initial Release of FIM 2010 PowerShell Cmdlets: Initial release of FIM 2010 PowerShell cmdlets based on open source FIM web service client. Install by running installutil on Quest.FIMPowerhellSna...Fix.ly: Fix.ly 0.2: Fixed a bug where non-verbose mode would not workJobping Url Shortener: Deployment Code v0.1: Contains only the files necessary to run the Url Shortener website. Just provide a valid connection string in the web.configMetabolite Enterprise Libraries for EPiServer CMS using Page Type Builder: Metabolite Enterprise Libraries 1.1: This is the release of the Metabolite Enterprise Libraries 1.1 for use with EPiServer 5 R2 SP2 and Page Type Builder 1.1. If you want to get the s...Metabolite Enterprise Libraries for EPiServer CMS using Page Type Builder: Metabolite Enterprise Libraries 1.1 (source): This is the source code release of the Metabolite Enterprise Libraries 1.1 for use with EPiServer 5 R2 SP2 and Page Type Builder 1.1.MVC Music Store: MVC Music Store v0.8: This is the initial release of the MVC Music Store Tutorial. Download contains source and a tutorial document in PDF format.MyWSAT - ASP.NET Membership Administration Tool: MyWSAT v3.5.2: MyWSAT 3.5.2 Update Notes - April 28th 2010 1.) Fixed theme engine for administration area. Now I can create theme packages to make them available ...N2 CMS: 2.0 rc2: N2 is a lightweight CMS framework for ASP.NET. It helps you build great web sites that anyone can update. Major Changes (1.5 -> 2.0 release candid...NodeXL: Network Overview, Discovery and Exploration for Excel: NodeXL Excel 2007 Template, version 1.0.1.122: The NodeXL Excel 2007 template displays a network graph using edge and vertex lists stored in an Excel 2007 workbook. What's NewThis version signi...nRoute Framework: nRoute.Toolkit Release Version 0.4.5: Release Targets, Silverlight and WPF: - Targets Silverlight 4 for Web - Targets WPF in .NET 4 for Desktop nRoute Dependencies: - System.Windows...NSIS Autorun: NSIS Autorun 0.1.4: NSIS Autorun 0.1.4 This release includes source code, application binary, and example materials.OpenNETCF.WindowsMobile.Ink: Initial Release: This is the source as originally hosted in the OpenNETCF SVN server.Resharper Settings Manager: RSM v2.1: Warning! The 'Load Settings File...' menu item won't show up in VS 2008. Will release an update soon. ChangesReworked plug-in options UI: Split RSM...RoTwee: RoTwee (11.1.0.0): Rotation is improved from 11.0.0.3.SharePoint 2010 Bulk Document Importer: SharePoint 2010 Bulk Document Importer 1.0.0.0: Features in 1.0.0.0 Command line interface Import folders and files with all subfolders Can be run from outside the SharePoint Server. Every a...sMAPedit: sMAPedit v0.6 (Base): + base version containing the applicaion & html resourcesSocialCare: SocialCare_src: Codigo Fonte da Aplicação e Banco de DadosTFS Code Comment Checking Policy (CCCP): CCCP 4.0 for VS2010: This release installs side-by-side with CCCP 3.0 for VS2008 SP1.VCC: Latest build, v2.1.30428.0: Automatic drop of latest buildVCC: Latest build, v2.1.30428.1: Automatic drop of latest buildVCC: Latest build, v2.1.30428.2: Automatic drop of latest buildХрень для ао: Первый релиз: Пробую что это такое.Most Popular ProjectsRawrWBFS ManagerAJAX Control Toolkitpatterns & practices – Enterprise LibrarySilverlight ToolkitMicrosoft SQL Server Product Samples: DatabaseWindows Presentation Foundation (WPF)ASP.NETiTuner - The iTunes CompanionMicrosoft SQL Server Community & SamplesMost Active Projectspatterns & practices – Enterprise LibraryRawrHydroServer - CUAHSI Hydrologic Information System ServerIonics Isapi Rewrite FilterGMap.NET - Great Maps for Windows Forms & PresentationNB_Store - Free DotNetNuke Ecommerce Catalog ModuleParticle Plot PivotSqlDiffFramework-A Visual Differencing Engine for Dissimilar Data SourcesN2 CMSBlogEngine.NET

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  • Building services with .Net Part 1

