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• first install for windows eight.....da beta

  - by raysmithequip

  The W8 preview is now installed and I am enjoying it.  I remember the learning curve of my first unix machine back in the eighties, this ain't that.It is normal for me to do the first os install with a keyboard and low end monitor...you never know what you'll encounter out in the field.  The OS took like a fish to water.  I used a low end INTEL motherboard dp55w I gathered on the cheap, an 1157 i5 from the used bin a pair of 6 gig ddr3 sticks, a rosewell 550 watt power supply a cheap used twenty buck sub 200g wd sata drive, a half working dvd burner and an asus fanless nvidia vid card, not a great one but Sub 50.00 on newey eggey...I did have to hunt the ms forums for a key and of course to activate the thing, if dos would of needed this outmoded ritual, we would still be on cpm and osborne would be a household name, of course little do people know that this ritual was common as far back as the seventies on att unix installs....not, but it was possible, I used to joke about when I ran a bbs, what hell would of been wrought had dos 3.2 machines been required to dial into my bbs to send fido mail to ms and wait for an acknowledgement.  All in all the thing was pushing a seven on the ms richter scale, not including the vid card, sadly it came in at just a tad over three....I wanted to evaluate it for a possible replacement on critical machines that in the past went down due to a vid card fan failure....you have no idea what a customer thinks when you show them a failed vid card fan..."you mean that little plastic piece of junk caused all this!!??!!!"...yea man.  Some production machines don't need any sort of vid, I will at least keep it on the maybe list for those, MTBF is a very important factor, some big box stores should put percentage of failure rate within 24 month estimates on the outside of the carton for sure.  And a warning that the power supplies are already at their limit.  Let's face it, today even 550w can be iffy.A few neat eye candy improvements over the earlier windows is nice, the metro screen is nice, anyone who has used a newer phone recently will intuitively drag their fingers across the screen....lot of good that was with no mouse or touch screen though.  Lucky me, I have been using windows since day one, I still have a copy of win 2.0 (and every other version) for no good reason.  Still the old ix collection of disks is much larger, recompiling any kernal is another silly ritual, same machine, different day, same recompile...argh. Rh is my all time fav, mandrake was always missing something, like it rewrote the init file or something, novell is ok as long as you stay on the beaten path and of course ubuntu normally recompiles with the same errors consistantly....makes life easy that way....no errors on windows eight, just a screen that did not match the installed hardware, natuarally I alt tabbed right out of it, then hit the flag key to find the start menu....no start button. I miss the start button already. Keyboard cowboy funnin and I was browsing the harddrive, nothing stunning there, I like that, means I can find stuff. Only I can't find what I want, the start button....the start menu is that first screen for touch tablets. No biggie for useruser, that is where they will want to be, I can see that. Admins won't want to be there, it is easy enough to get the control panel a bazzilion other ways though, just not the start button. (see a pattern here?). Personally, from the keyboard I find it fun to hit the carets along the location bar at the top of the explorer screen with tabs and arrows and choose SHOW ALL CONTROL PANEL ITEMS, or thereabouts. Bottom line, I love seven and I'll love eight even more!...very happy I did not have to follow the normal rule of thumb (a customer watching me build a system and asking questions said "oh I get it, so every piece you put in there is basically a hundred bucks, right?)...ok, sure, pretty much, more or less, well, ya dude.  It will be WAY past october till I get a real touch screen but I did pick up a pair of cheap tatungs so I can try the NEW main start screen, I parse a lot of folders and have a vision of how a pair of touch screens will be easier than landing a rover on mars.  Ok.  fine, they are way smallish, and I don't expect multitouch to work but we are talking a few percent of a new 21 inch viewsonic touch screen.  Will this OS be a game changer?  I don't know.  Bottom line with all the pads and droids in the world, it is more of a catch up move at first glance.  Not something ms is used to.  An app store?  I can see ms's motivation, the others have it.  I gather there will not be gadgets there, go ahead and see what ms did  to the once populated gadget page...go ahead, google gadgets and take a gander, used to hundreds of gadgets, they are already gone.  They replaced gadgets?  sort of, I'll drop that, it's a bit of a sore point for me.  More of interest was what happened when I downloaded stuff off codeplex and some other normal programs that I like, like orbitron, top o' my list!!...cardware it is...anyways, click on the exe, get a screen, normal for windows, this one indicated that I was not running a normal windows program and had a button for  exit the install, naw, I hit details, a hidden run program anyways came into view....great, my path to the normal windows has detected a program tha.....yea ok, acl is on, fine, moving along I got orbitron installed in record time and was tracking the iss on the newest Microsoft OS, beta of course, felt like the first time I setup bsd all those year ago...FUN!!...I suppose I gotta start to think about budgeting for the real os when it comes out in october, by then I should have a rasberry pi and be done with fedora remixed.  Of course that sounds like fun too!!  I would use this OS on a tablet or phone.  I don't like the idea of being hearded to an app store, don't like that on anything, we are americans and want real choices not marketed hype, lest you are younger with opm (other peoples money).   This os would be neat on a zune, but I suspect the zune is a gonner, I am rooting for microsoft, after all their default password is not admin anymore, nor alpine,  it's blank. Others force a password, my first fawn password was so long I could not even log into it with the password in front of me, who the heck uses %$# anyways, and if I was writing a brute force attack what the heck kinda impasse is that anyways at .00001 microseconds of a code execution cycle (just a non qualified number, not a real clock speed)....AI is where it will be before too long, MS is on that path, perhaps soon someone will sit down and write an app for the kinect that watches your eyes while you scan the new main start screen, clicking on the big E icon when you blink.....boy is that going to be fun!!!! sure. Blink,dammit,blink,dammit...... OPM no doubt.I like windows eight, we are moving forwards, better keep a close eye on ubuntu.  The real clinch comes when open source becomes paid source......don't blink, I already see plenty of very expensive 'ix apps, some even in app stores already.  more to come.......

