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• Code Reuse is (Damn) Hard

  - by James Michael Hare

  Being a development team lead, the task of interviewing new candidates was part of my job.  Like any typical interview, we started with some easy questions to get them warmed up and help calm their nerves before hitting the hard stuff. One of those easier questions was almost always: “Name some benefits of object-oriented development.”  Nearly every time, the candidate would chime in with a plethora of canned answers which typically included: “it helps ease code reuse.”  Of course, this is a gross oversimplification.  Tools only ease reuse, its developers that ultimately can cause code to be reusable or not, regardless of the language or methodology. But it did get me thinking…  we always used to say that as part of our mantra as to why Object-Oriented Programming was so great.  With polymorphism, inheritance, encapsulation, etc. we in essence set up the concepts to help facilitate reuse as much as possible.  And yes, as a developer now of many years, I unquestionably held that belief for ages before it really struck me how my views on reuse have jaded over the years.  In fact, in many ways Agile rightly eschews reuse as taking a backseat to developing what's needed for the here and now.  It used to be I was in complete opposition to that view, but more and more I've come to see the logic in it.  Too many times I've seen developers (myself included) get lost in design paralysis trying to come up with the perfect abstraction that would stand all time.  Nearly without fail, all of these pieces of code become obsolete in a matter of months or years. It’s not that I don’t like reuse – it’s just that reuse is hard.  In fact, reuse is DAMN hard.  Many times it is just a distraction that eats up architect and developer time, and worse yet can be counter-productive and force wrong decisions.  Now don’t get me wrong, I love the idea of reusable code when it makes sense.  These are in the few cases where you are designing something that is inherently reusable.  The problem is, most business-class code is inherently unfit for reuse! Furthermore, the code that is reusable will often fail to be reused if you don’t have the proper framework in place for effective reuse that includes standardized versioning, building, releasing, and documenting the components.  That should always be standard across the board when promoting reusable code.  All of this is hard, and it should only be done when you have code that is truly reusable or you will be exerting a large amount of development effort for very little bang for your buck. But my goal here is not to get into how to reuse (that is a topic unto itself) but what should be reused.  First, let’s look at an extension method.  There’s many times where I want to kick off a thread to handle a task, then when I want to reign that thread in of course I want to do a Join on it.  But what if I only want to wait a limited amount of time and then Abort?  Well, I could of course write that logic out by hand each time, but it seemed like a great extension method: 1: public static class ThreadExtensions 2: { 3: public static bool JoinOrAbort(this Thread thread, TimeSpan timeToWait) 4: { 5: bool isJoined = false; 6:  7: if (thread != null) 8: { 9: isJoined = thread.Join(timeToWait); 10:  11: if (!isJoined) 12: { 13: thread.Abort(); 14: } 15: } 16: return isJoined; 17: } 18: } 19:  When I look at this code, I can immediately see things that jump out at me as reasons why this code is very reusable.  Some of them are standard OO principles, and some are kind-of home grown litmus tests: Single Responsibility Principle (SRP) – The only reason this extension method need change is if the Thread class itself changes (one responsibility). Stable Dependencies Principle (SDP) – This method only depends on classes that are more stable than it is (System.Threading.Thread), and in itself is very stable, hence other classes may safely depend on it. It is also not dependent on any business domain, and thus isn't subject to changes as the business itself changes. Open-Closed Principle (OCP) – This class is inherently closed to change. Small and Stable Problem Domain – This method only cares about System.Threading.Thread. All-or-None Usage – A user of a reusable class should want the functionality of that class, not parts of that functionality.  That’s not to say they most use every method, but they shouldn’t be using a method just to get half of its result. Cost of Reuse vs. Cost to Recreate – since this class is highly stable and minimally complex, we can offer it up for reuse very cheaply by promoting it as “ready-to-go” and already unit tested (important!) and available through a standard release cycle (very important!). Okay, all seems good there, now lets look at an entity and DAO.  I don’t know about you all, but there have been times I’ve been in organizations that get the grand idea that all DAOs and entities should be standardized and shared.  While this may work for small or static organizations, it’s near ludicrous for anything large or volatile. 1: namespace Shared.Entities 2: { 3: public class Account 4: { 5: public int Id { get; set; } 6:  7: public string Name { get; set; } 8:  9: public Address HomeAddress { get; set; } 10:  11: public int Age { get; set;} 12:  13: public DateTime LastUsed { get; set; } 14:  15: // etc, etc, etc... 16: } 17: } 18:  19: ... 20:  21: namespace Shared.DataAccess 22: { 23: public class AccountDao 24: { 25: public Account FindAccount(int id) 26: { 27: // dao logic to query and return account 28: } 29:  30: ... 31:  32: } 33: } Now to be fair, I’m not saying there doesn’t exist an organization where some entites may be extremely static and unchanging.  But at best such entities and DAOs will be problematic cases of reuse.  Let’s examine those same tests: Single Responsibility Principle (SRP) – The reasons to change for these classes will be strongly dependent on what the definition of the account is which can change over time and may have multiple influences depending on the number of systems an account can cover. Stable Dependencies Principle (SDP) – This method depends on the data model beneath itself which also is largely dependent on the business definition of an account which can be very inherently unstable. Open-Closed Principle (OCP) – This class is not really closed for modification.  Every time the account definition may change, you’d need to modify this class. Small and Stable Problem Domain – The definition of an account is inherently unstable and in fact may be very large.  What if you are designing a system that aggregates account information from several sources? All-or-None Usage – What if your view of the account encompasses data from 3 different sources but you only care about one of those sources or one piece of data?  Should you have to take the hit of looking up all the other data?  On the other hand, should you have ten different methods returning portions of data in chunks people tend to ask for?  Neither is really a great solution. Cost of Reuse vs. Cost to Recreate – DAOs are really trivial to rewrite, and unless your definition of an account is EXTREMELY stable, the cost to promote, support, and release a reusable account entity and DAO are usually far higher than the cost to recreate as needed. It’s no accident that my case for reuse was a utility class and my case for non-reuse was an entity/DAO.  In general, the smaller and more stable an abstraction is, the higher its level of reuse.  When I became the lead of the Shared Components Committee at my workplace, one of the original goals we looked at satisfying was to find (or create), version, release, and promote a shared library of common utility classes, frameworks, and data access objects.  Now, of course, many of you will point to nHibernate and Entity for the latter, but we were looking at larger, macro collections of data that span multiple data sources of varying types (databases, web services, etc). As we got deeper and deeper in the details of how to manage and release these items, it quickly became apparent that while the case for reuse was typically a slam dunk for utilities and frameworks, the data access objects just didn’t “smell” right.  We ended up having session after session of design meetings to try and find the right way to share these data access components. When someone asked me why it was taking so long to iron out the shared entities, my response was quite simple, “Reuse is hard...”  And that’s when I realized, that while reuse is an awesome goal and we should strive to make code maintainable, often times you end up creating far more work for yourself than necessary by trying to force code to be reusable that inherently isn’t. Think about classes the times you’ve worked in a company where in the design session people fight over the best way to implement a class to make it maximally reusable, extensible, and any other buzzwordable.  Then think about how quickly that design became obsolete.  Many times I set out to do a project and think, “yes, this is the best design, I can extend it easily!” only to find out the business requirements change COMPLETELY in such a way that the design is rendered invalid.  Code, in general, tends to rust and age over time.  As such, writing reusable code can often be difficult and many times ends up being a futile exercise and worse yet, sometimes makes the code harder to maintain because it obfuscates the design in the name of extensibility or reusability. So what do I think are reusable components? Generic Utility classes – these tend to be small classes that assist in a task and have no business context whatsoever. Implementation Abstraction Frameworks – home-grown frameworks that try to isolate changes to third party products you may be depending on (like writing a messaging abstraction layer for publishing/subscribing that is independent of whether you use JMS, MSMQ, etc). Simplification and Uniformity Frameworks – To some extent this is similar to an abstraction framework, but there may be one chosen provider but a development shop mandate to perform certain complex items in a certain way.  Or, perhaps to simplify and dumb-down a complex task for the average developer (such as implementing a particular development-shop’s method of encryption). And what are less reusable? Application and Business Layers – tend to fluctuate a lot as requirements change and new features are added, so tend to be an unstable dependency.  May be reused across applications but also very volatile. Entities and Data Access Layers – these tend to be tuned to the scope of the application, so reusing them can be hard unless the abstract is very stable. So what’s the big lesson?  Reuse is hard.  In fact it’s damn hard.  And much of the time I’m not convinced we should focus too hard on it. If you’re designing a utility or framework, then by all means design it for reuse.  But you most also really set down a good versioning, release, and documentation process to maximize your chances.  For anything else, design it to be maintainable and extendable, but don’t waste the effort on reusability for something that most likely will be obsolete in a year or two anyway.

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• Which web framework to use under Backbonejs?

  - by egidra

  For a previous project, I was using Backbonejs alongside Django, but I found out that I didn't use many features from Django. So, I am looking for a lighter framework to use underneath a Backbonejs web app. I never used Django built in templates. When I did, it was to set up the initial index page, but that's all. I did use the user management system that Django provided. I used the models.py, but never views.py. I used urls.py to set up which template the user would hit upon visiting the site. I noticed that the two features that I used most from Django was South and Tastypie, and they aren't even included with Django. Particularly, django-tastypie made it easy for me to link up my frontend models to my backend models. It made it easy to JSONify my front end models and send them to Tastypie. Although, I found myself overriding a lot of tastypie's methods for GET, PUT, POST requests, so it became useless. South made it easy to migrate new changes to the database. Although, I had so much trouble with South. Is there a framework with an easier way of handling database modifications than using South? When using South with multiple people, we had the worse time keeping our databases synced. When someone added a new table and pushed their migration to git, the other two people would spend days trying to use South's automatic migration, but it never worked. I liked how Rails had a manual way of migrating databases. Even though I used Tastypie and South a lot, I found myself not actually liking them because I ended up overriding most Tastypie methods for each Resource, and I also had the worst trouble migrating new tables and columns with South. So, I would like a framework that makes that process easier. Part of my problem was that they are too "magical". Which framework should I use? Nodejs or a lighter Python framework? Which works best with my above criteria?

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• Best Ati Radeon x1200 drivers for 12.10

  - by Jaclyn

  [Long story short is at the bottom if you don't care about my ranting] Ok, well, I have the unfortunate distinction of having an Acer Extensa 4420 (Yes, the model with the faulty motherboard, and no, I do not know how it is still working either). Long story short I need the best drivers for my Ati Radeon x1200 integrated graphics card. The Ati Propriatary drivers for 12.10 no longer supports my video card. Currently when I try to play Minecraft, or any game really, the framerate is quite terrible despite the fact that my handy dandy system load monitor says that I have plenty of memory and CPU power (Mind you, this is when I'm not playing minecraft; that kind of uses up all of my resources unless it's on the worst graphical settings, and even then I have terrible framerate, but plenty of resources left over). I tried the fglrx through a workaround guide, and it completely killed my display and I had to uninstall it. I'm considering just trying to install fglrx through synaptic, but I am hesitant to do so since I don't want a repeat of the BSBDD!!! (Black Screen of Bad Drivers 'o DOOOM!!!), so I will wait until after I get some input from you fine ladies and gentlemen on to what your advice it. ok, so I'm running xubuntu 12.10 64 bit. I upgraded from 10.10 to 11.04. Then about a month ago I went from natty to quantal via the update option in the package updater, and then I decided that I was sick of gnome so I installed xfce. I did not install new drivers from natty to when I wound up at 12.10, so that shouldn't have changed, and they were indeed quite terrible back then, but now I'm using xubuntu as my main os, so I actually need good drivers. uuuugh. Anyway, long story short: I need to know what are the best drivers available for my card, and how to install them, because I am a linux novice, and I have tried everything that I can think of, including search google. Small edit: I forgot to note that since I upgraded to 12.10, my VGA out does not work (I haven't had a chance to try the s-video yet), and possibly related, the USB port on that side of my laptop does not work anymore either.

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• TechEd 2010 Day Three: The Database Designer (Isn't)

  - by BuckWoody

  Yesterday at TechEd 2010 here in New Orleans I worked the front-booth, answering general SQL Server questions for the masses. I was actually a little surprised to find most of the questions I got were from folks that wanted to know more about Stream Insight and Master Data Services. In past conferences I've been asked a lot of "free consulting" questions, about problems folks have had from older products. I don't mind that a bit - in fact, I'm always happy to help in any way I can. But this time people are really interested in the new features in the product, and I like that they are thinking ahead, not just having to solve problems in production. My presentation was on "Database Design in an Hour". We had the usual fun, and SideShow Bob made an appearance - I kid you not. The guy in the back of the room looked just like Sideshow Bob, so I quickly held a "bes thair" contest, and he won. Duing the presentation, I explain the tools you can use to design databases. I also explain that the "Database Designer" tool in SQL Server Management Studio (SSMS) isn't truly a desinger - it uses non-standard notation, doesn't have a meta-data dictionary, and worst of all, it works at the physical level. In other words, whatever you do in SSMS will automatically change the field/table/relationship structures in the database. We fixed this in SSMS 2008 and higher by adding an option to block that, but the tool is not a good design function nonetheless. To be fair, no one I know of at Microsoft recommends that it is - but I was shocked to hear so many developers in the room defending it as a good tool. I think the main issue for someone who doesn't have to work with Relational Systems a great deal is that it can be difficult to figure out Foreign Keys. The syntax makes them look "backwards", so it's just easier to grab a field and place it on the table you want to point to. There are options. You can download a couple of free tools (CA has a community edition of ER-WIN, Quest has one, and Embarcadero also has one) and if you design more than one or two databases a year, it may be worth buying a true design tool. For years I used Visio, but we changed it so that it doesn't forward-engineer (create the DDL) any more, so it isn't a true design tool either. So investigate those free and not-so-free tools. You'll find they help you in your job - but stay away from the Database Designer in SSMS. Or I'll send Sideshow Bob over there to straighten you out. Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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• Taking web sites offline for demonstration