    - by Allan Rwakatungu
    On the 26th of May 2010 , I made a presentation to the .NET user group meeting (thanks to Malisa Ncube for organizing this event every month … ). If you missed my presentation , we talked about why we should all be building services … better still using the .NET framework. This blog post is an introduction to services , why you would want to build services and how you can build services using the .NET framework. What is a service? OASIS defines service as "a mechanism to enable access to one or more capabilities, where the access is provided using a prescribed interface and is exercised consistent with constraints and policies as specified by the service description." [1]. If the above definition sounds to academic , you can also define a service as loosely coupled units of functionality that have no calls to each other embedded in the. Instead of services embedding calls to each other in their service code they use defined protocols that describe how services pass and parse messages. This is a good way to think about services if you’re from an objected oriented background. While in object oriented programming functions make calls to each other, in service oriented programming, functions pass messages between each other. Why would you want to use services? 1. If your enterprise architecture looks like this   Services are the building blocks for SOA . With SOA you can move away from the sphaggetti infrastructure that is common in most enterprises. The complexity or lack of visibility of the integration points in your enterprises makes it difficult and costly to implement new initiatives and changes into the business - and even impossible in some cases - as it is not possible to identify the impact a change in one system might have to other systems. With services you can move to an architecture like this Your building blocks from Spaghetti infrastructure to something that is more well-defined and manageable to achieve cost efficiency and not least business agility - enabling you to react to changes in the market with speed and achieve operational efficiency and control are services. 2. If you want to become the Gates or Zuckerburger. Have you heard about Web 2.0 ? Mashups? Software as a service (SAAS) ? Cloud computing ?   They all offer you the opportunity to have scalable but low cost business models and they built using services.  Some of my favorite companies that leverage services for their business models include  https://www.salesforce.com/ (cloud CRM) http://www. twitter.com (more people use twitter clients built by 3rd parties than their official clients) http://www.kayak.com/ (compares data from other travel sites to give information to users in one location) Services with the .NET framework      If you are a .NET developer and you want to develop services, Windows Communication Framework (WCF) is the tool for you. WCF is Microsoft’s unified programming model (service model) for building service oriented applications. ( Before .NET 3.0 you had several models for programming services in .NET including .NET remoting, Web services (ASMX), COM +, Microsoft Messaging queuing (MSMQ) etc, after .NET 3.0 the programming model was unified into one i.e. WCF ). Windows Communication Framework (WCF) provides you 1. An Software Development Kit (SDK) for creating SOA applications 2. A runtime for running services on the Windows platform Why should you use Windows Communication Foundation if you’re programming services?   1. It supports interoperable and open standards e.g. WS* protocols for programming SOAP services 2. It has a unified programming model. Whether you use TCP or Http or Pipes or transmitting using Messaging Queues, programmers need to learn just one way to program. Previously you had .NET remoting, MSMQ, Web services, COM+ and they were all done differently 3. Productive programming model You don’t have to worry about all the plumbing involved to write services. You have a rich declarative programming model to add stuff like logging, transactions, and reliable messages in-built in the Windows Communication Framework. Understanding services in WCF The basic principles of WCF are as easy as ABC A – Address This is where the service is located B- Binding This describes how you communicate with the service e.g. Use TCP, HTTP or both. How to exchange security information with the service etc. C – Contract This defines what the service can do. E.g. Pay water bill, Make a phone call A - Addresses In WCF, an address is a combination of transport, server name, port and path Example addresses may include http://localhost:8001 net.tcp://localhost:8002/MyService net.pipe://localhost/MyPipe net.msmq://localhost/private/MyService net.msmq://localhost/MyService B- Binding   There are numerous ways to communicate with services , different ways that a message can be formatted/sent/secured, that allows you to tailor your service for the compatibility/performance you require for your solution. Transport You can use HTTP TCP MSMQ , Named pipes, Your own custom transport etc Message You  can send a plain text binary, Message Transmission Optimization Mechanism (MTOM) message Communication security No security Transport security Message security Authenticating and authorizing callers etc Behaviour You service can support Transactions Be reliable Use queues Support ajax etc C - Contract You define what your service can do using Service contracts :- Define operations that your service can do, communications and behaviours Data contracts :- Define the messages that are passed from and into your service and how they are formatted Fault contracts :- Defines errors types in your service   As an example, suppose your service service shows money. You define your service contract using a interface [ServiceContract] public interface IShowMeTheMoney {   [OperationContract]    Money Show(); } You define the data contract by annotating a class it with the Data Contract attribute and fields you want to pass in the message as Data Members. (Note:- In the latest versions of WCF you dont have to use attributes if you passing all the objects properties in the message) [DataContract] public Money {   [DataMember]   public string Currency { get; set; }   [DataMember]   public Decimal Amount { get; set; }   public string Comment { get; set; } } Features of Windows Communication Foundation Windows Communication Foundation is not only simple but feature rich , offering you several options to tweak your service to fit your business requirements. Some of the features of WCF include 1. Workflow services You can combine WCF with Windows WorkFlow Foundation (WWF) to write workflow type services 2. Control how your data (messages) are transferred and serialized e.g. you can serialize your business objects as XML or binary 3. control over session management , instance creation and concurrency management without writing code if you like 4. Queues and reliable sessions. You can store messages from the sending client and later forward them to the receiving application. You can also guarantee that messages will arrive at their destincation. 5.Transactions:  You can have different services participate in a transaction operations that can be rolled back if needed 6. Security. WCF has rich features for authorization and authentication  as well as keep audit trails 7. Web programming model. WCF allows developers to expose services as non SOAP endpoints 8. Inbuilt features that you can use to write JSON and services that support AJAX applications And lots more In my next blog I will show you how you can use WCF features to write a real world business service.               Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 ]] /* 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-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