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• How to Recover From a Virus Infection: 3 Things You Need to Do

  - by Chris Hoffman

  If your computer becomes infected with a virus or another piece of malware, removing the malware from your computer is only the first step. There’s more you need to do to ensure you’re secure. Note that not every antivirus alert is an actual infection. If your antivirus program catches a virus before it ever gets a chance to run on your computer, you’re safe. If it catches the malware later, you have a bigger problem. Change Your Passwords You’ve probably used your computer to log into your email, online banking websites, and other important accounts. Assuming you had malware on your computer, the malware could have logged your passwords and uploaded them to a malicious third party. With just your email account, the third party could reset your passwords on other websites and gain access to almost any of your online accounts. To prevent this, you’ll want to change the passwords for your important accounts — email, online banking, and whatever other important accounts you’ve logged into from the infected computer. You should probably use another computer that you know is clean to change the passwords, just to be safe. When changing your passwords, consider using a password manager to keep track of strong, unique passwords and two-factor authentication to prevent people from logging into your important accounts even if they know your password. This will help protect you in the future. Ensure the Malware Is Actually Removed Once malware gets access to your computer and starts running, it has the ability to do many more nasty things to your computer. For example, some malware may install rootkit software and attempt to hide itself from the system. Many types of Trojans also “open the floodgates” after they’re running, downloading many different types of malware from malicious web servers to the local system. In other words, if your computer was infected, you’ll want to take extra precautions. You shouldn’t assume it’s clean just because your antivirus removed what it found. It’s probably a good idea to scan your computer with multiple antivirus products to ensure maximum detection. You may also want to run a bootable antivirus program, which runs outside of Windows. Such bootable antivirus programs will be able to detect rootkits that hide themselves from Windows and even the software running within Windows. avast! offers the ability to quickly create a bootable CD or USB drive for scanning, as do many other antivirus programs. You may also want to reinstall Windows (or use the Refresh feature on Windows 8) to get your computer back to a clean state. This is more time-consuming, especially if you don’t have good backups and can’t get back up and running quickly, but this is the only way you can have 100% confidence that your Windows system isn’t infected. It’s all a matter of how paranoid you want to be. Figure Out How the Malware Arrived If your computer became infected, the malware must have arrived somehow. You’ll want to examine your computer’s security and your habits to prevent more malware from slipping through in the same way. Windows is complex. For example, there are over 50 different types of potentially dangerous file extensions that can contain malware to keep track of. We’ve tried to cover many of the most important security practices you should be following, but here are some of the more important questions to ask: Are you using an antivirus? – If you don’t have an antivirus installed, you should. If you have Microsoft Security Essentials (known as Windows Defender on Windows 8), you may want to switch to a different antivirus like the free version of avast!. Microsoft’s antivirus product has been doing very poorly in tests. Do you have Java installed? – Java is a huge source of security problems. The majority of computers on the Internet have an out-of-date, vulnerable version of Java installed, which would allow malicious websites to install malware on your computer. If you have Java installed, uninstall it. If you actually need Java for something (like Minecraft), at least disable the Java browser plugin. If you’re not sure whether you need Java, you probably don’t. Are any browser plugins out-of-date? – Visit Mozilla’s Plugin Check website (yes, it also works in other browsers, not just Firefox) and see if you have any critically vulnerable plugins installed. If you do, ensure you update them — or uninstall them. You probably don’t need older plugins like QuickTime or RealPlayer installed on your computer, although Flash is still widely used. Are your web browser and operating system set to automatically update? – You should be installing updates for Windows via Windows Update when they appear. Modern web browsers are set to automatically update, so they should be fine — unless you went out of your way to disable automatic updates. Using out-of-date web browsers and Windows versions is dangerous. Are you being careful about what you run? – Watch out when downloading software to ensure you don’t accidentally click sketchy advertisements and download harmful software. Avoid pirated software that may be full of malware. Don’t run programs from email attachments. Be careful about what you run and where you get it from in general. If you can’t figure out how the malware arrived because everything looks okay, there’s not much more you can do. Just try to follow proper security practices. You may also want to keep an extra-close eye on your credit card statement for a while if you did any online-shopping recently. As so much malware is now related to organized crime, credit card numbers are a popular target.     