  While working in software development in general, and in web development for a couple of customers it is quite common that it is necessary to provide a test bed where the client is able to get an image, or better said, a feeling for the visions and ideas you are talking about. Usually here at IOS Indian Ocean Software Ltd. we set up a demo web site on one of our staging servers, and provide credentials to the customer to access and review our progress and work ad hoc. This gives us the highest flexibility on both sides, as the test bed is simply online and available 24/7. We can update the structure, the UI and data at any time, and the client is able to view it as it suits best for her/him. Limited or lack of online connectivity But what is going to happen when your client is not capable to be online - no matter for what reasons; here are some more obvious ones: No internet connection (permanently or temporarily) Expensive connection, ie. mobile data package, stay at a hotel, etc. Presentation devices at an exhibition, ie. using tablets or iPads Being abroad for a certain time, and only occasionally online No network coverage, especially on mobile Bad infrastructure, like ie. in Third World countries Providing a catalogue on CD or USB pen drive Anyway, it doesn't matter really. We should be able to provide a solution for the circumstances of our customers. Presentation during an exhibition Recently, we had the following request from a customer: Is it possible to let us have a desktop version of ResortWork.co.uk that we can use for demo purposes at the forthcoming Ski Shows? It would allow us to let stand visitors browse the sites on an iPad to view jobs and training directory course listings. Yes, sure we can do that. Eventually, you might think why don't they simply use 3G enabled iPads for that purpose? As stated above, there might be several reasons for that - low coverage, expensive data packages, etc. Anyway, it is not a question on how to circumvent the request but to deliver a solution to that. Possible solutions... or not? We already did offline websites earlier, and even established complete mirrors of one or two web sites on our systems. There are actually several possibilities to handle this kind of request, and it mainly depends on the system or device where the offline site should be available on. Here, it is clearly expressed that we have to address this on an Apple iPad, well actually, I think that they'd like to use multiple devices during their exhibitions. Following is an overview of possible solutions depending on the technology or device in use, and how it can be done: Replication of source files and database The above mentioned web site is running on ASP.NET, IIS and SQL Server. In case that a laptop or slate runs a Windows OS, the easiest way would be to take a snapshot of the source files and database, and transfer them as local installation to those Windows machines. This approach would be fully operational on the local machine. Saving pages for offline usage This is actually a quite tedious job but still practicable for small web sites Tool based approach to 'harvest' the web site There quite some tools in the wild that could handle this job, namely wget, httrack, web copier, etc. Screenshots bundled as PDF document Not really... ;-) Creating screencast or video Simply navigate through your website and record your desktop session. Actually, we are using this kind of approach to track down difficult problems in order to see and understand exactly what the user was doing to cause an error. Of course, this list isn't complete and I'd love to get more of your ideas in the comments section below the article. Preparations for offline browsing The original website is dynamically and data-driven by ASP.NET, and looks like this: As we have to put the result onto iPads we are going to choose the tool-based approach to 'download' the whole web site for offline usage. Again, depending on the complexity of your web site you might have to check which of the applications produces the best results for you. My usual choice is to use wget but in this case, we run into problems related to the rewriting of hyperlinks. As a consequence of that we opted for using HTTrack. HTTrack comes in different flavours, like console application but also as either GUI (WinHTTrack on Windows) or Web client (WebHTTrack on Linux/Unix/BSD). Here's a brief description taken from the original website about HTTrack: HTTrack is a free (GPL, libre/free software) and easy-to-use offline browser utility. It allows you to download a World Wide Web site from the Internet to a local directory, building recursively all directories, getting HTML, images, and other files from the server to your computer. HTTrack arranges the original site's relative link-structure. Simply open a page of the "mirrored" website in your browser, and you can browse the site from link to link, as if you were viewing it online. And there is an extensive documentation for all options and switches online. General recommendation is to go through the HTTrack Users Guide By Fred Cohen. It covers all the initial steps you need to get up and running. Be aware that it will take quite some time to get all the necessary resources down to your machine. Actually, for our customer we run the tool directly on their web server to avoid unnecessary traffic and bandwidth. After a couple of runs and some additional fine-tuning - explicit inclusion or exclusion of various external linked web sites - we finally had a more or less complete offline version available. A very handsome feature of HTTrack is the error/warning log after completing the download. It contains some detailed information about errors that appeared on the pages and the links within the pages that have been processed. Error: "Bad Request" (400) at link www.resortwork.co.uk/job-details_Ski_hire:tech_or_mgr_or_driver_37854.aspx (from www.resortwork.co.uk/Jobs_A_to_Z.aspx)Error: "Not Found" (404) at link www.247recruit.net/images/applynow.png (from www.247recruit.net/css/global.css)Error: "Not Found" (404) at link www.247recruit.net/activate.html (from www.247recruit.net/247recruit_tefl_jobs_network.html) In our situation, we took the records of HTTP 400/404 errors and passed them to the web development department. Improvements are to be expected soon. ;-) Quality assurance on the full-featured desktop Unfortunately, the generated output of HTTrack was still incomplete but luckily there were only images missing. Being directly on the web server we simply copied the missing images from the original source folder into our offline version. After that, we created an archive and transferred the file securely to our local workspace for further review and checks. From that point on, it wasn't necessary to get any more files from the original web server, and we could focus ourselves completely on the process of browsing and navigating through the offline version to isolate visual differences and functional problems. As said, the original web site runs on ASP.NET Web Forms and uses Postback calls for interaction like search, pagination and partly for navigation. This is the main field of improving the offline experience. Of course, same as for standard web development it is advised to test with various browsers, and strangely we discovered that the offline version looked pretty good on Firefox, Chrome and Safari, but not in Internet Explorer. A quick look at the HTML source shed some light on this, and there are conditional CSS inclusions based on the user agent. HTTrack is not acting as Internet Explorer and so we didn't have the necessary overrides for this browser. Not problematic after all in our case, but you might have to pay attention to this and get the IE-specific files explicitly. And while having a view at the source code, we also found out that HTTrack actually modifies the generated HTML output. In several occasions we discovered that <div> elements were converted into <table> constructs for no obvious reason; even nested structures. Search 'e'nd destroy - sed (or Notepad++) to the rescue During our intensive root cause analysis for a couple of HTML/CSS problems that needed some extra attention it is very helpful to be familiar with any editor that allows search and replace over multiple files like, ie. sed - stream editor for filtering and transforming text on Linux or my personal favourite Notepad++ on Windows. This allowed us to quickly fix a lot of anchors with onclick attributes and Javascript code that was addressed to ASP.NET files instead of their generated HTML counterparts, like so: grep -lr -e '.aspx' * | xargs sed -e 's/.aspx/.html?/g' The additional question mark after the HTML extension helps to separate the query string from the actual target and solved all our missing hyperlinks very fast. The same can be done in Notepad++ on Windows, too. Just use the 'Replace in files' feature and you are settled. Especially, in combination with Regular Expressions (regex). Landscape of browsers Okay, after several runs of HTML/CSS code analysis, searching and replacing some strings in a pool of more than 4.000 files, we finally had a very good match of an offline browsing experience in Firefox and Chrome on Linux. Next, we transferred that modified set of files to a Windows 8 machine for review on Firefox, Chrome and Internet Explorer 7 to 10, and a Mac mini running Mac OS X 10.7 to check the output on Safari and again on Chrome. Besides IE, for reasons already mentioned above, the results were identical. And last but not least it was about to check web site on tablets. Please continue to read on the following articles: Taking web sites offline for demonstration on Galaxy Tablet Taking web sites offline for demonstration on iPad

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• Developing a SQL Server Function in a Test-Harness.

  - by Phil Factor

  /* Many times, it is a lot quicker to take some pain up-front and make a proper development/test harness for a routine (function or procedure) rather than think ‘I’m feeling lucky today!’. Then, you keep code and harness together from then on. Every time you run the build script, it runs the test harness too.  The advantage is that, if the test harness persists, then it is much less likely that someone, probably ‘you-in-the-future’  unintentionally breaks the code. If you store the actual code for the procedure as well as the test harness, then it is likely that any bugs in functionality will break the build rather than to introduce subtle bugs later on that could even slip through testing and get into production.   This is just an example of what I mean.   Imagine we had a database that was storing addresses with embedded UK postcodes. We really wouldn’t want that. Instead, we might want the postcode in one column and the address in another. In effect, we’d want to extract the entire postcode string and place it in another column. This might be part of a table refactoring or int could easily be part of a process of importing addresses from another system. We could easily decide to do this with a function that takes in a table as its parameter, and produces a table as its output. This is all very well, but we’d need to work on it, and test it when you make an alteration. By its very nature, a routine like this either works very well or horribly, but there is every chance that you might introduce subtle errors by fidding with it, and if young Thomas, the rather cocky developer who has just joined touches it, it is bound to break.     right, we drop the function we’re developing and re-create it. This is so we avoid the problem of having to change CREATE to ALTER when working on it. */ IF EXISTS(SELECT * FROM sys.objects WHERE name LIKE ‘ExtractPostcode’                                      and schema_name(schema_ID)=‘Dbo’)     DROP FUNCTION dbo.ExtractPostcode GO   /* we drop the user-defined table type and recreate it */ IF EXISTS(SELECT * FROM sys.types WHERE name LIKE ‘AddressesWithPostCodes’                                    and schema_name(schema_ID)=‘Dbo’)   DROP TYPE dbo.AddressesWithPostCodes GO /* we drop the user defined table type and recreate it */ IF EXISTS(SELECT * FROM sys.types WHERE name LIKE ‘OutputFormat’                                    and schema_name(schema_ID)=‘Dbo’)   DROP TYPE dbo.OutputFormat GO   /* and now create the table type that we can use to pass the addresses to the function */ CREATE TYPE AddressesWithPostCodes AS TABLE ( AddressWithPostcode_ID INT IDENTITY PRIMARY KEY, –because they work better that way! Address_ID INT NOT NULL, –the address we are fixing TheAddress VARCHAR(100) NOT NULL –The actual address ) GO CREATE TYPE OutputFormat AS TABLE (   Address_ID INT PRIMARY KEY, –the address we are fixing   TheAddress VARCHAR(1000) NULL, –The actual address   ThePostCode VARCHAR(105) NOT NULL – The Postcode )   GO CREATE FUNCTION ExtractPostcode(@AddressesWithPostCodes AddressesWithPostCodes READONLY)  /** summary:   > This Table-valued function takes a table type as a parameter, containing a table of addresses along with their integer IDs. Each address has an embedded postcode somewhere in it but not consistently in a particular place. The routine takes out the postcode and puts it in its own column, passing back a table where theinteger key is accompanied by the address without the (first) postcode and the postcode. If no postcode, then the address is returned unchanged and the postcode will be a blank string Author: Phil Factor Revision: 1.3 date: 20 May 2014 example:      – code: returns:   > Table of  Address_ID, TheAddress and ThePostCode. **/     RETURNS @FixedAddresses TABLE   (   Address_ID INT, –the address we are fixing   TheAddress VARCHAR(1000) NULL, –The actual address   ThePostCode VARCHAR(105) NOT NULL – The Postcode   ) AS – body of the function BEGIN DECLARE @BlankRange VARCHAR(10) SELECT  @BlankRange = CHAR(0)+‘- ‘+CHAR(160) INSERT INTO @FixedAddresses(Address_ID, TheAddress, ThePostCode) SELECT Address_ID,          CASE WHEN start>0 THEN REPLACE(STUFF([Theaddress],start,matchlength,”),‘  ‘,‘ ‘)             ELSE TheAddress END            AS TheAddress,        CASE WHEN Start>0 THEN SUBSTRING([Theaddress],start,matchlength-1) ELSE ” END AS ThePostCode FROM (–we have a derived table with the results we need for the chopping SELECT MAX(PATINDEX([matched],‘ ‘+[Theaddress] collate SQL_Latin1_General_CP850_Bin)) AS start,         MAX( CASE WHEN PATINDEX([matched],‘ ‘+[Theaddress] collate SQL_Latin1_General_CP850_Bin)>0 THEN TheLength ELSE 0 END) AS matchlength,        MAX(TheAddress) AS TheAddress,        Address_ID FROM (SELECT –first the match, then the length. There are three possible valid matches         ‘%['+@BlankRange+'][A-Z][0-9] [0-9][A-Z][A-Z]%’, 7 –seven character postcode       UNION ALL SELECT ‘%['+@BlankRange+'][A-Z][A-Z0-9][A-Z0-9] [0-9][A-Z][A-Z]%’, 8       UNION ALL SELECT ‘%['+@BlankRange+'][A-Z][A-Z][A-Z0-9][A-Z0-9] [0-9][A-Z][A-Z]%’, 9)      AS f(Matched,TheLength) CROSS JOIN  @AddressesWithPostCodes GROUP BY [address_ID] ) WORK; RETURN END GO ——————————-end of the function————————   IF NOT EXISTS (SELECT * FROM sys.objects WHERE name LIKE ‘ExtractPostcode’)   BEGIN   RAISERROR (‘There was an error creating the function.’,16,1)   RETURN   END   /* now the job is only half done because we need to make sure that it works. So we now load our sample data, making sure that for each Sample, we have what we actually think the output should be. */ DECLARE @InputTable AddressesWithPostCodes INSERT INTO  @InputTable(Address_ID,TheAddress) VALUES(1,’14 Mason mews, Awkward Hill, Bibury, Cirencester, GL7 5NH’), (2,’5 Binney St      Abbey Ward    Buckinghamshire      HP11 2AX UK’), (3,‘BH6 3BE 8 Moor street, East Southbourne and Tuckton W     Bournemouth UK’), (4,’505 Exeter Rd,   DN36 5RP Hawerby cum BeesbyLincolnshire UK’), (5,”), (6,’9472 Lind St,    Desborough    Northamptonshire NN14 2GH  NN14 3GH UK’), (7,’7457 Cowl St, #70      Bargate Ward  Southampton   SO14 3TY UK’), (8,”’The Pippins”, 20 Gloucester Pl, Chirton Ward,   Tyne & Wear   NE29 7AD UK’), (9,’929 Augustine lane,    Staple Hill Ward     South Gloucestershire      BS16 4LL UK’), (10,’45 Bradfield road, Parwich   Derbyshire    DE6 1QN UK’), (11,’63A Northampton St,   Wilmington    Kent   DA2 7PP UK’), (12,’5 Hygeia avenue,      Loundsley Green WardDerbyshire    S40 4LY UK’), (13,’2150 Morley St,Dee Ward      Dumfries and Galloway      DG8 7DE UK’), (14,’24 Bolton St,   Broxburn, Uphall and Winchburg    West Lothian  EH52 5TL UK’), (15,’4 Forrest St,   Weston-Super-Mare    North Somerset       BS23 3HG UK’), (16,’89 Noon St,     Carbrooke     Norfolk       IP25 6JQ UK’), (17,’99 Guthrie St,  New Milton    Hampshire     BH25 5DF UK’), (18,’7 Richmond St,  Parkham       Devon  EX39 5DJ UK’), (19,’9165 laburnum St,     Darnall Ward  Yorkshire, South     S4 7WN UK’)   Declare @OutputTable  OutputFormat  –the table of what we think the correct results should be Declare @IncorrectRows OutputFormat –done for error reporting   –here is the table of what we think the output should be, along with a few edge cases. INSERT INTO  @OutputTable(Address_ID,TheAddress, ThePostcode)     VALUES         (1, ’14 Mason mews, Awkward Hill, Bibury, Cirencester, ‘,‘GL7 5NH’),         (2, ’5 Binney St   Abbey Ward    Buckinghamshire      UK’,‘HP11 2AX’),         (3, ’8 Moor street, East Southbourne and Tuckton W    Bournemouth UK’,‘BH6 3BE’),         (4, ’505 Exeter Rd,Hawerby cum Beesby   Lincolnshire UK’,‘DN36 5RP’),         (5, ”,”),         (6, ’9472 Lind St,Desborough    Northamptonshire NN14 3GH UK’,‘NN14 2GH’),         (7, ’7457 Cowl St, #70    Bargate Ward  Southampton   UK’,‘SO14 3TY’),         (8, ”’The Pippins”, 20 Gloucester Pl, Chirton Ward,Tyne & Wear   UK’,‘NE29 7AD’),         (9, ’929 Augustine lane,  Staple Hill Ward     South Gloucestershire      UK’,‘BS16 4LL’),         (10, ’45 Bradfield road, ParwichDerbyshire    UK’,‘DE6 1QN’),         (11, ’63A Northampton St,Wilmington    Kent   UK’,‘DA2 7PP’),         (12, ’5 Hygeia avenue,    Loundsley Green WardDerbyshire    UK’,‘S40 4LY’),         (13, ’2150 Morley St,     Dee Ward      Dumfries and Galloway      UK’,‘DG8 7DE’),         (14, ’24 Bolton St,Broxburn, Uphall and Winchburg    West Lothian  UK’,‘EH52 5TL’),         (15, ’4 Forrest St,Weston-Super-Mare    North Somerset       UK’,‘BS23 3HG’),         (16, ’89 Noon St,  Carbrooke     Norfolk       UK’,‘IP25 6JQ’),         (17, ’99 Guthrie St,      New Milton    Hampshire     UK’,‘BH25 5DF’),         (18, ’7 Richmond St,      Parkham       Devon  UK’,‘EX39 5DJ’),         (19, ’9165 laburnum St,   Darnall Ward  Yorkshire, South     UK’,‘S4 7WN’)       insert into @IncorrectRows(Address_ID,TheAddress, ThePostcode)        SELECT Address_ID,TheAddress,ThePostCode FROM dbo.ExtractPostcode(@InputTable)       EXCEPT     SELECT Address_ID,TheAddress,ThePostCode FROM @outputTable; If @@RowCount>0        Begin        PRINT ‘The following rows gave ‘;     SELECT Address_ID,TheAddress,ThePostCode FROM @IncorrectRows        RAISERROR (‘These rows gave unexpected results.’,16,1);     end   /* For tear-down, we drop the user defined table type */ IF EXISTS(SELECT * FROM sys.types WHERE name LIKE ‘OutputFormat’                                    and schema_name(schema_ID)=‘Dbo’)   DROP TYPE dbo.OutputFormat GO /* once this is working, the development work turns from a chore into a delight and one ends up hitting execute so much more often to catch mistakes as soon as possible. It also prevents a wildly-broken routine getting into a build! */

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• BizTalk: History of one project architecture