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  • Using a "white list" for extracting terms for Text Mining, Part 2

    - by [email protected]
    In my last post, we set the groundwork for extracting specific tokens from a white list using a CTXRULE index. In this post, we will populate a table with the extracted tokens and produce a case table suitable for clustering with Oracle Data Mining. Our corpus of documents will be stored in a database table that is defined as create table documents(id NUMBER, text VARCHAR2(4000)); However, any suitable Oracle Text-accepted data type can be used for the text. We then create a table to contain the extracted tokens. The id column contains the unique identifier (or case id) of the document. The token column contains the extracted token. Note that a given document many have many tokens, so there will be one row per token for a given document. create table extracted_tokens (id NUMBER, token VARCHAR2(4000)); The next step is to iterate over the documents and extract the matching tokens using the index and insert them into our token table. We use the MATCHES function for matching the query_string from my_thesaurus_rules with the text. DECLARE     cursor c2 is       select id, text       from documents; BEGIN     for r_c2 in c2 loop        insert into extracted_tokens          select r_c2.id id, main_term token          from my_thesaurus_rules          where matches(query_string,                        r_c2.text)>0;     end loop; END; Now that we have the tokens, we can compute the term frequency - inverse document frequency (TF-IDF) for each token of each document. create table extracted_tokens_tfidf as   with num_docs as (select count(distinct id) doc_cnt                     from extracted_tokens),        tf       as (select a.id, a.token,                            a.token_cnt/b.num_tokens token_freq                     from                        (select id, token, count(*) token_cnt                        from extracted_tokens                        group by id, token) a,                       (select id, count(*) num_tokens                        from extracted_tokens                        group by id) b                     where a.id=b.id),        doc_freq as (select token, count(*) overall_token_cnt                     from extracted_tokens                     group by token)   select tf.id, tf.token,          token_freq * ln(doc_cnt/df.overall_token_cnt) tf_idf   from num_docs,        tf,        doc_freq df   where df.token=tf.token; From the WITH clause, the num_docs query simply counts the number of documents in the corpus. The tf query computes the term (token) frequency by computing the number of times each token appears in a document and divides that by the number of tokens found in the document. The doc_req query counts the number of times the token appears overall in the corpus. In the SELECT clause, we compute the tf_idf. Next, we create the nested table required to produce one record per case, where a case corresponds to an individual document. Here, we COLLECT all the tokens for a given document into the nested column extracted_tokens_tfidf_1. CREATE TABLE extracted_tokens_tfidf_nt              NESTED TABLE extracted_tokens_tfidf_1                  STORE AS extracted_tokens_tfidf_tab AS              select id,                     cast(collect(DM_NESTED_NUMERICAL(token,tf_idf)) as DM_NESTED_NUMERICALS) extracted_tokens_tfidf_1              from extracted_tokens_tfidf              group by id;   To build the clustering model, we create a settings table and then insert the various settings. Most notable are the number of clusters (20), using cosine distance which is better for text, turning off auto data preparation since the values are ready for mining, the number of iterations (20) to get a better model, and the split criterion of size for clusters that are roughly balanced in number of cases assigned. CREATE TABLE km_settings (setting_name  VARCHAR2(30), setting_value VARCHAR2(30)); BEGIN  INSERT INTO km_settings (setting_name, setting_value) VALUES     VALUES (dbms_data_mining.clus_num_clusters, 20);  INSERT INTO km_settings (setting_name, setting_value)     VALUES (dbms_data_mining.kmns_distance, dbms_data_mining.kmns_cosine);   INSERT INTO km_settings (setting_name, setting_value) VALUES     VALUES (dbms_data_mining.prep_auto,dbms_data_mining.prep_auto_off);   INSERT INTO km_settings (setting_name, setting_value) VALUES     VALUES (dbms_data_mining.kmns_iterations,20);   INSERT INTO km_settings (setting_name, setting_value) VALUES     VALUES (dbms_data_mining.kmns_split_criterion,dbms_data_mining.kmns_size);   COMMIT; END; With this in place, we can now build the clustering model. BEGIN     DBMS_DATA_MINING.CREATE_MODEL(     model_name          => 'TEXT_CLUSTERING_MODEL',     mining_function     => dbms_data_mining.clustering,     data_table_name     => 'extracted_tokens_tfidf_nt',     case_id_column_name => 'id',     settings_table_name => 'km_settings'); END;To generate cluster names from this model, check out my earlier post on that topic.

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