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• Corsair Hackers Reboot

  It wasn't easy for me to attend but it was absolutely worth to go. The Linux User Group of Mauritius (LUGM) organised another get-together for any open source enthusiast here on the island. Strangely named "Corsair Hackers Reboot" but it stands for a positive cause: "Corsair Hackers Reboot Event A collaborative activity involving LUGM, UoM Computer Club, Fortune Way Shopping Mall and several geeks from around the island, striving to put FOSS into homes & offices. The public is invited to discover and explore Free Software & Open Source." And it was a good opportunity for me and the kids to visit the east coast of Mauritius, too. Perfect timing It couldn't have been better... Why? Well, for two important reasons (in terms of IT): End of support for Microsoft Windows XP - 08.04.2014 Release of Ubuntu 14.04 Long Term Support - 17.04.2014 Quite funnily, those two IT dates weren't the initial reasons and only during the weeks of preparations we put those together. And therefore it was even more positive to promote the use of Linux and open source software in general to a broader audience. Getting there ... Thanks to the new motor way M3 and all the additional road work which has been completed recently it was very simple to get across the island in a very quick and relaxed manner. Compared to my trips in the early days of living in Mauritius (and riding on a scooter) it was very smooth and within less than an hour we hit Centrale de Flacq. Well, being in the city doesn't necessarily mean that one has arrived at the destination. But thanks to modern technology I had a quick look on Google Maps, and we finally managed to get a parking behind the huge bus terminal in Flacq. From there it was just a short walk to Fortune Way. The children were trying to count the number of buses... Well, lots and lots of buses - really impressive actually. What was presented? There were different areas set up. Right at the entrance one's attention was directly drawn towards the elevated hacker's stage. Similar to rock stars performing their gig there was bunch of computers, laptops and networking equipment in order to cater the right working conditions for coding/programming challenge(s) on the one hand and for the pen-testing or system hacking competition on the other hand. Personally, I was very impresses that actually Nitin took care of the pen-testing competition. He hardly started one year back with Linux in general, and Kali Linux specifically. Seeing his personal development from absolute newbie to a decent Linux system administrator within such a short period of time, is really impressive. His passion to open source software made him a living. Next, clock-wise seen, was the Kid's Corner with face-painting as the main attraction. Additionally, there were numerous paper print outs to colour. Plus a decent workstation with the educational suite GCompris. Of course, my little ones were into that. They already know GCompris since a while as they are allowed to use it on an IGEL thin client terminal here at home. To simplify my life, I set up GCompris as full-screen guest session on the server, and they can pass the login screen without any further obstacles. And because it's a thin client hooked up to a XDMCP remote session I don't have to worry about the hardware on their desk, too. The next section was the main attraction of the event: BYOD - Bring Your Own Device Well, compared to the usual context of BYOD the corsairs had a completely different intention. Here, you could bring your own laptop and a team of knowledgeable experts - read: geeks and so on - offered to fully convert your system on any Linux distribution of your choice. And even though I came later, I was told that the USB pen drives had been in permanent use. From being prepared via dd command over launching LiveCD session to finally installing a fresh Linux system on bare metal. Most interestingly, I did a similar job already a couple of months ago, while upgrading an existing Windows XP system to Xubuntu 13.10. So far, the female owner is very happy and enjoys her system almost every evening to go shopping online, checking mails, and reading latest news from the Anime world. Back to the Hackers event, Ish told me that they managed approximately 20 conversion during the day. Furthermore, Ajay and others gladly assisted some visitors with some tricky issues and by the end of the day you can call is a success. While I was around, there was a elderly male visitor that got a full-fledged system conversion to a Linux system running completely in French language. A little bit more to the centre it was Yasir's turn to demonstrate his Arduino hardware that he hooked up with an experimental electrical circuit board connected to an LCD matrix display. That's the real spirit of hacking, and he showed some minor adjustments on the fly while demo'ing the system. Also, very interesting there was a thermal sensor around. Personally, I think that platforms like the Arduino as well as the Raspberry Pi have a great potential at a very affordable price in order to bring a better understanding of electronics as well as computer programming to a broader audience. It would be great to see more of those experiments during future activities. And last but not least there were a small number of vendors. Amongst them was Emtel - once again as sponsor of the general internet connectivity - and another hardware supplier from Riche Terre shopping mall. They had a good collection of Android related gimmicks, like a autonomous web cam that can convert any TV with HDMI connector into an online video chat system given WiFi. It's actually kind of awesome to have a Skype or Google hangout video session on the big screen rather than on the laptop. Some pictures of the event LUGM: Great conversations on Linux, open source and free software during the Corsair Hackers Reboot LUGM: Educational workstation running GCompris suite attracted the youngest attendees of the day. Of course, face painting had to be done prior to hacking... LUGM: Nadim demoing some Linux specifics to interested visitors. Everyone was pretty busy during the whole day LUGM: The hacking competition, here pen-testing a wireless connection and access point between multiple machines LUGM: Well prepared workstations to be able to 'upgrade' visitors' machines to any Linux operating system Final thoughts Gratefully, during the preparations of the event I was invited to leave some comments or suggestions, and the team of the LUGM did a great job. The outdoor banner was a eye-catcher, the various flyers and posters for the event were clearly written and as far as I understood from the quick chats I had with Ish, Nadim, Nitin, Ajay, and of course others all were very happy about the event execution. Great job, LUGM! And I'm already looking forward to the next Corsair Hackers Reboot event ... Crossing fingers: Very soon and hopefully this year again :) Update: In the media The event had been announced in local media, too. L'Express: Salon informatique: Hacking Challenge à Flacq

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• ApiChange Is Released!