  - by Leonid Ganeline

  "In the beginning God made heaven and earth. Then he started to integrate." At the very start was the requirement: integrate two working systems. Small digging up: It was one system. It was good but IT guys want to change it to the new one, much better, chipper, more flexible, and more progressive in technologies, more suitable for the future, for the faster world and hungry competitors. One thing. One small, little thing. We cannot turn off the old system (call it A, because it was the first), turn on the new one (call it B, because it is second but not the last one). The A has a hundreds users all across a country, they must study B. A still has a lot nice custom features, home-made features that cannot disappear. These features have to be moved to the B and it is a long process, months and months of redevelopment. So, the decision was simple. Let’s move not jump, let’s both systems working side-by-side several months. In this time we could teach the users and move all custom A’s special functionality to B. That automatically means both systems should work side-by-side all these months and use the same data. Data in A and B must be in sync. That’s how the integration projects get birth. Moreover, the specific of the user tasks requires the both systems must be in sync in real-time. Nightly synchronization is not working, absolutely.   First draft The first draft seems simple. Both systems keep data in SQL databases. When data changes, the Create, Update, Delete operations performed on the data, and the sync process could be started. The obvious decision is to use triggers on tables. When we are talking about data, we are talking about several entities. For example, Orders and Items [in Orders]. We decided to use the BizTalk Server to synchronize systems. Why it was chosen is another story. Second draft   Let’s take an example how it works in more details. 1.       User creates a new entity in the A system. This fires an insert trigger on the entity table. Trigger has to pass the message “Entity created”. This message includes all attributes of the new entity, but I focused on the Id of this entity in the A system. Notation for this message is id.A. System A sends id.A to the BizTalk Server. 2.       BizTalk transforms id.A to the format of the system B. This is easiest part and I will not focus on this kind of transformations in the following text. The message on the picture is still id.A but it is in slightly different format, that’s why it is changing in color. BizTalk sends id.A to the system B. 3.       The system B creates the entity on its side. But it uses different id-s for entities, these id-s are id.B. System B saves id.A+id.B. System B sends the message id.A+id.B back to the BizTalk. 4.       BizTalk sends the message id.A+id.B to the system A. 5.       System A saves id.A+id.B. Why both id-s should be saved on both systems? It was one of the next requirements. Users of both systems have to know the systems are in sync or not in sync. Users working with the entity on the system A can see the id.B and use it to switch to the system B and work there with the copy of the same entity. The decision was to store the pairs of entity id-s on both sides. If there is only one id, the entities are not in sync yet (for the Create operation). Third draft Next problem was the reliability of the synchronization. The synchronizing process can be interrupted on each step, when message goes through the wires. It can be communication problem, timeout, temporary shutdown one of the systems, the second system cannot be synchronized by some internal reason. There were several potential problems that prevented from enclosing the whole synchronization process in one transaction. Decision was to restart the whole sync process if it was not finished (in case of the error). For this purpose was created an additional service. Let’s call it the Resync service. We still keep the id pairs in both systems, but only for the fast access not for the synchronization process. For the synchronizing these id-s now are kept in one main place, in the Resync service database. The Resync service keeps record as: ·       Id.A ·       Id.B ·       Entity.Type ·       Operation (Create, Update, Delete) ·       IsSyncStarted (true/false) ·       IsSyncFinished (true/false0 The example now looks like: 1.       System A creates id.A. id.A is saved on the A. Id.A is sent to the BizTalk. 2.       BizTalk sends id.A to the Resync and to the B. id.A is saved on the Resync. 3.       System B creates id.B. id.A+id.B are saved on the B. id.A+id.B are sent to the BizTalk. 4.       BizTalk sends id.A+id.B to the Resync and to the A. id.A+id.B are saved on the Resync. 5.       id.A+id.B are saved on the B. Resync changes the IsSyncStarted and IsSyncFinished flags accordingly. The Resync service implements three main methods: ·       Save (id.A, Entity.Type, Operation) ·       Save (id.A, id.B, Entity.Type, Operation) ·       Resync () Two Save() are used to save id-s to the service storage. See in the above example, in 2 and 4 steps. What about the Resync()? It is the method that finishes the interrupted synchronization processes. If Save() is started by the trigger event, the Resync() is working as an independent process. It periodically scans the Resync storage to find out “unfinished” records. Then it restarts the synchronization processes. It tries to synchronize them several times then gives up.     One more thing, both systems A and B must tolerate duplicates of one synchronizing process. Say on the step 3 the system B was not able to send id.A+id.B back. The Resync service must restart the synchronization process that will send the id.A to B second time. In this case system B must just send back again also created id.A+id.B pair without errors. That means “tolerate duplicates”. Fourth draft Next draft was created only because of the aesthetics. As it always happens, aesthetics gave significant performance gain to the whole system. First was the stupid question. Why do we need this additional service with special database? Can we just master the BizTalk to do something like this Resync() does? So the Resync orchestration is doing the same thing as the Resync service. It is started by the Id.A and finished by the id.A+id.B message. The first works as a Start message, the second works as a Finish message.     Here is a diagram the whole process without errors. It is pretty straightforward. The Resync orchestration is waiting for the Finish message specific period of time then resubmits the Id.A message. It resubmits the Id.A message specific number of times then gives up and gets suspended. It can be resubmitted then it starts the whole process again: waiting [, resubmitting [, get suspended]], finishing. Tuning up The Resync orchestration resubmits the id.A message with special “Resubmitted” flag. The subscription filter on the Resync orchestration includes predicate as (Resubmit_Flag != “Resubmitted”). That means only the first Sync orchestration starts the Resync orchestration. Other Sync orchestration instantiated by the resubmitting can finish this Resync orchestration but cannot start another instance of the Resync   Here is a diagram where system B was inaccessible for some period of time. The Resync orchestration resubmitted the id.A two times. Then system B got the response the id.A+id.B and this finished the Resync service execution. What is interesting about this, there were submitted several identical id.A messages and only one id.A+id.B message. Because of this, the system B and the Resync must tolerate the duplicate messages. We also told about this requirement for the system B. Now the same requirement is for the Resunc. Let’s assume the system B was very slow in the first response and the Resync service had time to resubmit two id.A messages. System B responded not, as it was in previous case, with one id.A+id.B but with two id.A+id.B messages. First of them finished the Resync execution for the id.A. What about the second id.A+id.B? Where it goes? So, we have to add one more internal requirement. The whole solution must tolerate many identical id.A+id.B messages. It is easy task with the BizTalk. I added the “SinkExtraMessages” subscriber (orchestration with one receive shape), that just get these messages and do nothing. Real design Real architecture is much more complex and interesting. In reality each system can submit several id.A almost simultaneously and completely unordered. There are not only the “Create entity” operation but the Update and Delete operations. And these operations relate each other. Say the Update operation after Delete means not the same as Update after Create. In reality there are entities related each other. Say the Order and Order Items. Change on one of it could start the series of the operations on another. Moreover, the system internals are the “black boxes” and we cannot predict the exact content and order of the operation series. It worth to say, I had to spend a time to manage the zombie message problems. The zombies are still here, but this is not a problem now. And this is another story. What is interesting in the last design? One orchestration works to help another to be more reliable. Why two orchestration design is more reliable, isn’t it something strange? The Synch orchestration takes all the message exchange between systems, here is the area where most of the errors could happen. The Resync orchestration sends and receives messages only within the BizTalk server. Is there another design? Sure. All Resync functionality could be implemented inside the Sync orchestration. Hey guys, some other ideas?

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• Maintaining State in Mud Engine

  - by Johnathon Sullinger

  I am currently working on a Mud Engine and have started implementing my state engine. One of the things that has me troubled is maintaining different states at once. For instance, lets say that the user has started a tutorial, which requires specific input. If the user types "help" I want to switch in to a help state, so they can get the help they need, then return them to the original state once exiting the help. my state system uses a State Manager to manage the state per user: public class StateManager { /// <summary> /// Gets the current state. /// </summary> public IState CurrentState { get; private set; } /// <summary> /// Gets the states available for use. /// </summary> /// <value> public List<IState> States { get; private set; } /// <summary> /// Gets the commands available. /// </summary> public List<ICommand> Commands { get; private set; } /// <summary> /// Gets the mob that this manager controls the state of. /// </summary> public IMob Mob { get; private set; } public void Initialize(IMob mob, IState initialState = null) { this.Mob = mob; if (initialState != null) { this.SwitchState(initialState); } } /// <summary> /// Performs the command. /// </summary> /// <param name="message">The message.</param> public void PerformCommand(IMessage message) { if (this.CurrentState != null) { ICommand command = this.CurrentState.GetCommand(message); if (command is NoOpCommand) { // NoOperation commands indicate that the current state is not finished yet. this.CurrentState.Render(this.Mob); } else if (command != null) { command.Execute(this.Mob); } else if (command == null) { new InvalidCommand().Execute(this.Mob); } } } /// <summary> /// Switches the state. /// </summary> /// <param name="state">The state.</param> public void SwitchState(IState state) { if (this.CurrentState != null) { this.CurrentState.Cleanup(); } this.CurrentState = state; if (state != null) { this.CurrentState.Render(this.Mob); } } } Each of the different states that the user can be in, is a Type implementing IState. public interface IState { /// <summary> /// Renders the current state to the players terminal. /// </summary> /// <param name="player">The player to render to</param> void Render(IMob mob); /// <summary> /// Gets the Command that the player entered and preps it for execution. /// </summary> /// <returns></returns> ICommand GetCommand(IMessage command); /// <summary> /// Cleanups this instance during a state change. /// </summary> void Cleanup(); } Example state: public class ConnectState : IState { /// <summary> /// The connected player /// </summary> private IMob connectedPlayer; public void Render(IMob mob) { if (!(mob is IPlayer)) { throw new NullReferenceException("ConnectState can only be used with a player object implementing IPlayer"); } //Store a reference for the GetCommand() method to use. this.connectedPlayer = mob as IPlayer; var server = mob.Game as IServer; var game = mob.Game as IGame; // It is not guaranteed that mob.Game will implement IServer. We are only guaranteed that it will implement IGame. if (server == null) { throw new NullReferenceException("LoginState can only be set to a player object that is part of a server."); } //Output the game information mob.Send(new InformationalMessage(game.Name)); mob.Send(new InformationalMessage(game.Description)); mob.Send(new InformationalMessage(string.Empty)); //blank line //Output the server MOTD information mob.Send(new InformationalMessage(string.Join("\n", server.MessageOfTheDay))); mob.Send(new InformationalMessage(string.Empty)); //blank line mob.StateManager.SwitchState(new LoginState()); } /// <summary> /// Gets the command. /// </summary> /// <param name="message">The message.</param> /// <returns>Returns no operation required.</returns> public Commands.ICommand GetCommand(IMessage message) { return new NoOpCommand(); } /// <summary> /// Cleanups this instance during a state change. /// </summary> public void Cleanup() { // We have nothing to clean up. return; } } With the way that I have my FSM set up at the moment, the user can only ever have one state at a time. I read a few different posts on here about state management but nothing regarding keeping a stack history. I thought about using a Stack collection, and just pushing new states on to the stack then popping them off as the user moves out from one. It seems like it would work, but I'm not sure if it is the best approach to take. I'm looking for recommendations on this. I'm currently swapping state from within the individual states themselves as well which I'm on the fence about if it makes sense to do there or not. The user enters a command, the StateManager passes the command to the current State and lets it determine if it needs it (like passing in a password after entering a user name), if the state doesn't need any further commands, it returns null. If it does need to continue doing work, it returns a No Operation to let the state manager know that the state still requires further input from the user. If null is returned, the state manager will then go find the appropriate state for the command entered by the user. Example state requiring additional input from the user public class LoginState : IState { /// <summary> /// The connected player /// </summary> private IPlayer connectedPlayer; private enum CurrentState { FetchUserName, FetchPassword, InvalidUser, } private CurrentState currentState; /// <summary> /// Renders the current state to the players terminal. /// </summary> /// <param name="mob"></param> /// <exception cref="System.NullReferenceException"> /// ConnectState can only be used with a player object implementing IPlayer /// or /// LoginState can only be set to a player object that is part of a server. /// </exception> public void Render(IMob mob) { if (!(mob is IPlayer)) { throw new NullReferenceException("ConnectState can only be used with a player object implementing IPlayer"); } //Store a reference for the GetCommand() method to use. this.connectedPlayer = mob as IPlayer; var server = mob.Game as IServer; // Register to receive new input from the user. mob.ReceivedMessage += connectedPlayer_ReceivedMessage; if (server == null) { throw new NullReferenceException("LoginState can only be set to a player object that is part of a server."); } this.currentState = CurrentState.FetchUserName; switch (this.currentState) { case CurrentState.FetchUserName: mob.Send(new InputMessage("Please enter your user name")); break; case CurrentState.FetchPassword: mob.Send(new InputMessage("Please enter your password")); break; case CurrentState.InvalidUser: mob.Send(new InformationalMessage("Invalid username/password specified.")); this.currentState = CurrentState.FetchUserName; mob.Send(new InputMessage("Please enter your user name")); break; } } /// <summary> /// Receives the players input. /// </summary> /// <param name="sender">The sender.</param> /// <param name="e">The e.</param> void connectedPlayer_ReceivedMessage(object sender, IMessage e) { // Be good memory citizens and clean ourself up after receiving a message. // Not doing this results in duplicate events being registered and memory leaks. this.connectedPlayer.ReceivedMessage -= connectedPlayer_ReceivedMessage; ICommand command = this.GetCommand(e); } /// <summary> /// Gets the Command that the player entered and preps it for execution. /// </summary> /// <param name="command"></param> /// <returns>Returns the ICommand specified.</returns> public Commands.ICommand GetCommand(IMessage command) { if (this.currentState == CurrentState.FetchUserName) { this.connectedPlayer.Name = command.Message; this.currentState = CurrentState.FetchPassword; } else if (this.currentState == CurrentState.FetchPassword) { // find user } return new NoOpCommand(); } /// <summary> /// Cleanups this instance during a state change. /// </summary> public void Cleanup() { // If we have a player instance, we clean up the registered event. if (this.connectedPlayer != null) { this.connectedPlayer.ReceivedMessage -= this.connectedPlayer_ReceivedMessage; } } Maybe my entire FSM isn't wired up in the best way, but I would appreciate input on what would be the best to maintain a stack of state in a MUD game engine, and if my states should be allowed to receive the input from the user or not to check what command was entered before allowing the state manager to switch states. Thanks in advance.

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• CodePlex Daily Summary for Monday, July 22, 2013

  CodePlex Daily Summary for Monday, July 22, 2013Popular ReleasesAndroidCopyAndPaste: Capood: Erstes Release für Evaluation --> Changeset 26675fastJSON: v2.0.17: 2.0.17 - added serialization of static fields and properties - added dynamic object support and testKartris Ecommerce ASP.NET Shopping Cart: Kartris v2.5002: This is the release version of Kartris with the responsive interface based on Zurb's Foundation framework. It will work on any screen size, down to and including mobile devices such as the iphone. We've also fixed issues with Apple iOS products being treated by ASP.NET as 'downscale' devices, which broke some functionality in Kartris. This release also includes native Bitcoin support (no third party services required - it communicates directly with the standard Bitcoin client via a JSON API)...VG-Ripper & PG-Ripper: PG-Ripper 1.4.15: changes NEW: Added Support for "ImgChili.net" links NEW: Added Support for "ImgBabes.com" linksAcDown?????: AcDown????? v4.4.3: ??●AcDown??????????、??、??、???????。????，????，?????????????????????????。???????????Acfun、????(Bilibili)、??、??、YouTube、??、???、??????、SF????、????????????。 ●??????AcPlay?????，??????、????????????????。 ● AcDown???????C#??，????.NET Framework 2.0??。?????"Acfun?????"。 ??v4.4.3 ?? ??Bilibili????????????? ???????????? ????32??64? Windows XP/Vista/7/8 ???? 32??64? ???Linux ????(1)????????Windows XP???，????????.NET Framework 2.0???(x86)，?????"?????????"??? (2)???????????Linux???，????????Mono?? ??2.10?...Magick.NET: Magick.NET 6.8.6.601: Magick.NET linked with ImageMagick 6.8.6.6. These zip files are also available as a NuGet package: https://nuget.org/profiles/dlemstra/MISAO: Ver. 5.33: Latest app and add-insC# Intellisense for Notepad++: Initial release: Members auto-complete Integration with native Notepad++ Auto-Completion Auto "open bracket" for methods Right-arrow to accept suggestions51Degrees.mobi - Mobile Device Detection and Redirection: 2.1.19.4: One Click Install from NuGet This release introduces the 51Degrees.mobi IIS Vary Header Fix. When Compression and Caching is used in IIS, the Vary header is overwritten, making intelligent caching with dynamic content impossible. Find out more about installing the Vary Header fix. Changes to Version 2.1.19.4Handlers now have a ‘Count’ property. This is an integer value that shows how many devices in the dataset that use that handler. Provider.cs -> GetDeviceInfoByID to address a problem w...SalarDbCodeGenerator: SalarDbCodeGenerator v2.1.2013.0719: Version 2.1.2013.0719 2013/7/19 Pattern Changes: * DapperContext pattern is added. * All patterns are updated to work with one-to-one relations. Changes: * One-to-one relation is supported. * Minor bug fixes..NET Code Migrator for Dynamics CRM: v1.0.12: Combined the main macros, generated macros from a sample organization, and the CreateVisualStudioMacros utility into a single package.DARF: Dynamic Application Runtime Framework: DARF.Demo: This demo is DARF.IDE application plus a sample file (calculator.xda) which describes a very simple calculator. All you need to do is to unzip the package, run DARF.IDE.exe and load calculator.xda then press F5 or select 'Execute' from 'Code' menu to see the execution of the application. The calculator.xda file is fully commented so you can inspect the file and get a feeling of the way DARF works. This sample application makes use of some pre-written blocks (namely button, textbox and ...) ...Player Framework by Microsoft: Player Framework for Windows and WP (v1.3 beta 2): Includes all changes in v1.3 beta 1 Additional support for Windows 8.1 Preview New API (JS): addTextTrack New API (JS): msKeys New API (JS): msPlayToPreferredSourceUri New API (JS): msSetMediaKeys New API (JS): onmsneedkey New API (Xaml): SetMediaStreamSource method New API (Xaml): Stretch property New API (Xaml): StretchChanged event New API (Xaml): AreTransportControlsEnabled property New API (Xaml): IsFullWindow property New API (Xaml): PlayToPreferredSourceUri proper...CodeGen Code Generator: CodeGen 4.2.11: Changes in this release include: Added several new alternate forms of the <FIELD_SELWND> token to provide template developers better control over the case of field selection window names. Also added a new token <FIELD_SELWND_ORIGINAL> to preserve the case of selection window names in the same way that <FIELD_SELWND> used to. Enhanced UI Toolkit window script selection window processing (-ws) so that selection window names are no longer case sensitive (they aren't in UI Toolkit). Also the -w...Outlook 2013 Add-In: Multiple Calendars: As per popular request, this new version includes: - Support for multiple calendars. This can be enabled in the configuration by choosing which ones to show/hide appointments from. In some cases (public folders) it may time out and crash, and so far it only supports "My Calendars", so not shared ones yet. Also they're currently shown in the same font/color so there are no confusions with color categories, but please drop me a line on any suggestions you'd like to see implemented. - Added fri...Circuit Diagram: Circuit Diagram 2.0 Beta 2: New in this release: Show grid in editor Cut/copy/paste support Bug fixesOrchard Project: Orchard 1.7 RC: Planning releasedTerminals: Version 3.1 - Release: Changes since version 3.0:15992 Unified usage of icons in user interface Added context menu in Organize favorites grid Fixed:34219 34210 34223 33981 34209 Install notes:No changes in database (use database from release 3.0) No upgrade of configuration, passwords, credentials or favorites See also upgrade notes for release 3.0Media Companion: Media Companion MC3.573b: XBMC Link - Let MC update your XBMC Library Fixes in place, Enjoy the XBMC Link function Well, Phil's been busy in the background, and come up with a Great new feature for Media Companion. Currently only implemented for movies. Once we're happy that's working with no issues, we'll extend the functionality to include TV shows. All the help for this is build into the application. Go to General Preferences - XBMC Link for details. Help us make it better* Currently only tested on local and ...Wsus Package Publisher: Release v1.2.1307.15: Fix a bug where WPP crash if 'ShowPendingUpdates' is start with wrong credentials. Fix a bug where WPP crash if ArrivalDateAfter and ArrivalDateBefore is equal in the ComputerView. Add a filter in the ComputerView. (Thanks to NorbertFe for this feature request) Add an option, when right-clicking on a computer, you can ask for display the current logon user of the remote computer. Add an option in settings to choose if WPP ping remote computers using IPv4, IPv6 or IPv6 and, if fail, IP...New ProjectsAssociativy Tag Nodes: Lightweight Associativy nodes that behave somewhat like tags.CESQLite2013: SQLite for Windows Embedded Compact 2013: A project to provide SQLite.dll for x86 Windows Embedded Compact 2013cmsserver: ????，HTTP??DDRMenu Extension for Ventrian Simple Gallery: The aim of this project is to include inside the DDRMenu all the gallery availables as subitem of the page they are onto.Devanagari Keyboard: Windows Marathi, Devanagari Keyboard Software by Nitin SawantFastMessages. MSG.Exe Alternative. Easily send messages to desktop: Easily send messages to desktop. A simple command (FastMessage.exe) acts as an alternative to MSG.EXE into scripts. Destinations can be domain users or groups.GameTools: ??????，?????????Memory Teaser Game: It is a game written in C sharp .NET version 4.5.RegEdit for Windows Embedded Compact (Windows CE): Registry editor for Windows Embedded Compact (Windows CE).Scripter: Scripter is designed to handle client side activities consumed by a websiteStartingwithServiceBusCSharp: this project is a very basic introduction to start developing using Windows Azure Service Bus using Brokered, queue messaging.Team 2 Collaboration: Whaddup!VM Project Generator Release: Generator Abrevieri Viorel MadaWatcher Orchard module: Orchard module for watching content items and geting notified on modifications.Workout Tracker: Simple workout tracker.zendigh php framework: zendigh is open source php framework to create high traffic websites.

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• Negamax implementation doesn't appear to work with tic-tac-toe

  - by George Jiglau

  I've implemented Negamax as it can be found on wikipedia, which includes alpha/beta pruning. However, it seems to favor a losing move, which should be an invalid result. The game is Tic-Tac-Toe, I've abstracted most of the game play so it should be rather easy to spot an error within the algorithm. Here is the code, nextMove, negamax or evaluate are probably the functions that contain the fault: #include <list> #include <climits> #include <iostream> //#define DEBUG 1 using namespace std; struct Move { int row, col; Move(int row, int col) : row(row), col(col) { } Move(const Move& m) { row = m.row; col = m.col; } }; struct Board { char player; char opponent; char board[3][3]; Board() { } void read(istream& stream) { stream >> player; opponent = player == 'X' ? 'O' : 'X'; for(int row = 0; row < 3; row++) { for(int col = 0; col < 3; col++) { char playa; stream >> playa; board[row][col] = playa == '_' ? 0 : playa == player ? 1 : -1; } } } void print(ostream& stream) { for(int row = 0; row < 3; row++) { for(int col = 0; col < 3; col++) { switch(board[row][col]) { case -1: stream << opponent; break; case 0: stream << '_'; break; case 1: stream << player; break; } } stream << endl; } } void do_move(const Move& move, int player) { board[move.row][move.col] = player; } void undo_move(const Move& move) { board[move.row][move.col] = 0; } bool isWon() { if (board[0][0] != 0) { if (board[0][0] == board[0][1] && board[0][1] == board[0][2]) return true; if (board[0][0] == board[1][0] && board[1][0] == board[2][0]) return true; } if (board[2][2] != 0) { if (board[2][0] == board[2][1] && board[2][1] == board[2][2]) return true; if (board[0][2] == board[1][2] && board[1][2] == board[2][2]) return true; } if (board[1][1] != 0) { if (board[0][1] == board[1][1] && board[1][1] == board[2][1]) return true; if (board[1][0] == board[1][1] && board[1][1] == board[1][2]) return true; if (board[0][0] == board[1][1] && board[1][1] == board[2][2]) return true; if (board[0][2] == board [1][1] && board[1][1] == board[2][0]) return true; } return false; } list<Move> getMoves() { list<Move> moveList; for(int row = 0; row < 3; row++) for(int col = 0; col < 3; col++) if (board[row][col] == 0) moveList.push_back(Move(row, col)); return moveList; } }; ostream& operator<< (ostream& stream, Board& board) { board.print(stream); return stream; } istream& operator>> (istream& stream, Board& board) { board.read(stream); return stream; } int evaluate(Board& board) { int score = board.isWon() ? 100 : 0; for(int row = 0; row < 3; row++) for(int col = 0; col < 3; col++) if (board.board[row][col] == 0) score += 1; return score; } int negamax(Board& board, int depth, int player, int alpha, int beta) { if (board.isWon() || depth <= 0) { #if DEBUG > 1 cout << "Found winner board at depth " << depth << endl; cout << board << endl; #endif return player * evaluate(board); } list<Move> allMoves = board.getMoves(); if (allMoves.size() == 0) return player * evaluate(board); for(list<Move>::iterator it = allMoves.begin(); it != allMoves.end(); it++) { board.do_move(*it, -player); int val = -negamax(board, depth - 1, -player, -beta, -alpha); board.undo_move(*it); if (val >= beta) return val; if (val > alpha) alpha = val; } return alpha; } void nextMove(Board& board) { list<Move> allMoves = board.getMoves(); Move* bestMove = NULL; int bestScore = INT_MIN; for(list<Move>::iterator it = allMoves.begin(); it != allMoves.end(); it++) { board.do_move(*it, 1); int score = -negamax(board, 100, 1, INT_MIN + 1, INT_MAX); board.undo_move(*it); #if DEBUG cout << it->row << ' ' << it->col << " = " << score << endl; #endif if (score > bestScore) { bestMove = &*it; bestScore = score; } } if (!bestMove) return; cout << bestMove->row << ' ' << bestMove->col << endl; #if DEBUG board.do_move(*bestMove, 1); cout << board; #endif } int main() { Board board; cin >> board; #if DEBUG cout << "Starting board:" << endl; cout << board; #endif nextMove(board); return 0; } Giving this input: O X__ ___ ___ The algorithm chooses to place a piece at 0, 1, causing a guaranteed loss, do to this trap(nothing can be done to win or end in a draw): XO_ X__ ___ Perhaps it has something to do with the evaluation function? If so, how could I fix it?

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• How to deal with malicious domain redirections?

  - by user359650

  It is possible for anybody to buy a domain name containing negative terms and point it to someone's website in order to damage their reputation. For instance someone could buy the domain child-pornography.com and point it to the address 64.34.119.12 which is the address behind stackoverflow.com and people navigating to the domain in question would end up visualizing content from StackExchange which would be detrimental to StackExchange's image. To illustrate this, I added the entry 64.34.119.12 child-pornography.com to my /etc/hosts file and tested. Here is what I obtained: I personally found this user experience terrible as someone could think that Stack Exchange are in favor of child pornography and awaiting support from the community to create a Q&A site about it. I tested with other websites and experienced other behaviors that I would categorize as follows: 1 - Useful 404 page (happens with stackoverflow.com): For me the worst way of handling this as the image of the targeted website is directly associated with the offending domain. The more useful the 404 page, the bigger the impression that the targeted website would be willing to help with child pornography. 2 - Redirection (happens with microsoft.com): For instance when accessing child-pornography.com you get redirected to www.microsoft.com. It isn't as bad as above as the offending domain name never appears alongside the targeted website's content, but still bad in my opinion as it gives the impression the targeted website bought the offending domain and redirected it to their website to get more traffic. 3 - Server error (happens with lemonde.fr): You get an error from the webserver which page doesn't contain any content that can be associated with the targeted website (e.g. default Apache 404 page, completely blank page). I believe that is good as the identify of the targeted website isn't revealed. Above are the various behaviors I experienced, but I also thought about a fourth way of dealing with this which is described below. 4 - Disclaimer page (haven't found any website implementing that technique): Display a message such as : "You ended here because someone bought and linked the child-pornography.com domain to our website. We do not own this domain and do not associate ourselves with it. This request has been logged by our servers and we will raise this issue with the competent authorities to have this domain taken down. If you want to access our website, please click here." The good thing about this method is that it can be implemented at application layer (good if you don't have control over web server which happens with some hosting solutions), allows you to protect yourself from any liability, and offer the visitor to be redirected to your own website. Which of the above options would you implement to deal with malicious domain linking (IMO only options 3 and 4 are worth considering) ?

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• When someone deletes a shared data source in SSRS

  - by Rob Farley

  SQL Server Reporting Services plays nicely. You can have things in the catalogue that get shared. You can have Reports that have Links, Datasets that can be used across different reports, and Data Sources that can be used in a variety of ways too. So if you find that someone has deleted a shared data source, you potentially have a bit of a horror story going on. And this works for this month’s T-SQL Tuesday theme, hosted by Nick Haslam, who wants to hear about horror stories. I don’t write about LobsterPot client horror stories, so I’m writing about a situation that a fellow MVP friend asked me about recently instead. The best thing to do is to grab a recent backup of the ReportServer database, restore it somewhere, and figure out what’s changed. But of course, this isn’t always possible. And it’s much nicer to help someone with this kind of thing, rather than to be trying to fix it yourself when you’ve just deleted the wrong data source. Unfortunately, it lets you delete data sources, without trying to scream that the data source is shared across over 400 reports in over 100 folders, as was the case for my friend’s colleague. So, suddenly there’s a big problem – lots of reports are failing, and the time to turn it around is small. You probably know which data source has been deleted, but getting the shared data source back isn’t the hard part (that’s just a connection string really). The nasty bit is all the re-mapping, to get those 400 reports working again. I know from exploring this kind of stuff in the past that the ReportServer database (using its default name) has a table called dbo.Catalog to represent the catalogue, and that Reports are stored here. However, the information about what data sources these deployed reports are configured to use is stored in a different table, dbo.DataSource. You could be forgiven for thinking that shared data sources would live in this table, but they don’t – they’re catalogue items just like the reports. Let’s have a look at the structure of these two tables (although if you’re reading this because you have a disaster, feel free to skim past). Frustratingly, there doesn’t seem to be a Books Online page for this information, sorry about that. I’m also not going to look at all the columns, just ones that I find interesting enough to mention, and that are related to the problem at hand. These fields are consistent all the way through to SQL Server 2012 – there doesn’t seem to have been any changes here for quite a while. dbo.Catalog The Primary Key is ItemID. It’s a uniqueidentifier. I’m not going to comment any more on that. A minor nice point about using GUIDs in unfamiliar databases is that you can more easily figure out what’s what. But foreign keys are for that too… Path, Name and ParentID tell you where in the folder structure the item lives. Path isn’t actually required – you could’ve done recursive queries to get there. But as that would be quite painful, I’m more than happy for the Path column to be there. Path contains the Name as well, incidentally. Type tells you what kind of item it is. Some examples are 1 for a folder and 2 a report. 4 is linked reports, 5 is a data source, 6 is a report model. I forget the others for now (but feel free to put a comment giving the full list if you know it). Content is an image field, remembering that image doesn’t necessarily store images – these days we’d rather use varbinary(max), but even in SQL Server 2012, this field is still image. It stores the actual item definition in binary form, whether it’s actually an image, a report, whatever. LinkSourceID is used for Linked Reports, and has a self-referencing foreign key (allowing NULL, of course) back to ItemID. Parameter is an ntext field containing XML for the parameters of the report. Not sure why this couldn’t be a separate table, but I guess that’s just the way it goes. This field gets changed when the default parameters get changed in Report Manager. There is nothing in dbo.Catalog that describes the actual data sources that the report uses. The default data sources would be part of the Content field, as they are defined in the RDL, but when you deploy reports, you typically choose to NOT replace the data sources. Anyway, they’re not in this table. Maybe it was already considered a bit wide to throw in another ntext field, I’m not sure. They’re in dbo.DataSource instead. dbo.DataSource The Primary key is DSID. Yes it’s a uniqueidentifier... ItemID is a foreign key reference back to dbo.Catalog Fields such as ConnectionString, Prompt, UserName and Password do what they say on the tin, storing information about how to connect to the particular source in question. Link is a uniqueidentifier, which refers back to dbo.Catalog. This is used when a data source within a report refers back to a shared data source, rather than embedding the connection information itself. You’d think this should be enforced by foreign key, but it’s not. It does allow NULLs though. Flags this is an int, and I’ll come back to this. When a Data Source gets deleted out of dbo.Catalog, you might assume that it would be disallowed if there are references to it from dbo.DataSource. Well, you’d be wrong. And not because of the lack of a foreign key either. Deleting anything from the catalogue is done by calling a stored procedure called dbo.DeleteObject. You can look at the definition in there – it feels very much like the kind of Delete stored procedures that many people write, the kind of thing that means they don’t need to worry about allowing cascading deletes with foreign keys – because the stored procedure does the lot. Except that it doesn’t quite do that. If it deleted everything on a cascading delete, we’d’ve lost all the data sources as configured in dbo.DataSource, and that would be bad. This is fine if the ItemID from dbo.DataSource hooks in – if the report is being deleted. But if a shared data source is being deleted, you don’t want to lose the existence of the data source from the report. So it sets it to NULL, and it marks it as invalid. We see this code in that stored procedure. UPDATE [DataSource]    SET       [Flags] = [Flags] & 0x7FFFFFFD, -- broken link       [Link] = NULL FROM    [Catalog] AS C    INNER JOIN [DataSource] AS DS ON C.[ItemID] = DS.[Link] WHERE    (C.Path = @Path OR C.Path LIKE @Prefix ESCAPE '*') Unfortunately there’s no semi-colon on the end (but I’d rather they fix the ntext and image types first), and don’t get me started about using the table name in the UPDATE clause (it should use the alias DS). But there is a nice comment about what’s going on with the Flags field. What I’d LIKE it to do would be to set the connection information to a report-embedded copy of the connection information that’s in the shared data source, the one that’s about to be deleted. I understand that this would cause someone to lose the benefit of having the data sources configured in a central point, but I’d say that’s probably still slightly better than LOSING THE INFORMATION COMPLETELY. Sorry, rant over. I should log a Connect item – I’ll put that on my todo list. So it sets the Link field to NULL, and marks the Flags to tell you they’re broken. So this is your clue to fixing it. A bitwise AND with 0x7FFFFFFD is basically stripping out the ‘2’ bit from a number. So numbers like 2, 3, 6, 7, 10, 11, etc, whose binary representation ends in either 11 or 10 get turned into 0, 1, 4, 5, 8, 9, etc. We can test for it using a WHERE clause that matches the SET clause we’ve just used. I’d also recommend checking for Link being NULL and also having no ConnectionString. And join back to dbo.Catalog to get the path (including the name) of broken reports are – in case you get a surprise from a different data source being broken in the past. SELECT c.Path, ds.Name FROM dbo.[DataSource] AS ds JOIN dbo.[Catalog] AS c ON c.ItemID = ds.ItemID WHERE ds.[Flags] = ds.[Flags] & 0x7FFFFFFD AND ds.[Link] IS NULL AND ds.[ConnectionString] IS NULL; When I just ran this on my own machine, having deleted a data source to check my code, I noticed a Report Model in the list as well – so if you had thought it was just going to be reports that were broken, you’d be forgetting something. So to fix those reports, get your new data source created in the catalogue, and then find its ItemID by querying Catalog, using Path and Name to find it. And then use this value to fix them up. To fix the Flags field, just add 2. I prefer to use bitwise OR which should do the same. Use the OUTPUT clause to get a copy of the DSIDs of the ones you’re changing, just in case you need to revert something later after testing (doing it all in a transaction won’t help, because you’ll just lock out the table, stopping you from testing anything). UPDATE ds SET [Flags] = [Flags] | 2, [Link] = '3AE31CBA-BDB4-4FD1-94F4-580B7FAB939D' /*Insert your own GUID*/ OUTPUT deleted.Name, deleted.DSID, deleted.ItemID, deleted.Flags FROM dbo.[DataSource] AS ds JOIN dbo.[Catalog] AS c ON c.ItemID = ds.ItemID WHERE ds.[Flags] = ds.[Flags] & 0x7FFFFFFD AND ds.[Link] IS NULL AND ds.[ConnectionString] IS NULL; But please be careful. Your mileage may vary. And there’s no reason why 400-odd broken reports needs to be quite the nightmare that it could be. Really, it should be less than five minutes. @rob_farley