  - by Alois Kraus

  I have been working on little tool to simplify my life and perhaps yours as developer as well. It is basically a command line tool that allows you to execute queries on your compiled .NET code base. The main purpose is to find out how big the impact of an api change would be if you changed this or that.  Now you can do high level operations like Diff public types for breaking changes. Who uses a method? Who uses a type? Who uses implements an interface? Who references me? What format has the binary  (32/64, Managed C++, Pure IL, Unmanaged)? Search for all event subscribers and unsubscribers. A unique feature is to check for event subscription imbalances. Forgotten event subscriptions are the 90% cause of managed memory leaks. It is done at a per class level. If one class does subscribe to one event more often than it does unsubscribe it is treated as possible event subscription imbalance. Another unique ability is to search for users of string literals which allows you to track users of a string constant which is not possible otherwise. For incremental builds the ShowRebuildTargets command can be used to identify the dependant targets that need a rebuild after you did compile one assembly. It has some heuristics in place to determine the impact of breaking changes and finds out which targets need to be recompiled as well. It has a ton of other features and a an API to access these things programmatically so you can build upon these simple queries create even better tools. Perhaps we get a Visual Studio plug in? You can download it from CodePlex here. It works via XCopy deployment. Simply let it run and check the command line help out. The best feature in my opinion is that the output of nearly all commands can be piped to Excel for further analysis. Since it does read also the pdbs it can show you the source file name and line number as well for all matches. The following picture shows the output of a –WhousesType query. The following command checks where type from BaseLibraryV1.dll are used inside DependantLibV1.dll. All matches are printed out with the reason and matching item along with file and line number. There is even a hyper link to the match which will open Visual Studio. ApiChange -whousestype "*" BaseLibraryV1.dll -in DependantLibV1.dll –excel The "*” is the actual query which means all types. The syntax is the same like in C# just that placeholders are allowed ;-). More info's can be found at the Codeplex Documentation.     The tool was developed in a TDD style manner which means that it is heavily tested and already used by a quite large user base inside the company I do work for. Luckily for you I got the permission to make it public so you take advantage of it. It is fully instrumented with tracing. If you find bugs simply add the –trace command line switch to find out what is failing and send me the output. How is it done? Your first guess might be that it uses reflection. Wrong. It is based on Mono Cecil a free IL parser with a fantastic API to access all internals of a managed assembly. The speed is awesome and to make it even faster I did make the tool heavily multi threaded. The query above did execute in 1.8s with the Excel output. On a rather slow machine I can analyze over 1500 assemblies in less than 40s with a very low memory consumption. The true power of Mono Cecil is that I can load an assembly like any other data file. I have no problems unloading a file but if I would have used reflection I would need to unload a whole AppDomain just to get rid of one assembly in my memory. Just to give you a glimpse how ApiChange.Api.dll can be used I show you one of the unit tests:           public void Can_Find_GenericMethodInvocations_With_Type_Parameters()         { // 1. Create an aggregator to collect our matches             UsageQueryAggregator agg = new UsageQueryAggregator();   // 2. This is the type we want to search for. Load it via the type query             var decimalType = TypeQuery.GetTypeByName(TestConstants.MscorlibAssembly, "System.Decimal");   // 3. register the type query which searches for uses of the Decimal type             new WhoUsesType(agg, decimalType);   // 4. Search for all users of the Decimal type in the DependandLibV1Assembly             agg.Analyze(TestConstants.DependandLibV1Assembly);   // Extract matches and assert             Assert.AreEqual(2, agg.MethodMatches.Count, "Method match count");             Assert.AreEqual("UseGenericMethod", agg.MethodMatches[0].Match.Name);             Assert.AreEqual("UseGenericMethod", agg.MethodMatches[1].Match.Name);         } Many thanks go from here to Jb Evian for the creation of Mono.Cecil. Without this fantastic piece of code it would have been much much harder. There are other options around like the Common Compiler Infrastructure  Metadata Api which should do the same thing but it was not a real option since the Microsoft reader did fail on even simple assemblies (at least in September 2009 this was the case). Besides this I found the CCI Apis much harder to use. The only real competitor was Reflector which does support many things but does not let me access his cool high level analyze commands. So I decided to dig into the IL specs and as a result you can query your compiled binaries from the command line or programmatically. The best thing is you try it out for yourself and give me some feedback what you miss. If you want to contribute or have a cool idea what should be added drop me a mail at A Kraus1@___No [email protected]. There is much more inside the tool I did not talk about it (yet).