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• CodePlex Daily Summary for Thursday, July 25, 2013

  CodePlex Daily Summary for Thursday, July 25, 2013Popular ReleasesEnglish Practice Helper: English Practice Helper Demo v1.0: The first demoTweetinvi a friendly C# Twitter API: Alpha 0.8.0.1: This is the first release of Tweetinvi. Please report any issue in the discussion or issues. Sincerely, LinviKartris E-commerce: Kartris v2.5003: This fixes an issue where search engines appear to identify as IE and so trigger the noIE page if there is not a non-responsive skin specified.VG-Ripper & PG-Ripper: VG-Ripper 2.9.45: changes NEW: Added Support for "ImgBabes.com" links NEW: Added Support for "ImagesIon.com" linksMagelia WebStore Open-source Ecommerce software: Magelia WebStore 2.4: Magelia WebStore version 2.4 introduces new and improved features: Basket and order calculation have been redesigned with a more modular approach geographic zone algorithms for tax and shipping calculations have been re-developed. The Store service has been split in three services (store, basket, order). Product start and end dates have been added. For variant products a unique code has been introduced for the top (variable) product, product attributes can now be defined at the top ...LogicCircuit: LogicCircuit 2.13.07.22: Logic Circuit - is educational software for designing and simulating logic circuits. Intuitive graphical user interface, allows you to create unrestricted circuit hierarchy with multi bit buses, debug circuits behavior with oscilloscope, and navigate running circuits hierarchy. Changes of this versionYou can make visual elements of the circuit been visible on its symbols. This way you can build composite displays, keyboards and reuse them. Please read about displays for more details http://ww...LINQ to Twitter: LINQ to Twitter v2.1.08: Supports .NET 3.5, .NET 4.0, .NET 4.5, Silverlight 4.0, Windows Phone 7.1, Windows Phone 8, Client Profile, Windows 8, and Windows Azure. 100% Twitter API coverage. Also supports Twitter API v1.1! Also on NuGet.AcDown?????: AcDown????? v4.4.3: ??●AcDown??????????、??、??、???????。????，????，?????????????????????????。???????????Acfun、????(Bilibili)、??、??、YouTube、??、???、??????、SF????、????????????。 ●??????AcPlay?????，??????、????????????????。 ● AcDown???????C#??，????.NET Framework 2.0??。?????"Acfun?????"。 ??v4.4.3 ?? ??Bilibili????????????? ???????????? ????32??64? Windows XP/Vista/7/8 ???? 32??64? ???Linux ????(1)????????Windows XP???，????????.NET Framework 2.0???(x86)，?????"?????????"??? (2)???????????Linux???，????????Mono?? ??2.10?...Magick.NET: Magick.NET 6.8.6.601: Magick.NET linked with ImageMagick 6.8.6.6. These zip files are also available as a NuGet package: https://nuget.org/profiles/dlemstra/C# Intellisense for Notepad++: Initial release: Members auto-complete Integration with native Notepad++ Auto-Completion Auto "open bracket" for methods Right-arrow to accept suggestions51Degrees.mobi - Mobile Device Detection and Redirection: 2.1.19.4: One Click Install from NuGet This release introduces the 51Degrees.mobi IIS Vary Header Fix. When Compression and Caching is used in IIS, the Vary header is overwritten, making intelligent caching with dynamic content impossible. Find out more about installing the Vary Header fix. Changes to Version 2.1.19.4Handlers now have a ‘Count’ property. This is an integer value that shows how many devices in the dataset that use that handler. Provider.cs -> GetDeviceInfoByID to address a problem w...SMSGateWay: SMSGateWayLaunch: CMPP,SGIP,SMGP ????SP?? ??,????,????,????,VPS??,?????,???. ??????,????,?????,????......????? ????SPID ,MsgSrc,???,???IP,?????? ?????,?????,??,???? ??QQ:3483305Centrify DirectControl PowerShell Module: 1.5.709: -fix- Computer password is correctly set when preparing Computer account for Self-Service join and hostname is longer than 14 charsDLog: DLog v1.0: Log v1.0SalarDbCodeGenerator: SalarDbCodeGenerator v2.1.2013.0719: Version 2.1.2013.0719 2013/7/19 Pattern Changes: * DapperContext pattern is added. * All patterns are updated to work with one-to-one relations. Changes: * One-to-one relation is supported. * Minor bug fixes.PantheR's GraphX for .NET: GraphX for .NET v0.9.5 BETA: BETA 0.9.5 + Added GraphArea.SaveAsImage() method that supports different image formats + Added GraphArea.UseNativeObjectArrange property. True by default. If set to False it will use different coordinates handling that helps to soften vertex drag issues to the top and left area sides. + Added GraphArea.Translation property. It is needed to get correct translation coordinates when determining object position from the mouse coordinates. + Added new VertexControl.PositionChanged event along wit....NET Code Migrator for Dynamics CRM: v1.0.12: Combined the main macros, generated macros from a sample organization, and the CreateVisualStudioMacros utility into a single package.Player Framework by Microsoft: Player Framework for Windows and WP (v1.3 beta 2): Includes all changes in v1.3 beta 1 Additional support for Windows 8.1 Preview New API (JS): addTextTrack New API (JS): msKeys New API (JS): msPlayToPreferredSourceUri New API (JS): msSetMediaKeys New API (JS): onmsneedkey New API (Xaml): SetMediaStreamSource method New API (Xaml): Stretch property New API (Xaml): StretchChanged event New API (Xaml): AreTransportControlsEnabled property New API (Xaml): IsFullWindow property New API (Xaml): PlayToPreferredSourceUri proper...CodeGen Code Generator: CodeGen 4.2.11: Changes in this release include: Added several new alternate forms of the <FIELD_SELWND> token to provide template developers better control over the case of field selection window names. Also added a new token <FIELD_SELWND_ORIGINAL> to preserve the case of selection window names in the same way that <FIELD_SELWND> used to. Enhanced UI Toolkit window script selection window processing (-ws) so that selection window names are no longer case sensitive (they aren't in UI Toolkit). Also the -w...Outlook 2013 Add-In: Multiple Calendars: As per popular request, this new version includes: - Support for multiple calendars. This can be enabled in the configuration by choosing which ones to show/hide appointments from. In some cases (public folders) it may time out and crash, and so far it only supports "My Calendars", so not shared ones yet. Also they're currently shown in the same font/color so there are no confusions with color categories, but please drop me a line on any suggestions you'd like to see implemented. - Added fri...New ProjectsActive Directory Web App Availability Monitor for SCOM 2012: Extend the web application availability monitoring in System Center Operations Manager 2012 with the ability to monitor Active Directory Authenticated Web SitesArgoWinform: ArgoWinform ASP.NET Routing Optional Parameters in body of Urls: This library allows ASP.NET MVC developers to have custom parameters in the body of Urls. Routes that are defined by this library accepts a LookupService that wAutomate Variations in SharePoint 2013 using C#: Automating variations settings and configuration so whenever a deployment is needed, you will be ready with your PowerShell scripts.Automate Variations in SharePoint 2013 using PowerShell: Automating variations settings and configuration so whenever a deployment is needed, you will be ready with your PowerShell scripts.BingosoftSwimming: ?????????ContentCreator for Orchard: Orchard Module that is suposed to replace the Orchard.ContentPicker module by letting you create contentItems directlyGET - General Emitter Templates: GET: General Emitter Templates. Language: C# Given a data file (in xml format), it models the data according with the directives specified in the template file.GTS Project: This project is a private personal educational project to study and learn DNN and ASP.NET MVCJustCompare: Just Compare is human made tool to help humans to compare two digital files. We are now concentrating on source code files only. Media Tool: A collection of tool to manage media files (Pictures and videos)MVVMlight Navigation Service for Windows Phone 8: A simple project to make navigation in MVVMlight on windows phone faster.Qibla Compass for Windows Phone: Qibla compass is one of the mostly used community applications/utility among Muslims. It allows users to determine the correct location / direction of Ka’aba.QuickWebLauncherWP: Una aplicación para windows phone para leer fuentes de sindicación y coleccionar enlaces a los artículos que se desean leerSimpleBingWallpaper: It's a simple project for get bingwallpaper. if you like it. please +1.. ThanksStyrApp: Template Application for technology testingTataFm: Tata FM for Windows 8 app.TimeZoneInfoForm: Exercises timezone related classes and methods in .NET. It can be used as sample code or to troubleshoot suspected timezone issues in .NET.Wix Test: *WIX Test Solution* - is a simple WIX solution for learning some new features. This project is currently in setup mode and free.

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• Using R to Analyze G1GC Log Files