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• Fun with Aggregates

  - by Paul White

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

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• Visual Studio 2010 Productivity Tips and Tricks&ndash;Part 1: Extensions

  - by ToStringTheory

  I don’t know about you, but when it comes to development, I prefer my environment to be as free of clutter as possible.  It may surprise you to know that I have tried ReSharper, and did not like it, for the reason that I stated above.  In my opinion, it had too much clutter.  Don’t get me wrong, there were a couple of features that I did like about it (inversion of if blocks, code feedback), but for the most part, I actually felt that it was slowing me down. Introduction Another large factor besides intrusiveness/speed in my choice to dislike ReSharper would probably be that I have become comfortable with my current setup and extensions.  I believe I have a good collection, and am quite happy with what I can accomplish in a short amount of time.  I figured that I would share some of my tips/findings regarding Visual Studio productivity here, and see what you had to say. The first section of things that I would like to cover, are Visual Studio Extensions.  In case you have been living under a rock for the past several years, Extensions are available under the Tools menu in Visual Studio: The extension manager enables integrated access to the Microsoft Visual Studio Gallery online with access to a few thousand different extensions.  I have tried many extensions, but for reasons of lack reliability, usability, or features, have uninstalled almost all of them.  However, I have come across several that I find I can not do without anymore: NuGet Package Manager (Microsoft) Perspectives (Adam Driscoll) Productivity Power Tools (Microsoft) Web Essentials (Mads Kristensen) Extensions NuGet Package Manager To be honest, I debated on whether or not to put this in here.  Most people seem to have it, however, there was a time when I didn’t, and was always confused when blogs/posts would say to right click and “Add Package Reference…” which with one of the latest updates is now “Manage NuGet Packages”.  So, if you haven’t downloaded the NuGet Package Manager yet, or don’t know what it is, I would highly suggest downloading it now! Features Simply put, the NuGet Package Manager gives you a GUI and command line to access different libraries that have been uploaded to NuGet. Some of its features include: Ability to search NuGet for packages via the GUI, with information in the detail bar on the right. Quick access to see what packages are in a solution, and what packages have updates available, with easy 1-click updating. If you download a package that requires references to work on other NuGet packages, they will be downloaded and referenced automatically. Productivity Tip If you use any type of source control in Visual Studio as well as using NuGet packages, be sure to right-click on the solution and click "Enable NuGet Package Restore". What this does is add a NuGet package to the solution so that it will be checked in along side your solution, as well as automatically grab packages from NuGet on build if needed. This is an extremely simple system to use to manage your package references, instead of having to manually go into TFS and add the Packages folder. Perspectives I can't stand developing with just one monitor. Especially if it comes to debugging. The great thing about Visual Studio 2010, is that all of the panels and windows are floatable, and can dock to other screens. The only bad thing is, I don't use the same toolset with everything that I am doing. By this, I mean that I don't use all of the same windows for debugging a web application, as I do for coding a WPF application. Only thing is, Visual Studio doesn't save the screen positions for all of the undocked windows. So, I got curious one day and decided to check and see if there was an extension to help out. This is where I found Perspectives. Features Perspectives gives you the ability to configure window positions across any or your monitors, and then to save the positions in a profile. Perspectives offers a Panel to manage different presets/favorites, and a toolbar to add to the toolbars at the top of Visual Studio. Ability to 'Favorite' a profile to add it to the perspectives toolbar. Productivity Tip Take the time to setup profiles for each of your scenarios - debugging web/winforms/xaml, coding, maintenance, etc. Try to remember to use the profiles for a few days, and at the end of a week, you may find that your productivity was never better. Productivity Power Tools Ah, the Productivity Power Tools... Quite possibly one of my most used extensions, if not my most used. The tool pack gives you a variety of enhancements ranging from key shortcuts, interface tweaks, and completely new features to Visual Studio 2010. Features I don't want to bore you with all of the features here, so here are my favorite: Quick Find - Unobtrusive search box in upper-right corner of the code window. Great for searching in general, especially in a file. Solution Navigator - The 'Solution Explorer' on steroids. Easy to search for files, see defined members/properties/methods in files, and my favorite feature is the 'set as root' option. Updated 'Add Reference...' Dialog - This is probably my favorite enhancement period... The 'Add Reference...' dialog redone in a manner that resembles the Extension/Package managers. I especially love the ability to search through all of the references. "Ctrl - Click" for Definition - I am still getting used to this as I usually try to use my keyboard for everything, but I love the ability to hold Ctrl and turn property/methods/variables into hyperlinks, that you click on to see their definitions. Great for travelling down a rabbit hole in an application to research problems. While there are other commands/utilities, I find these to be the ones that I lean on the most for the usefulness. Web Essentials If you have do any type of web development in ASP .Net, ASP .Net MVC, even HTML, I highly suggest grabbing the Web Essentials right NOW! This extension alone is great for productivity in web development, and greatly decreases my development time on new features. Features Some of its best features include: CSS Previews - I say 'previews' because of the multiple kinds of previews in CSS that you get font-family, color, background/background-image previews. This is great for just tweaking UI slightly in different ways and seeing how they look in the CSS window at a glance. Live Preview - One word - awesome! This goes well with my multi-monitor setup. I put the site on one monitor in a Live Preview panel, and then as I make changes to CSS/cshtml/aspx/html, the preview window will update with each save/build automatically. For CSS, you can even turn on live-update, so as you are tweaking CSS, the style changes in real time. Great for tweaking colors or font-sizes. Outlining - Small, but I like to be able to collapse regions/declarations that are in the way of new work, or are just distracting. Commenting Shortcuts - I don't know why it wasn't included by default, but it is nice to have the key shortcuts for commenting working in the CSS editor as well. Productivity Tip When working on a site, hit CTRL-ALT-ENTER to launch the Live Preview window. Dock it to another monitor. When you make changes to the document/css, just save and glance at the other monitor. No need to alt tab, then alt tab before continuing editing. Conclusion These extensions are only the most useful and least intrusive - ones that I use every day. The great thing about Visual Studio 2010 is the extensibility options that it gives developers to utilize. Have an extension that you use that isn't intrusive, but isn't listed here? Please, feel free to comment. I love trying new things, and am always looking for new additions to my toolset of the most useful. Finally, please keep an eye out for Part 2 on key shortcuts in Visual Studio. Also, if you are visiting my site (http://tostringtheory.com || http://geekswithblogs.net/tostringtheory) from an actual browser and not a feed, please let me know what you think of the new styling!

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• Why do we (really) program to interfaces?

  - by Kyle Burns

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

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• Scheduling thread tiles with C++ AMP

  - by Daniel Moth

  This post assumes you are totally comfortable with, what some of us call, the simple model of C++ AMP, i.e. you could write your own matrix multiplication. We are now ready to explore the tiled model, which builds on top of the non-tiled one. Tiling the extent We know that when we pass a grid (which is just an extent under the covers) to the parallel_for_each call, it determines the number of threads to schedule and their index values (including dimensionality). For the single-, two-, and three- dimensional cases you can go a step further and subdivide the threads into what we call tiles of threads (others may call them thread groups). So here is a single-dimensional example: extent<1> e(20); // 20 units in a single dimension with indices from 0-19 grid<1> g(e);      // same as extent tiled_grid<4> tg = g.tile<4>(); …on the 3rd line we subdivided the single-dimensional space into 5 single-dimensional tiles each having 4 elements, and we captured that result in a concurrency::tiled_grid (a new class in amp.h). Let's move on swiftly to another example, in pictures, this time 2-dimensional: So we start on the left with a grid of a 2-dimensional extent which has 8*6=48 threads. We then have two different examples of tiling. In the first case, in the middle, we subdivide the 48 threads into tiles where each has 4*3=12 threads, hence we have 2*2=4 tiles. In the second example, on the right, we subdivide the original input into tiles where each has 2*2=4 threads, hence we have 4*3=12 tiles. Notice how you can play with the tile size and achieve different number of tiles. The numbers you pick must be such that the original total number of threads (in our example 48), remains the same, and every tile must have the same size. Of course, you still have no clue why you would do that, but stick with me. First, we should see how we can use this tiled_grid, since the parallel_for_each function that we know expects a grid. Tiled parallel_for_each and tiled_index It turns out that we have additional overloads of parallel_for_each that accept a tiled_grid instead of a grid. However, those overloads, also expect that the lambda you pass in accepts a concurrency::tiled_index (new in amp.h), not an index<N>. So how is a tiled_index different to an index? A tiled_index object, can have only 1 or 2 or 3 dimensions (matching exactly the tiled_grid), and consists of 4 index objects that are accessible via properties: global, local, tile_origin, and tile. The global index is the same as the index we know and love: the global thread ID. The local index is the local thread ID within the tile. The tile_origin index returns the global index of the thread that is at position 0,0 of this tile, and the tile index is the position of the tile in relation to the overall grid. Confused? Here is an example accompanied by a picture that hopefully clarifies things: array_view<int, 2> data(8, 6, p_my_data); parallel_for_each(data.grid.tile<2,2>(), [=] (tiled_index<2,2> t_idx) restrict(direct3d) { /* todo */ }); Given the code above and the picture on the right, what are the values of each of the 4 index objects that the t_idx variables exposes, when the lambda is executed by T (highlighted in the picture on the right)? If you can't work it out yourselves, the solution follows: t_idx.global       = index<2> (6,3) t_idx.local          = index<2> (0,1) t_idx.tile_origin = index<2> (6,2) t_idx.tile             = index<2> (3,1) Don't move on until you are comfortable with this… the picture really helps, so use it. Tiled Matrix Multiplication Example – part 1 Let's paste here the C++ AMP matrix multiplication example, bolding the lines we are going to change (can you guess what the changes will be?) 01: void MatrixMultiplyTiled_Part1(vector<float>& vC, const vector<float>& vA, const vector<float>& vB, int M, int N, int W) 02: { 03: 04: array_view<const float,2> a(M, W, vA); 05: array_view<const float,2> b(W, N, vB); 06: array_view<writeonly<float>,2> c(M, N, vC); 07: parallel_for_each(c.grid, 08: [=](index<2> idx) restrict(direct3d) { 09: 10: int row = idx[0]; int col = idx[1]; 11: float sum = 0.0f; 12: for(int i = 0; i < W; i++) 13: sum += a(row, i) * b(i, col); 14: c[idx] = sum; 15: }); 16: } To turn this into a tiled example, first we need to decide our tile size. Let's say we want each tile to be 16*16 (which assumes that we'll have at least 256 threads to process, and that c.grid.extent.size() is divisible by 256, and moreover that c.grid.extent[0] and c.grid.extent[1] are divisible by 16). So we insert at line 03 the tile size (which must be a compile time constant). 03: static const int TS = 16; ...then we need to tile the grid to have tiles where each one has 16*16 threads, so we change line 07 to be as follows 07: parallel_for_each(c.grid.tile<TS,TS>(), ...that means that our index now has to be a tiled_index with the same characteristics as the tiled_grid, so we change line 08 08: [=](tiled_index<TS, TS> t_idx) restrict(direct3d) { ...which means, without changing our core algorithm, we need to be using the global index that the tiled_index gives us access to, so we insert line 09 as follows 09: index<2> idx = t_idx.global; ...and now this code just works and it is tiled! Closing thoughts on part 1 The process we followed just shows the mechanical transformation that can take place from the simple model to the tiled model (think of this as step 1). In fact, when we wrote the matrix multiplication example originally, the compiler was doing this mechanical transformation under the covers for us (and it has additional smarts to deal with the cases where the total number of threads scheduled cannot be divisible by the tile size). The point is that the thread scheduling is always tiled, even when you use the non-tiled model. But with this mechanical transformation, we haven't gained anything… Hint: our goal with explicitly using the tiled model is to gain even more performance. In the next post, we'll evolve this further (beyond what the compiler can automatically do for us, in this first release), so you can see the full usage of the tiled model and its benefits… Comments about this post by Daniel Moth welcome at the original blog.