  - by user12620111

  Using R to Analyze G1GC Log Files body, td { font-family: sans-serif; background-color: white; font-size: 12px; margin: 8px; } tt, code, pre { font-family: 'DejaVu Sans Mono', 'Droid Sans Mono', 'Lucida Console', Consolas, Monaco, monospace; } h1 { font-size:2.2em; } h2 { font-size:1.8em; } h3 { font-size:1.4em; } h4 { font-size:1.0em; } h5 { font-size:0.9em; } h6 { font-size:0.8em; } a:visited { color: rgb(50%, 0%, 50%); } pre { margin-top: 0; max-width: 95%; border: 1px solid #ccc; white-space: pre-wrap; } pre code { display: block; padding: 0.5em; } code.r, code.cpp { background-color: #F8F8F8; } table, td, th { border: none; } blockquote { color:#666666; margin:0; padding-left: 1em; border-left: 0.5em #EEE solid; } hr { height: 0px; border-bottom: none; border-top-width: thin; border-top-style: dotted; border-top-color: #999999; } @media print { * { background: transparent !important; color: black !important; filter:none !important; -ms-filter: none !important; } body { 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  Using R to Analyze G1GC Log Files   Using R to Analyze G1GC Log Files Introduction Working in Oracle Platform Integration gives an engineer opportunities to work on a wide array of technologies. My team’s goal is to make Oracle applications run best on the Solaris/SPARC platform. When looking for bottlenecks in a modern applications, one needs to be aware of not only how the CPUs and operating system are executing, but also network, storage, and in some cases, the Java Virtual Machine. I was recently presented with about 1.5 GB of Java Garbage First Garbage Collector log file data. If you’re not familiar with the subject, you might want to review Garbage First Garbage Collector Tuning by Monica Beckwith. The customer had been running Java HotSpot 1.6.0_31 to host a web application server. I was told that the Solaris/SPARC server was running a Java process launched using a commmand line that included the following flags: -d64 -Xms9g -Xmx9g -XX:+UseG1GC -XX:MaxGCPauseMillis=200 -XX:InitiatingHeapOccupancyPercent=80 -XX:PermSize=256m -XX:MaxPermSize=256m -XX:+PrintGC -XX:+PrintGCTimeStamps -XX:+PrintHeapAtGC -XX:+PrintGCDateStamps -XX:+PrintFlagsFinal -XX:+DisableExplicitGC -XX:+UnlockExperimentalVMOptions -XX:ParallelGCThreads=8 Several sources on the internet indicate that if I were to print out the 1.5 GB of log files, it would require enough paper to fill the bed of a pick up truck. Of course, it would be fruitless to try to scan the log files by hand. Tools will be required to summarize the contents of the log files. Others have encountered large Java garbage collection log files. There are existing tools to analyze the log files: IBM’s GC toolkit The chewiebug GCViewer gchisto HPjmeter Instead of using one of the other tools listed, I decide to parse the log files with standard Unix tools, and analyze the data with R. Data Cleansing The log files arrived in two different formats. I guess that the difference is that one set of log files was generated using a more verbose option, maybe -XX:+PrintHeapAtGC, and the other set of log files was generated without that option. Format 1 In some of the log files, the log files with the less verbose format, a single trace, i.e. the report of a singe garbage collection event, looks like this: {Heap before GC invocations=12280 (full 61): garbage-first heap total 9437184K, used 7499918K [0xfffffffd00000000, 0xffffffff40000000, 0xffffffff40000000) region size 4096K, 1 young (4096K), 0 survivors (0K) compacting perm gen total 262144K, used 144077K [0xffffffff40000000, 0xffffffff50000000, 0xffffffff50000000) the space 262144K, 54% used [0xffffffff40000000, 0xffffffff48cb3758, 0xffffffff48cb3800, 0xffffffff50000000) No shared spaces configured. 2014-05-14T07:24:00.988-0700: 60586.353: [GC pause (young) 7324M->7320M(9216M), 0.1567265 secs] Heap after GC invocations=12281 (full 61): garbage-first heap total 9437184K, used 7496533K [0xfffffffd00000000, 0xffffffff40000000, 0xffffffff40000000) region size 4096K, 0 young (0K), 0 survivors (0K) compacting perm gen total 262144K, used 144077K [0xffffffff40000000, 0xffffffff50000000, 0xffffffff50000000) the space 262144K, 54% used [0xffffffff40000000, 0xffffffff48cb3758, 0xffffffff48cb3800, 0xffffffff50000000) No shared spaces configured. } A simple grep can be used to extract a summary: $ grep "\[ GC pause (young" g1gc.log 2014-05-13T13:24:35.091-0700: 3.109: [GC pause (young) 20M->5029K(9216M), 0.0146328 secs] 2014-05-13T13:24:35.440-0700: 3.459: [GC pause (young) 9125K->6077K(9216M), 0.0086723 secs] 2014-05-13T13:24:37.581-0700: 5.599: [GC pause (young) 25M->8470K(9216M), 0.0203820 secs] 2014-05-13T13:24:42.686-0700: 10.704: [GC pause (young) 44M->15M(9216M), 0.0288848 secs] 2014-05-13T13:24:48.941-0700: 16.958: [GC pause (young) 51M->20M(9216M), 0.0491244 secs] 2014-05-13T13:24:56.049-0700: 24.066: [GC pause (young) 92M->26M(9216M), 0.0525368 secs] 2014-05-13T13:25:34.368-0700: 62.383: [GC pause (young) 602M->68M(9216M), 0.1721173 secs] But that format wasn't easily read into R, so I needed to be a bit more tricky. I used the following Unix command to create a summary file that was easy for R to read. $ echo "SecondsSinceLaunch BeforeSize AfterSize TotalSize RealTime" $ grep "\[GC pause (young" g1gc.log | grep -v mark | sed -e 's/[A-SU-z\(\),]/ /g' -e 's/->/ /' -e 's/: / /g' | more SecondsSinceLaunch BeforeSize AfterSize TotalSize RealTime 2014-05-13T13:24:35.091-0700 3.109 20 5029 9216 0.0146328 2014-05-13T13:24:35.440-0700 3.459 9125 6077 9216 0.0086723 2014-05-13T13:24:37.581-0700 5.599 25 8470 9216 0.0203820 2014-05-13T13:24:42.686-0700 10.704 44 15 9216 0.0288848 2014-05-13T13:24:48.941-0700 16.958 51 20 9216 0.0491244 2014-05-13T13:24:56.049-0700 24.066 92 26 9216 0.0525368 2014-05-13T13:25:34.368-0700 62.383 602 68 9216 0.1721173 Format 2 In some of the log files, the log files with the more verbose format, a single trace, i.e. the report of a singe garbage collection event, was more complicated than Format 1. Here is a text file with an example of a single G1GC trace in the second format. As you can see, it is quite complicated. It is nice that there is so much information available, but the level of detail can be overwhelming. I wrote this awk script (download) to summarize each trace on a single line. #!/usr/bin/env awk -f BEGIN { printf("SecondsSinceLaunch IncrementalCount FullCount UserTime SysTime RealTime BeforeSize AfterSize TotalSize\n") } ###################### # Save count data from lines that are at the start of each G1GC trace. # Each trace starts out like this: # {Heap before GC invocations=14 (full 0): # garbage-first heap total 9437184K, used 325496K [0xfffffffd00000000, 0xffffffff40000000, 0xffffffff40000000) ###################### /{Heap.*full/{ gsub ( "\\)" , "" ); nf=split($0,a,"="); split(a[2],b," "); getline; if ( match($0, "first") ) { G1GC=1; IncrementalCount=b[1]; FullCount=substr( b[3], 1, length(b[3])-1 ); } else { G1GC=0; } } ###################### # Pull out time stamps that are in lines with this format: # 2014-05-12T14:02:06.025-0700: 94.312: [GC pause (young), 0.08870154 secs] ###################### /GC pause/ { DateTime=$1; SecondsSinceLaunch=substr($2, 1, length($2)-1); } ###################### # Heap sizes are in lines that look like this: # [ 4842M->4838M(9216M)] ###################### /\[ .*]$/ { gsub ( "\\[" , "" ); gsub ( "\ \]" , "" ); gsub ( "->" , " " ); gsub ( "\\( " , " " ); gsub ( "\ \)" , " " ); split($0,a," "); if ( split(a[1],b,"M") > 1 ) {BeforeSize=b[1]*1024;} if ( split(a[1],b,"K") > 1 ) {BeforeSize=b[1];} if ( split(a[2],b,"M") > 1 ) {AfterSize=b[1]*1024;} if ( split(a[2],b,"K") > 1 ) {AfterSize=b[1];} if ( split(a[3],b,"M") > 1 ) {TotalSize=b[1]*1024;} if ( split(a[3],b,"K") > 1 ) {TotalSize=b[1];} } ###################### # Emit an output line when you find input that looks like this: # [Times: user=1.41 sys=0.08, real=0.24 secs] ###################### /\[Times/ { if (G1GC==1) { gsub ( "," , "" ); split($2,a,"="); UserTime=a[2]; split($3,a,"="); SysTime=a[2]; split($4,a,"="); RealTime=a[2]; print DateTime,SecondsSinceLaunch,IncrementalCount,FullCount,UserTime,SysTime,RealTime,BeforeSize,AfterSize,TotalSize; G1GC=0; } } The resulting summary is about 25X smaller that the original file, but still difficult for a human to digest. SecondsSinceLaunch IncrementalCount FullCount UserTime SysTime RealTime BeforeSize AfterSize TotalSize ... 2014-05-12T18:36:34.669-0700: 3985.744 561 0 0.57 0.06 0.16 1724416 1720320 9437184 2014-05-12T18:36:34.839-0700: 3985.914 562 0 0.51 0.06 0.19 1724416 1720320 9437184 2014-05-12T18:36:35.069-0700: 3986.144 563 0 0.60 0.04 0.27 1724416 1721344 9437184 2014-05-12T18:36:35.354-0700: 3986.429 564 0 0.33 0.04 0.09 1725440 1722368 9437184 2014-05-12T18:36:35.545-0700: 3986.620 565 0 0.58 0.04 0.17 1726464 1722368 9437184 2014-05-12T18:36:35.726-0700: 3986.801 566 0 0.43 0.05 0.12 1726464 1722368 9437184 2014-05-12T18:36:35.856-0700: 3986.930 567 0 0.30 0.04 0.07 1726464 1723392 9437184 2014-05-12T18:36:35.947-0700: 3987.023 568 0 0.61 0.04 0.26 1727488 1723392 9437184 2014-05-12T18:36:36.228-0700: 3987.302 569 0 0.46 0.04 0.16 1731584 1724416 9437184 Reading the Data into R Once the GC log data had been cleansed, either by processing the first format with the shell script, or by processing the second format with the awk script, it was easy to read the data into R. g1gc.df = read.csv("summary.txt", row.names = NULL, stringsAsFactors=FALSE,sep="") str(g1gc.df) ## 'data.frame': 8307 obs. of 10 variables: ## $ row.names : chr "2014-05-12T14:00:32.868-0700:" "2014-05-12T14:00:33.179-0700:" "2014-05-12T14:00:33.677-0700:" "2014-05-12T14:00:35.538-0700:" ... ## $ SecondsSinceLaunch: num 1.16 1.47 1.97 3.83 6.1 ... ## $ IncrementalCount : int 0 1 2 3 4 5 6 7 8 9 ... ## $ FullCount : int 0 0 0 0 0 0 0 0 0 0 ... ## $ UserTime : num 0.11 0.05 0.04 0.21 0.08 0.26 0.31 0.33 0.34 0.56 ... ## $ SysTime : num 0.04 0.01 0.01 0.05 0.01 0.06 0.07 0.06 0.07 0.09 ... ## $ RealTime : num 0.02 0.02 0.01 0.04 0.02 0.04 0.05 0.04 0.04 0.06 ... ## $ BeforeSize : int 8192 5496 5768 22528 24576 43008 34816 53248 55296 93184 ... ## $ AfterSize : int 1400 1672 2557 4907 7072 14336 16384 18432 19456 21504 ... ## $ TotalSize : int 9437184 9437184 9437184 9437184 9437184 9437184 9437184 9437184 9437184 9437184 ... head(g1gc.df) ## row.names SecondsSinceLaunch IncrementalCount ## 1 2014-05-12T14:00:32.868-0700: 1.161 0 ## 2 2014-05-12T14:00:33.179-0700: 1.472 1 ## 3 2014-05-12T14:00:33.677-0700: 1.969 2 ## 4 2014-05-12T14:00:35.538-0700: 3.830 3 ## 5 2014-05-12T14:00:37.811-0700: 6.103 4 ## 6 2014-05-12T14:00:41.428-0700: 9.720 5 ## FullCount UserTime SysTime RealTime BeforeSize AfterSize TotalSize ## 1 0 0.11 0.04 0.02 8192 1400 9437184 ## 2 0 0.05 0.01 0.02 5496 1672 9437184 ## 3 0 0.04 0.01 0.01 5768 2557 9437184 ## 4 0 0.21 0.05 0.04 22528 4907 9437184 ## 5 0 0.08 0.01 0.02 24576 7072 9437184 ## 6 0 0.26 0.06 0.04 43008 14336 9437184 Basic Statistics Once the data has been read into R, simple statistics are very easy to generate. All of the numbers from high school statistics are available via simple commands. For example, generate a summary of every column: summary(g1gc.df) ## row.names SecondsSinceLaunch IncrementalCount FullCount ## Length:8307 Min. : 1 Min. : 0 Min. : 0.0 ## Class :character 1st Qu.: 9977 1st Qu.:2048 1st Qu.: 0.0 ## Mode :character Median :12855 Median :4136 Median : 12.0 ## Mean :12527 Mean :4156 Mean : 31.6 ## 3rd Qu.:15758 3rd Qu.:6262 3rd Qu.: 61.0 ## Max. :55484 Max. :8391 Max. :113.0 ## UserTime SysTime RealTime BeforeSize ## Min. :0.040 Min. :0.0000 Min. : 0.0 Min. : 5476 ## 1st Qu.:0.470 1st Qu.:0.0300 1st Qu.: 0.1 1st Qu.:5137920 ## Median :0.620 Median :0.0300 Median : 0.1 Median :6574080 ## Mean :0.751 Mean :0.0355 Mean : 0.3 Mean :5841855 ## 3rd Qu.:0.920 3rd Qu.:0.0400 3rd Qu.: 0.2 3rd Qu.:7084032 ## Max. :3.370 Max. :1.5600 Max. :488.1 Max. :8696832 ## AfterSize TotalSize ## Min. : 1380 Min. :9437184 ## 1st Qu.:5002752 1st Qu.:9437184 ## Median :6559744 Median :9437184 ## Mean :5785454 Mean :9437184 ## 3rd Qu.:7054336 3rd Qu.:9437184 ## Max. :8482816 Max. :9437184 Q: What is the total amount of User CPU time spent in garbage collection? sum(g1gc.df$UserTime) ## [1] 6236 As you can see, less than two hours of CPU time was spent in garbage collection. Is that too much? To find the percentage of time spent in garbage collection, divide the number above by total_elapsed_time*CPU_count. In this case, there are a lot of CPU’s and it turns out the the overall amount of CPU time spent in garbage collection isn’t a problem when viewed in isolation. When calculating rates, i.e. events per unit time, you need to ask yourself if the rate is homogenous across the time period in the log file. Does the log file include spikes of high activity that should be separately analyzed? Averaging in data from nights and weekends with data from business hours may alias problems. If you have a reason to suspect that the garbage collection rates include peaks and valleys that need independent analysis, see the “Time Series” section, below. Q: How much garbage is collected on each pass? The amount of heap space that is recovered per GC pass is surprisingly low: At least one collection didn’t recover any data. (“Min.=0”) 25% of the passes recovered 3MB or less. (“1st Qu.=3072”) Half of the GC passes recovered 4MB or less. (“Median=4096”) The average amount recovered was 56MB. (“Mean=56390”) 75% of the passes recovered 36MB or less. (“3rd Qu.=36860”) At least one pass recovered 2GB. (“Max.=2121000”) g1gc.df$Delta = g1gc.df$BeforeSize - g1gc.df$AfterSize summary(g1gc.df$Delta) ## Min. 1st Qu. Median Mean 3rd Qu. Max. ## 0 3070 4100 56400 36900 2120000 Q: What is the maximum User CPU time for a single collection? The worst garbage collection (“Max.”) is many standard deviations away from the mean. The data appears to be right skewed. summary(g1gc.df$UserTime) ## Min. 1st Qu. Median Mean 3rd Qu. Max. ## 0.040 0.470 0.620 0.751 0.920 3.370 sd(g1gc.df$UserTime) ## [1] 0.3966 Basic Graphics Once the data is in R, it is trivial to plot the data with formats including dot plots, line charts, bar charts (simple, stacked, grouped), pie charts, boxplots, scatter plots histograms, and kernel density plots. Histogram of User CPU Time per Collection I don't think that this graph requires any explanation. hist(g1gc.df$UserTime, main="User CPU Time per Collection", xlab="Seconds", ylab="Frequency") Box plot to identify outliers When the initial data is viewed with a box plot, you can see the one crazy outlier in the real time per GC. Save this data point for future analysis and drop the outlier so that it’s not throwing off our statistics. Now the box plot shows many outliers, which will be examined later, using times series analysis. Notice that the scale of the x-axis changes drastically once the crazy outlier is removed. par(mfrow=c(2,1)) boxplot(g1gc.df$UserTime,g1gc.df$SysTime,g1gc.df$RealTime, main="Box Plot of Time per GC\n(dominated by a crazy outlier)", names=c("usr","sys","elapsed"), xlab="Seconds per GC", ylab="Time (Seconds)", horizontal = TRUE, outcol="red") crazy.outlier.df=g1gc.df[g1gc.df$RealTime > 400,] g1gc.df=g1gc.df[g1gc.df$RealTime < 400,] boxplot(g1gc.df$UserTime,g1gc.df$SysTime,g1gc.df$RealTime, main="Box Plot of Time per GC\n(crazy outlier excluded)", names=c("usr","sys","elapsed"), xlab="Seconds per GC", ylab="Time (Seconds)", horizontal = TRUE, outcol="red") box(which = "outer", lty = "solid") Here is the crazy outlier for future analysis: crazy.outlier.df ## row.names SecondsSinceLaunch IncrementalCount ## 8233 2014-05-12T23:15:43.903-0700: 20741 8316 ## FullCount UserTime SysTime RealTime BeforeSize AfterSize TotalSize ## 8233 112 0.55 0.42 488.1 8381440 8235008 9437184 ## Delta ## 8233 146432 R Time Series Data To analyze the garbage collection as a time series, I’ll use Z’s Ordered Observations (zoo). “zoo is the creator for an S3 class of indexed totally ordered observations which includes irregular time series.” require(zoo) ## Loading required package: zoo ## ## Attaching package: 'zoo' ## ## The following objects are masked from 'package:base': ## ## as.Date, as.Date.numeric head(g1gc.df[,1]) ## [1] "2014-05-12T14:00:32.868-0700:" "2014-05-12T14:00:33.179-0700:" ## [3] "2014-05-12T14:00:33.677-0700:" "2014-05-12T14:00:35.538-0700:" ## [5] "2014-05-12T14:00:37.811-0700:" "2014-05-12T14:00:41.428-0700:" options("digits.secs"=3) times=as.POSIXct( g1gc.df[,1], format="%Y-%m-%dT%H:%M:%OS%z:") g1gc.z = zoo(g1gc.df[,-c(1)], order.by=times) head(g1gc.z) ## SecondsSinceLaunch IncrementalCount FullCount ## 2014-05-12 17:00:32.868 1.161 0 0 ## 2014-05-12 17:00:33.178 1.472 1 0 ## 2014-05-12 17:00:33.677 1.969 2 0 ## 2014-05-12 17:00:35.538 3.830 3 0 ## 2014-05-12 17:00:37.811 6.103 4 0 ## 2014-05-12 17:00:41.427 9.720 5 0 ## UserTime SysTime RealTime BeforeSize AfterSize ## 2014-05-12 17:00:32.868 0.11 0.04 0.02 8192 1400 ## 2014-05-12 17:00:33.178 0.05 0.01 0.02 5496 1672 ## 2014-05-12 17:00:33.677 0.04 0.01 0.01 5768 2557 ## 2014-05-12 17:00:35.538 0.21 0.05 0.04 22528 4907 ## 2014-05-12 17:00:37.811 0.08 0.01 0.02 24576 7072 ## 2014-05-12 17:00:41.427 0.26 0.06 0.04 43008 14336 ## TotalSize Delta ## 2014-05-12 17:00:32.868 9437184 6792 ## 2014-05-12 17:00:33.178 9437184 3824 ## 2014-05-12 17:00:33.677 9437184 3211 ## 2014-05-12 17:00:35.538 9437184 17621 ## 2014-05-12 17:00:37.811 9437184 17504 ## 2014-05-12 17:00:41.427 9437184 28672 Example of Two Benchmark Runs in One Log File The data in the following graph is from a different log file, not the one of primary interest to this article. I’m including this image because it is an example of idle periods followed by busy periods. It would be uninteresting to average the rate of garbage collection over the entire log file period. More interesting would be the rate of garbage collect in the two busy periods. Are they the same or different? Your production data may be similar, for example, bursts when employees return from lunch and idle times on weekend evenings, etc. Once the data is in an R Time Series, you can analyze isolated time windows. Clipping the Time Series data Flashing back to our test case… Viewing the data as a time series is interesting. You can see that the work intensive time period is between 9:00 PM and 3:00 AM. Lets clip the data to the interesting period:     par(mfrow=c(2,1)) plot(g1gc.z$UserTime, type="h", main="User Time per GC\nTime: Complete Log File", xlab="Time of Day", ylab="CPU Seconds per GC", col="#1b9e77") clipped.g1gc.z=window(g1gc.z, start=as.POSIXct("2014-05-12 21:00:00"), end=as.POSIXct("2014-05-13 03:00:00")) plot(clipped.g1gc.z$UserTime, type="h", main="User Time per GC\nTime: Limited to Benchmark Execution", xlab="Time of Day", ylab="CPU Seconds per GC", col="#1b9e77") box(which = "outer", lty = "solid") Cumulative Incremental and Full GC count Here is the cumulative incremental and full GC count. When the line is very steep, it indicates that the GCs are repeating very quickly. Notice that the scale on the Y axis is different for full vs. incremental. plot(clipped.g1gc.z[,c(2:3)], main="Cumulative Incremental and Full GC count", xlab="Time of Day", col="#1b9e77") GC Analysis of Benchmark Execution using Time Series data In the following series of 3 graphs: The “After Size” show the amount of heap space in use after each garbage collection. Many Java objects are still referenced, i.e. alive, during each garbage collection. This may indicate that the application has a memory leak, or may indicate that the application has a very large memory footprint. Typically, an application's memory footprint plateau's in the early stage of execution. One would expect this graph to have a flat top. The steep decline in the heap space may indicate that the application crashed after 2:00. The second graph shows that the outliers in real execution time, discussed above, occur near 2:00. when the Java heap seems to be quite full. The third graph shows that Full GCs are infrequent during the first few hours of execution. The rate of Full GC's, (the slope of the cummulative Full GC line), changes near midnight.   plot(clipped.g1gc.z[,c("AfterSize","RealTime","FullCount")], xlab="Time of Day", col=c("#1b9e77","red","#1b9e77")) GC Analysis of heap recovered Each GC trace includes the amount of heap space in use before and after the individual GC event. During garbage coolection, unreferenced objects are identified, the space holding the unreferenced objects is freed, and thus, the difference in before and after usage indicates how much space has been freed. The following box plot and bar chart both demonstrate the same point - the amount of heap space freed per garbage colloection is surprisingly low. par(mfrow=c(2,1)) boxplot(as.vector(clipped.g1gc.z$Delta), main="Amount of Heap Recovered per GC Pass", xlab="Size in KB", horizontal = TRUE, col="red") hist(as.vector(clipped.g1gc.z$Delta), main="Amount of Heap Recovered per GC Pass", xlab="Size in KB", breaks=100, col="red") box(which = "outer", lty = "solid") This graph is the most interesting. The dark blue area shows how much heap is occupied by referenced Java objects. This represents memory that holds live data. The red fringe at the top shows how much data was recovered after each garbage collection. barplot(clipped.g1gc.z[,c("AfterSize","Delta")], col=c("#7570b3","#e7298a"), xlab="Time of Day", border=NA) legend("topleft", c("Live Objects","Heap Recovered on GC"), fill=c("#7570b3","#e7298a")) box(which = "outer", lty = "solid") When I discuss the data in the log files with the customer, I will ask for an explaination for the large amount of referenced data resident in the Java heap. There are two are posibilities: There is a memory leak and the amount of space required to hold referenced objects will continue to grow, limited only by the maximum heap size. After the maximum heap size is reached, the JVM will throw an “Out of Memory” exception every time that the application tries to allocate a new object. If this is the case, the aplication needs to be debugged to identify why old objects are referenced when they are no longer needed. The application has a legitimate requirement to keep a large amount of data in memory. The customer may want to further increase the maximum heap size. Another possible solution would be to partition the application across multiple cluster nodes, where each node has responsibility for managing a unique subset of the data. Conclusion In conclusion, R is a very powerful tool for the analysis of Java garbage collection log files. The primary difficulty is data cleansing so that information can be read into an R data frame. Once the data has been read into R, a rich set of tools may be used for thorough evaluation.