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• Google Analytics on Android

  - by pjv

  There is a specific and official analytics SDK for native Android apps (note that I'm not talking about webpages in apps on a phone). This library basically sends pages and events to Google Analytics and you can view your analytics in exactly the same dashboard as for websites. Since my background is apps rather than websites, and since a lot of the Google Analytics terminology seems particularly inapplicable to a native app, I need some pointers. Please discuss my remarks, provide some clarification where you think I'm off-track, and above all share good experiences! 1. Page Views Pages mostly can match different Activities (and Dialogs) being displayed. Activities can be visible behind non-full-screen Activities however, though only the top-level Activity can be interacted. This sort-off clashes with a "(page) view". You'd also want at least one page view for each visit and therefore put one page view tracker in the Application class. However this does not constitute a window or sorts. Usually an Activity will open at the same time, so the time spent on that page will have been 0. This will influence your "time spent" statistics. How are these counted anyway? Moreover, there is a loose coupling between the Activities, by means of Intents. A user can, much like on any website, step in at any Activity, although usually this then concerns resuming the application where he left off. This makes that the hierarchy of Activities usually is very flat. And since there are no url's involved. What meaning would using slashes in page titles have, such as "/Home"? All pages would appear on an equal level in the reports, so no content drilldown. Non-unique page views seem to be counted as some kind of indicator of successfulness: how often does the visitor revisit the page. When the user rotates the screen however usually an Activity resumes again, thus making it a new page view. This happens a lot. Maybe a well-thought-through placement of the call might solve this, or placing several, I'm not sure. How to deal with Page Views? 2. Events I'd say there are two sorts: A user event Something that happened, usually as an indirect consequence of the above. The latter particularly is giving me headaches. First of all, many events aren't written in code any more, but pieced logically together by means of Intents. This means that there is no place to put the analytics call. You'd either have to give up this advantage and start doing it the old-fashioned way in favor of good analytics, or, just be missing some events. Secondly, as a developer you're not so much interested in when a user clicks a button, but if the action that should have been performed really was performed and what the result was. There seems to be no clear way to get resulting data into Google Analytics (what's up with the integers? I want to put in Strings!). The same that applies to the flat pages hierarchy, also goes for the event categories. You could do "vertical" categories (topically, that is), but some code is shared "horizontally" and the tracking will be equally shared. Just as with the Intents mechanism, inheritance makes it hard for you to put the tracking in the right places at all times. And I can't really imagine "horizontal" categories. Unless you start making really small categories, such as all the items form the same menu in one category, I have a hard time grasping the concept. Finally, how do you deal with cancelling? Usually you both have an explicit cancel mechanism by ways of a button, as well as the implicit cancel when the "back"-button is pressed to leave the activity and there were no changes. The latter also applies to "saves", when the back button is pressed and there ARE changes. How are you consequently going to catch all these if not by doing all the "back"-button work yourself? How to deal with events? 3. Goals For goal types I have choice of: URL Destination, Time on Site, and Pages/Visit. Most apps don't have a funnel that leads the user to some "registration done" or "order placed" page. Apps have either already been bought (in which case you want to stimulate the user to love your app, so that he might bring on new buyers) or are paid for by in-app ads. So URL Destination is not a very important goal. Time on Site also seems troublesome. First, I have some doubt on how this would be measured. Second, I don't necessarily want my user to spend a lot of time in my already paid app, just be active and content. Equivalently, why not mention how frequent a user uses your app? Regarding Pages/Visit I already mentioned how screen orientation changes blow up the page view numbers. In an app I'd be most interested in events/visit to measure the user's involvement/activity. If he's intensively using the app then he must be loving it right? Furthermore, I also have some small funnels (that do not lead to conversion though) that I want to see streamlined. In my mind those funnels would end in events rather than page views but that seems not to be possible. I could also measure clickthroughs on in-app ads, but then I'd need to track those as Page Views rather than Events, in view of "URL Destination". What are smart goals for apps and how can you fit them on top of Analytics? 4. Optimisation Is there a smart way to manually do what "Website Optimiser" does for websites? Most importantly, how would I track different landing page designs? 5. Traffic Sources Referrals deal with installation time referrals, if you're smart enough to get them included. But perhaps I'd also want to get some data which third-party app sends users to my app to perform some actions (this app interoperability is possible via Intents). Many of the terminologies related to "Traffic Sources" seem totally meaningless and there is no possibility of connecting in AdSense. What are smart uses of this data? 6. Visitors Of the "Browser capabilities", "Network Properties" and "Mobile" tabs, many things are pointless as they have no influence on / relation with my mostly offline app that won't use flash anyway. Only if you drill down far enough, can you get to OS versions, which do matter a lot. I even forgot where you could check what exact Android devices visited. What are smart uses of this data? How can you make the relevant info more prominent? 7. Other No in-page analytics. I have to register my app as a web-url (What!?)?