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• How to handle this unfortunately non hypothetical situation with end-users?

  - by User Smith

  I work in a medium sized company but with a very small IT force. Last year (2011), I wrote an application that is very popular with a large group of end-users. We hit a deadline at the end of last year and some functionality (I will call funcA from now on) was not added into the application that was wanted at the very end. So, this application has been running in live/production since the end of 2011, I might add without issue. Yesterday, a whole group of end-users started complaining that funcA that was never in the application is no longer working. Our priority at this company is that if an application is broken it must be fixed first prior to prioritized projects. I have compared code and queries and there is no difference since 2011, which is proofA. I then was able to get one of the end-users to admit that it never worked proofB, but since then that end-user has went back and said that it was working previously......I believe the horde of end-users has assimilated her. I have also reviewed my notes for this project which has requirements and daily updates regarding the project which specifically states, "funcA not achieved due to time constraints", proofC. I have spoken with many of them and I can see where they could be confused as they are very far from a programming background, but I also know they are intelligent enough to act in a group in order to bypass project prioritization orders in order to get functionality that they want to make their job easier. The worst part is is that now group think is setting in and my boss and the head of IT is actually starting to believe them, even though there is no code or query changes. As far as reviewing the state of the logic it is very cut and dry to the point of if 1 = 1, funcA will not work. So, this is the end of the description of my scenario, but I am trying not to get severally dinged on my performance metrics due to this which would essentially have me moved to fixing a production problem that doesn't exist that will probably take over 1 month. I am looking for direct answers to this question. This question is not for rants, polling, or discussions as this is not the format for StackExchange. Please don't downvote me too terribly it is pretty common on this specific site of stack, I am looking for honest answers to this situation and I couldn't find a forum more appropriate.

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• How to Overcome or fix MIXED_DML_OPERATION error in Salesforce APEX without future method ?

  - by sathya

  How to Overcome or fix MIXED_DML_OPERATION error in Salesforce APEX without future method ?MIXED_DML_OPERATION :-one of the worst issues we have ever faced :)While trying to perform DML operation on a setup object and non-setup object in a single action you will face this error.Following are the solutions I tried and the final one worked out :-1. perform the 1st objects DML on normal apex method. Then Call the 2nd objects DML through a future method.    Drawback :- You cant get a response from the future method as its context is different and because its executing asynchronously and that its static.2. Tried the following option but it didnt work :-    1. perform the dml operation on the normal apex method.    2. tried calling the 2nd dml from trigger thinking that it would be in a different context. But it didnt work.    3. Some suggestions were given in some blogs that we could try System.runas()   Unfortunately that works only for test class.   4. Finally achieved it with response synchronously through the following solution :-    a. Created 2 apex:commandbuttons :-        1. <apex:commandButton value="Save and Send Activation Email" action="{!CreateContact}"  rerender="junkpanel" oncomplete="callSimulateUserSave()">            Note :- Oncomplete will not work if you dont have a rerender attribute. So just try refreshing a junk panel.        2. <apex:commandButton value="SimulateUserSave" id="SimulateUserSave" action="{!SaveUser}"  style="display:none;margin-left:5px;"/>        Have a junk panel as well just for rerendering  :-        <apex:outputPanel id="junkpanel"></apex:outputPanel>    b. Created this javascript function which is called from first button's oncomplete and clicks the second button :-                function callSimulateUserSave()                {                    // Specify the id of the button that needs to be clicked. This id is based on the Apex Component Hierarchy.                    // You will not get this value if you dont have the id attribute in the button which needs to be clicked from javascript                    // If you have any doubt in getting this value. Just hover over the button using Chrome developer tools to get the id.                    // But it will show like theForm:SimulateUserSave but you need to replace the colon with a dot here.                    // Note :- I have given display:none in the style of the second button to make sure that, it is not visible for the user.                    var mybtn=document.getElementById('{!$Component.theForm.SimulateUserSave}');                                    mybtn.click();                }    c. Apex Methods CreateContact and SaveUser are the pagereference methods which contains the code to create contact and user respectively.       After inserting the user inside the second apex method you can just set some public Properties in the page,        for ex:- created userid to get the user details and display in the page to show the acknowledgement to the users that the User is created.

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• Database Migration Scripts: Getting from place A to place B

  - by Phil Factor

  We’ll be looking at a typical database ‘migration’ script which uses an unusual technique to migrate existing ‘de-normalised’ data into a more correct form. So, the book-distribution business that uses the PUBS database has gradually grown organically, and has slipped into ‘de-normalisation’ habits. What’s this? A new column with a list of tags or ‘types’ assigned to books. Because books aren’t really in just one category, someone has ‘cured’ the mismatch between the database and the business requirements. This is fine, but it is now proving difficult for their new website that allows searches by tags. Any request for history book really has to look in the entire list of associated tags rather than the ‘Type’ field that only keeps the primary tag. We have other problems. The TypleList column has duplicates in there which will be affecting the reporting, and there is the danger of mis-spellings getting there. The reporting system can’t be persuaded to do reports based on the tags and the Database developers are complaining about the unCoddly things going on in their database. In your version of PUBS, this extra column doesn’t exist, so we’ve added it and put in 10,000 titles using SQL Data Generator. /* So how do we refactor this database? firstly, we create a table of all the tags. */IF  OBJECT_ID('TagName') IS NULL OR OBJECT_ID('TagTitle') IS NULL  BEGIN  CREATE TABLE  TagName (TagName_ID INT IDENTITY(1,1) PRIMARY KEY ,     Tag VARCHAR(20) NOT NULL UNIQUE)  /* ...and we insert into it all the tags from the list (remembering to take out any leading spaces */  INSERT INTO TagName (Tag)     SELECT DISTINCT LTRIM(x.y.value('.', 'Varchar(80)')) AS [Tag]     FROM     (SELECT  Title_ID,          CONVERT(XML, '<list><i>' + REPLACE(TypeList, ',', '</i><i>') + '</i></list>')          AS XMLkeywords          FROM   dbo.titles)g    CROSS APPLY XMLkeywords.nodes('/list/i/text()') AS x ( y )  /* we can then use this table to provide a table that relates tags to articles */  CREATE TABLE TagTitle   (TagTitle_ID INT IDENTITY(1, 1),   [title_id] [dbo].[tid] NOT NULL REFERENCES titles (Title_ID),   TagName_ID INT NOT NULL REFERENCES TagName (Tagname_ID)   CONSTRAINT [PK_TagTitle]       PRIMARY KEY CLUSTERED ([title_id] ASC, TagName_ID)       ON [PRIMARY])        CREATE NONCLUSTERED INDEX idxTagName_ID  ON  TagTitle (TagName_ID)  INCLUDE (TagTitle_ID,title_id)        /* ...and it is easy to fill this with the tags for each title ... */        INSERT INTO TagTitle (Title_ID, TagName_ID)    SELECT DISTINCT Title_ID, TagName_ID      FROM        (SELECT  Title_ID,          CONVERT(XML, '<list><i>' + REPLACE(TypeList, ',', '</i><i>') + '</i></list>')          AS XMLkeywords          FROM   dbo.titles)g    CROSS APPLY XMLkeywords.nodes('/list/i/text()') AS x ( y )    INNER JOIN TagName ON TagName.Tag=LTRIM(x.y.value('.', 'Varchar(80)'))    END    /* That's all there was to it. Now we can select all titles that have the military tag, just to try things out */SELECT Title FROM titles  INNER JOIN TagTitle ON titles.title_ID=TagTitle.Title_ID  INNER JOIN Tagname ON Tagname.TagName_ID=TagTitle.TagName_ID  WHERE tagname.tag='Military'/* and see the top ten most popular tags for titles */SELECT Tag, COUNT(*) FROM titles  INNER JOIN TagTitle ON titles.title_ID=TagTitle.Title_ID  INNER JOIN Tagname ON Tagname.TagName_ID=TagTitle.TagName_ID  GROUP BY Tag ORDER BY COUNT(*) DESC/* and if you still want your list of tags for each title, then here they are */SELECT title_ID, title, STUFF(  (SELECT ','+tagname.tag FROM titles thisTitle    INNER JOIN TagTitle ON titles.title_ID=TagTitle.Title_ID    INNER JOIN Tagname ON Tagname.TagName_ID=TagTitle.TagName_ID  WHERE ThisTitle.title_id=titles.title_ID  FOR XML PATH(''), TYPE).value('.', 'varchar(max)')  ,1,1,'')    FROM titles  ORDER BY title_ID So we’ve refactored our PUBS database without pain. We’ve even put in a check to prevent it being re-run once the new tables are created. Here is the diagram of the new tag relationship We’ve done both the DDL to create the tables and their associated components, and the DML to put the data in them. I could have also included the script to remove the de-normalised TypeList column, but I’d do a whole lot of tests first before doing that. Yes, I’ve left out the assertion tests too, which should check the edge cases and make sure the result is what you’d expect. One thing I can’t quite figure out is how to deal with an ordered list using this simple XML-based technique. We can ensure that, if we have to produce a list of tags, we can get the primary ‘type’ to be first in the list, but what if the entire order is significant? Thank goodness it isn’t in this case. If it were, we might have to revisit a string-splitter function that returns the ordinal position of each component in the sequence. You’ll see immediately that we can create a synchronisation script for deployment from a comparison tool such as SQL Compare, to change the schema (DDL). On the other hand, no tool could do the DML to stuff the data into the new table, since there is no way that any tool will be able to work out where the data should go. We used some pretty hairy code to deal with a slightly untypical problem. We would have to do this migration by hand, and it has to go into source control as a batch. If most of your database changes are to be deployed by an automated process, then there must be a way of over-riding this part of the data synchronisation process to do this part of the process taking the part of the script that fills the tables, Checking that the tables have not already been filled, and executing it as part of the transaction. Of course, you might prefer the approach I’ve taken with the script of creating the tables in the same batch as the data conversion process, and then using the presence of the tables to prevent the script from being re-run. The problem with scripting a refactoring change to a database is that it has to work both ways. If we install the new system and then have to rollback the changes, several books may have been added, or had their tags changed, in the meantime. Yes, you have to script any rollback! These have to be mercilessly tested, and put in source control just in case of the rollback of a deployment after it has been in place for any length of time. I’ve shown you how to do this with the part of the script .. /* and if you still want your list of tags for each title, then here they are */SELECT title_ID, title, STUFF(  (SELECT ','+tagname.tag FROM titles thisTitle    INNER JOIN TagTitle ON titles.title_ID=TagTitle.Title_ID    INNER JOIN Tagname ON Tagname.TagName_ID=TagTitle.TagName_ID  WHERE ThisTitle.title_id=titles.title_ID  FOR XML PATH(''), TYPE).value('.', 'varchar(max)')  ,1,1,'')    FROM titles  ORDER BY title_ID …which would be turned into an UPDATE … FROM script. UPDATE titles SET  typelist= ThisTaglistFROM     (SELECT title_ID, title, STUFF(    (SELECT ','+tagname.tag FROM titles thisTitle      INNER JOIN TagTitle ON titles.title_ID=TagTitle.Title_ID      INNER JOIN Tagname ON Tagname.TagName_ID=TagTitle.TagName_ID    WHERE ThisTitle.title_id=titles.title_ID    ORDER BY CASE WHEN tagname.tag=titles.[type] THEN 1 ELSE 0  END DESC    FOR XML PATH(''), TYPE).value('.', 'varchar(max)')    ,1,1,'')  AS ThisTagList  FROM titles)fINNER JOIN Titles ON f.title_ID=Titles.title_ID You’ll notice that it isn’t quite a round trip because the tags are in a different order, though we’ve managed to make sure that the primary tag is the first one as originally. So, we’ve improved the database for the poor book distributors using PUBS. It is not a major deal but you’ve got to be prepared to provide a migration script that will go both forwards and backwards. Ideally, database refactoring scripts should be able to go from any version to any other. Schema synchronization scripts can do this pretty easily, but no data synchronisation scripts can deal with serious refactoring jobs without the developers being able to specify how to deal with cases like this.

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• HTML5 game programming style

  - by fnx

  I am currently trying learn javascript in form of HTML5 games. Stuff that I've done so far isn't too fancy since I'm still a beginner. My biggest concern so far has been that I don't really know what is the best way to code since I don't know the pros and cons of different methods, nor I've found any good explanations about them. So far I've been using the worst (and propably easiest) method of all (I think) since I'm just starting out, for example like this: var canvas = document.getElementById("canvas"); var ctx = canvas.getContext("2d"); var width = 640; var height = 480; var player = new Player("pic.png", 100, 100, ...); also some other global vars... function Player(imgSrc, x, y, ...) { this.sprite = new Image(); this.sprite.src = imgSrc; this.x = x; this.y = y; ... } Player.prototype.update = function() { // blah blah... } Player.prototype.draw = function() { // yada yada... } function GameLoop() { player.update(); player.draw(); setTimeout(GameLoop, 1000/60); } However, I've seen a few examples on the internet that look interesting, but I don't know how to properly code in these styles, nor do I know if there are names for them. These might not be the best examples but hopefully you'll get the point: 1: Game = { variables: { width: 640, height: 480, stuff: value }, init: function(args) { // some stuff here }, update: function(args) { // some stuff here }, draw: function(args) { // some stuff here }, }; // from http://codeincomplete.com/posts/2011/5/14/javascript_pong/ 2: function Game() { this.Initialize = function () { } this.LoadContent = function () { this.GameLoop = setInterval(this.RunGameLoop, this.DrawInterval); } this.RunGameLoop = function (game) { this.Update(); this.Draw(); } this.Update = function () { // update } this.Draw = function () { // draw game frame } } // from http://www.felinesoft.com/blog/index.php/2010/09/accelerated-game-programming-with-html5-and-canvas/ 3: var engine = {}; engine.canvas = document.getElementById('canvas'); engine.ctx = engine.canvas.getContext('2d'); engine.map = {}; engine.map.draw = function() { // draw map } engine.player = {}; engine.player.draw = function() { // draw player } // from http://that-guy.net/articles/ So I guess my questions are: Which is most CPU efficient, is there any difference between these styles at runtime? Which one allows for easy expandability? Which one is the most safe, or at least harder to hack? Are there any good websites where stuff like this is explained? or... Does it all come to just personal preferance? :)

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• TechEd 2010 Day Three: The Database Designer (Isn't)

  - by BuckWoody

  Yesterday at TechEd 2010 here in New Orleans I worked the front-booth, answering general SQL Server questions for the masses. I was actually a little surprised to find most of the questions I got were from folks that wanted to know more about Stream Insight and Master Data Services. In past conferences I've been asked a lot of "free consulting" questions, about problems folks have had from older products. I don't mind that a bit - in fact, I'm always happy to help in any way I can. But this time people are really interested in the new features in the product, and I like that they are thinking ahead, not just having to solve problems in production. My presentation was on "Database Design in an Hour". We had the usual fun, and SideShow Bob made an appearance - I kid you not. The guy in the back of the room looked just like Sideshow Bob, so I quickly held a "bes thair" contest, and he won. Duing the presentation, I explain the tools you can use to design databases. I also explain that the "Database Designer" tool in SQL Server Management Studio (SSMS) isn't truly a desinger - it uses non-standard notation, doesn't have a meta-data dictionary, and worst of all, it works at the physical level. In other words, whatever you do in SSMS will automatically change the field/table/relationship structures in the database. We fixed this in SSMS 2008 and higher by adding an option to block that, but the tool is not a good design function nonetheless. To be fair, no one I know of at Microsoft recommends that it is - but I was shocked to hear so many developers in the room defending it as a good tool. I think the main issue for someone who doesn't have to work with Relational Systems a great deal is that it can be difficult to figure out Foreign Keys. The syntax makes them look "backwards", so it's just easier to grab a field and place it on the table you want to point to. There are options. You can download a couple of free tools (CA has a community edition of ER-WIN, Quest has one, and Embarcadero also has one) and if you design more than one or two databases a year, it may be worth buying a true design tool. For years I used Visio, but we changed it so that it doesn't forward-engineer (create the DDL) any more, so it isn't a true design tool either. So investigate those free and not-so-free tools. You'll find they help you in your job - but stay away from the Database Designer in SSMS. Or I'll send Sideshow Bob over there to straighten you out. Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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• a friendly elaboratation on how iceweasel misses as recent request was discovered in post tut

  - by v3x3n

  I would like to specify what you asked about in how iceweasel misses on in hopes that you are interested in considering the answer to be valid considering the package should run efficient to a novice user especially when getting a first impression on a new software, browser, or package they are given by default. First let me say that I am very grateful for all debian has and continues to do for its user base and I am not complaining, only hoping that in mentioning such it will eventually aid in improving the disappointing experience iceweasel gave me in multiple ways right from the start of using it. I am sure tremendous amounts of hard work went into making it work as well as it does, and tremendous effort continues to go into IW like the rest of the package and distros such as this... Having said that, I do aim to keep my examples simple as possible but also explained in enough detail as to not leave out important info to get a full idea of my issue... (Thanks for understanding if I sound novice to debian, I am but continue to learn and advance by trial and error each day, and of course the wonderful help from all the great minds available here and there)... Well, my bone to pick (unfortunately as I disdain being a complainer when so much has been done for us, the end user) with IW is mainly 3 immediately noticed problems in offering me a smooth test drive (completely normal browsing conduct of your average user, I should indicate) as soon as I started out a task using IW (heading directly to google images and searched for a few web sized images, then saved a few (no more than 800 to 900 in dimensions, typically a normal procedure I would imagine) I experienced a horrendous reoccurring freeze and lag time that almost left me to kill the process more than once on each attempt and continued to compound so that by a few attempts later, even 1 single image save locked up the entire browser, ultimately giving up on my procedure in its simplicity with a bit of aggravation, if there was something I had done wrong on my end pre-attempt or during installation. Secondly, visiting video player sites in this case youtube will not allow for any video feed to play whatsoever and again, experienced a slight freezing that eventually dissipated as long as I didn't attempt to press play or reload another video trial... Very annoying and possibly related to my first issue (which could rely on my own lack of knowledge in setup config, but that troubles me if so).... Lastly as another user has stated already, in which brought you to ask them what exactly seemed to be the problem in the first place is also my final straw that broke the weasel's back, leading me here to find a solution to a updated version of firefox... being that iceweasel (an apparent build of firefox 17.x.x) leaving the user to find themselves out of luck when installing their favorite or much useful add-ons or plugins that aid their task or normal usage online.... As the other user clearly stated... there is almost zero options and barely any luck to find compatible plugins with such an outdated version still being used... I can only imagine if as a novoice or standard user to linux... and beginner to debian (which I am all for btw!) if I am discovering major conductivity issues which hinder normal user conduct right off the bat... that there is probably a bundle or more of security vulnerabilities that would unravel to me if I continued to give mr Hommey's package any further attention, or interest in continuing to use... This is a deal breaker on any account, unless all 3 of these issues stated are due to a very n00berish setting or lack thereof (which if that is the case, such was not properly stated for beginner in any place available by following installation tutorials such as LVM installers, which I felt lacked a clear understanding to someone who is trying to learn why and how, rather than, a fix to a potentially broken out of box installation... I really think that is irrelevant in any case however, as there is much step by step support regarding that kind of thing, just saying... its very challenging, along side a job to keep deadlines on, and the need to learn a better and more costomizible system, that was not as popularized when I became a dev via windows (OK OK I know thats a huge mistake and now I am way off original topic but anyway) Thanks very much for taking the time to read over this, and I hope it honestly gives you a few good and valid reasons for users wanting and seeking a way to get around iceweasel altogether... Finally, if I am missing something vital that renders all I've stated invalid or useless, please feel free to shove that elephant in the room my direction! Thanks for all you do, as I am sure it is very useful and dedicated, being you are a debian maintainer, and super user! Much love for intelligence, freedom and sharing the secrets of the web! May it remain unregulated and a good place to grow and learn for generations to come! Stay true! Take care now! -v3x (v3x @ gmx .com)

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• Event-Driven Debugging

  - by Brian Donahue

  Most application troubleshooting involves getting an error, analyzing the error message, and at worst, attaching a debugger to work out the real cause. What is not really covered is how to troubleshoot an applicaiton that is not errant, but is having a performance issue, and more than likely, in the middle of the night when you are snug in your bed, sawing logs. What you need is an ever-vigilant cyborg who never sleeps to sit in front of your server all night, but as SkyNet is not live yet, you can settle for the next-best thing. Windows provides performance counters and alerts that can tell you when an applicaiton reaches an unacceptable threshold of naughty behavior, but although it can tattle on your brainchild, it won't be the child psychiatrist that you need to tell you why he's pulling your server's pigtails and pulling faces at the teacher. What you need is to plug a debugger into performance monitor and have it tell you what's going on with your applicaiton at the time. For this purpose, I'd used Microsoft's MDbgEngine as the basis for an applicaiton that will dump a program's stacks, I call it Application Slicer Dicer Wonder Dumper Super Cyborg, or StackOMatic for short. StackOMatic can look at a program's behavior and tell you if the stacks are not moving, but it can also work on the command-line to dump all managed methods on the stack at will. Now that there is a command you can use to dump the stacks, all you need to do is politely tell Windows to run it when you're displeased with your creation as it's trashing the CPU of your server at 3 AM. The first step is to create a scheduled task to tell StackOMatic to dump your applicaiton. Start Task Scheduler and right-click Task Scheduler Library and then Create Task. For this exercise I'm creating a task that will dump the Red Gate SQL Monitor Base Monitor Service. In the Actions tab, I enter the path to StackOMatic and use the arguments to log the stack dump to a file: /PN:RedGate.Response.Engine.Alerting.Base.Service /OUT:c:\users\administrator\MonitorLog.txt Next, I go into Windows Server 2008's Reliability and Performance Monitor and add a new Data Collector Set. This set will produce an alert on the %Processor Time for the service. When the processor time breaches 50%, it will run the StackDumpBaseService task I created. Whenever the service misbehaves, it will append to the log file. Now when I go to work in the morning, I can see what the service was doing when it overloaded the processor and take action.

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• Help with DB Structure, vOD site

  - by Chud37

  I have a video on demand style site that hosts series of videos under different modules. However with the way I have designed the database it is proving to be very slow. I have asked this question before and someone suggested indexing, but i cannot seem to get my head around it. But I would like someone to help with the structure of the database here to see if it can be improved. The core table is Videos: ID bigint(20) (primary key, auto-increment) pID text airdate text title text subject mediumtext url mediumtext mID int(11) vID int(11) sID int(11) pID is a unique 5 digit string to each video that is a shorthand identifier. Airdate is the TS, (stored in text format, right there maybe I should change that to TIMESTAMP AUTO UPDATE), title is self explanatory, subject is self explanatory, url is the hard link on the site to the video, mID is joined to another table for the module title, vID is joined to another table for the language of the video, (english, russian, etc) and sID is the summary for the module, a paragraph stored in an external database. The slowest part of the website is the logging part of it. I store the data in another table called 'Hits': id mediumint(10) (primary key, auto-increment) progID text ts int(10) Again, here (this was all made a while ago) but my Timestamp (ts) is an INT instead of ON UPDATE CURRENT TIMESTAMP, which I guess it should be. However This table is now 47,492 rows long and the script that I wrote to process it is very very slow, so slow in fact that it times out. A row is added to this table each time a user clicks 'Play' on the website and then so the progID is the same as the pID, and it logs the php time() timestamp in ts. Basically I load the entire database of 'Hits' into an array and count the hits in each day using the TS column. I am guessing (i'm quite slow at all this, but I had no idea this would happen when I built the thing) that this is possibly the worst way to go about this. So my questions are as follows: Is there a better way of structuring the 'Videos' table, is so, what do you suggest? Is there a better way of structuring 'hits', if so, please help/tell me! Or is it the fact that my tables are fine and the PHP coding is crappy?

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• Should we persist with an employee still writing bad code after many years?

  - by user94986

  I've been assigned the task of managing developers for a well-established company. They have a single developer who specialises in all their C++ coding (since forever), but the quality of the work is abysmal. Code reviews and testing have revealed many problems, one of the worst being memory leaks. The developer has never tested his code for leaks, and I discovered that the applications could leak many MBs with only a minute of use. User's were reporting huge slowdowns, and his take was, "it's nothing to do with me - if they quit and restart, it's all good again." I've given him tools to detect and trace the leaks, and sat down with him for many hours to demonstrate how the tools are used, where the problems occur, and what to do to fix them. We're 6 months down the track, and I assigned him to write a new module. I reviewed it before it was integrated into our larger code base, and was dismayed to discover the same bad coding as before. The part that I find incomprehensible is that some of the coding is worse than amateurish. For example, he wanted a class (Foo) that could populate an object of another class (Bar). He decided that Foo would hold a reference to Bar, e.g.: class Foo { public: Foo(Bar& bar) : m_bar(bar) {} private: Bar& m_bar; }; But (for other reasons) he also needed a default constructor for Foo and, rather than question his initial design, he wrote this gem: Foo::Foo() : m_bar(*(new Bar)) {} So every time the default constructor is called, a Bar is leaked. To make matters worse, Foo allocates memory from the heap for 2 other objects, but he didn't write a destructor or copy constructor. So every allocation of Foo actually leaks 3 different objects, and you can imagine what happened when a Foo was copied. And - it only gets better - he repeated the same pattern on three other classes, so it isn't a one-off slip. The whole concept is wrong on so many levels. I would feel more understanding if this came from a total novice. But this guy has been doing this for many years and has had very focussed training and advice over the past few months. I realise he has been working without mentoring or peer reviews most of that time, but I'm beginning to feel he can't change. So my question is, would you persist with someone who is writing such obviously bad code?

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• Reasons NOT to use JSF [closed]

  - by Vain Fellowman

  I am new to StackExchange, but I figured you would be able to help me. We're crating a new Java Enterprise application, replacing an legacy JSP solution. Due to many many changes, the UI and parts of the business logic will completely be rethought and reimplemented. Our first thought was JSF, as it is the standard in Java EE. At first I had a good impression. But now I am trying to implement a functional prototype, and have some really serious concerns about using it. First of all, it creates the worst, most cluttered invalid pseudo-HTML/CSS/JS mix I've ever seen. It violates every single rule I learned in web-development. Furthermore it throws together, what never should be so tightly coupled: Layout, Design, Logic and Communication with the server. I don't see how I would be able to extend this output comfortably, whether styling with CSS, adding UI candy (like configurable hot-keys, drag-and-drop widgets) or whatever. Secondly, it is way too complicated. Its complexity is outstanding. If you ask me, it's a poor abstraction of basic web technologies, crippled and useless in the end. What benefits do I have? None, if you think about. Hundreds of components? I see ten-thousands of HTML/CSS snippets, ten-thousands of JavaScript snippets and thousands of jQuery plug-ins in addition. It solves really many problems - we wouldn't have if we wouldn't use JSF. Or the front-controller pattern at all. And Lastly, I think we will have to start over in, say 2 years. I don't see how I can implement all of our first GUI mock-up (Besides; we have no JSF Expert in our team). Maybe we could hack it together somehow. And then there will be more. I'm sure we could hack our hack. But at some point, we'll be stuck. Due to everything above the service tier is in control of JSF. And we will have to start over. My suggestion would be to implement a REST api, using JAX-RS. Then create a HTML5/Javascript client with client side MVC. (or some flavor of MVC..) By the way; we will need the REST api anyway, as we are developing a partial Android front-end, too. I doubt, that JSF is the best solution nowadays. As the Internet is evolving, I really don't see why we should use this 'rake'. Now, what are pros/cons? How can I emphasize my point to not use JSF? What are strong points to use JSF over my suggestion?

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• ASP.NET Wizard control with Dynamic UserControls

  - by wjat777

  Hello everyone I'm trying to use the Wizard control as follows: 1 - In the first step (first screen) has a cheklistbox with several options 2 - For each option selected, will be created an extra step 3 - In some steps may be set up intermediate stages Me problem is that each step is a usercontrol. So if the first step I select option1 and option3, I should create two more steps with usercontrol1 and UserControl3 .... Someone already did something similar? I will try explain better the problem. I'll paste here, but I put a copy of the project in skydrive: http://cid-3d949f1661d00819.skydrive.live.com/self.aspx/C%5E3/WizardControl2.7z It is a very basic example of what I'm trying to do. The project has page.ASPX 1 and 3 usercontrol.ASCX (UC1, UC2 and UC3) Default.ASPX: <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="WebApplication2._Default" % Option1 Option2 Option3 Code Behind: using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; namespace WebApplication2 { public partial class _Default : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { } protected void Page_PreInit(object sender, EventArgs e) { LoadSteps(); } private void LoadSteps() { int count = Wizard1.WizardSteps.Count; for (int i = count - 1; i > 0; i--) { WizardStepBase step = Wizard1.WizardSteps[i]; if (step.StepType != WizardStepType.Start) Wizard1.WizardSteps.Remove(step); } string Activities=""; foreach (ListItem item in CheckBoxList1.Items) { if (item.Selected) { WizardStep step = new WizardStep {ID = "step_" + item.Value, Title = "step_" + item.Value}; UserControl uc=null; switch (item.Value) { case "1": uc=(UserControl)LoadControl("~/UC1.ascx"); break; case "2": uc=(UserControl)LoadControl("~/UC2.ascx"); break; case "3": uc=(UserControl)LoadControl("~/UC3.ascx"); break; } step.Controls.Add(uc); Wizard1.WizardSteps.Add(step); } } } protected void CheckBoxList1_SelectedIndexChanged(object sender, EventArgs e) { LoadSteps(); } } } Control UC1.ASCX to UC3.ASCX has the same code (as an example) usercontrol.ascx: <%@ Control Language="C#" AutoEventWireup="true" CodeBehind="UC1.ascx.cs" Inherits="WebApplication2.UC1" % AutoPostBack="True" AutoPostBack="True" Code Behind: using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; namespace WebApplication2 { public partial class UC1 : System.Web.UI.UserControl { protected void Page_Init(object sender, EventArgs e) { List list1 = new List { "Alice", "Bob", "Chris" }; List list2 = new List { "UN", "DEUX", "TROIS" }; DropDownList1.DataSource = list1; DropDownList2.DataSource = list2; DropDownList1.DataBind(); DropDownList2.DataBind(); } protected void Page_Load(object sender, EventArgs e) { if (IsPostBack) return; } protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e) { Label1.Text = DropDownList1.SelectedValue; } protected void DropDownList2_SelectedIndexChanged(object sender, EventArgs e) { Label2.Text = DropDownList2.SelectedValue; } } } You can see that the controls UserControls trigger events (they cause postbacks) The behavior of this project is a little different than I described in the first thread, but the problem is the same. After the second time "next" button, you will get an error. Thanks in advance William

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