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• Silverlight IConvertible TypeConverter

  - by codingbloke

  I recently answered the following question on stackoverflow:  Silverlight 3 custom control: only ‘int’ as numeric type for a property? [e.g. long or int64 seems to break] I quickly knocked up the class ConvertibleTypeConverter<T> that I posted in the question (listed later here as well). Afterward I fully expected to find that of the usual clever “bods who blog” to have covered this probably with a better solution than I.  So far though I’ve not found one so I thought I’d blog it myself. The Problem Here is a classic gotcha I’ve seen asked more than once on stackoverflow :- public class MyClass {     public float SomeValue { get; set; } } <local:MyClass SomeValue="45.15" /> This fails with the error  “Failed to create a 'System.Single' from the text '45.15'”  and results in much premature hair loss.  Fortunately this is SL4, in SL3 the error message is almost meaningless.  So what gives, how can it be that this fails when we can see other very similar values parsing happily all over the place? It comes down the fact that the Xaml parser only handles a few of the primitive data types namely: bool, int, string and double.  Since the parser has no idea how to convert a string to a float we get the above error. The Solution The sensible solution is “use double not float” but lets not dwell on that, there has to be occasions where such an answer isn’t acceptable. In order to achieve parsing of other types we need an implementation of TypeConverter for the type of the property and then we need to use the TypeConverterAttribute to decorate the property .  As an example the Silverlight SDK provides one for DateTime the DateTimeTypeConverter (yes I know DateTime isn’t really a primitive). The following class will parse in Xaml:- public class MyClass {     [TypeConverter(typeof(DateTimeTypeConverter))]     public DateTime SomeValue {get; set; } } So far though we would need to create a TypeConverter for each primitive type we are using, what if I had the following mad class to support in Xaml:- public class StrangePrimitives {     public Boolean BooleanProp { get; set; }     public Byte ByteProp { get; set; }     public Char CharProp { get; set; }     public DateTime DateTimeProp { get; set; }     public Decimal DecimalProp { get; set; }     public Double DoubleProp { get; set; }     public Int16 Int16Prop { get; set; }     public Int32 Int32Prop { get; set; }     public Int64 Int64Prop { get; set; }     public SByte SByteProp { get; set; }     public Single SingleProp { get; set; }     public String StringProp { get; set; }     public UInt16 UInt16Prop { get; set; }     public UInt32 UInt32Prop { get; set; }     public UInt64 UInt64Prop { get; set; } } Then I want to fill an instance of StrangePrimitives with the following Xaml which of course fails. <local:StrangePrimitives x:Key="MyStrangePrimitives"                          BooleanProp="True"                          ByteProp="156"                          CharProp="A"                          DateTimeProp="06 Jun 2010"                          DecimalProp="123.56"                          DoubleProp="8372.937803"                          Int16Prop="16532"                          Int32Prop="73738248"                          Int64Prop="12345678909298"                          SByteProp="-123"                          SingleProp="39.0"                          StringProp="Hello, World!"                          UInt16Prop="40000"                          UInt32Prop="4294967295"                          UInt64Prop="18446744073709551615"      /> I got to thinking, though, one thing all these primitive types have in common is that they all implement IConvertible so it should be possible to write just one converter to handle them all.  Here it is:- The ConvertibleTypeConverter public class ConvertibleTypeConverter<T> : TypeConverter where T : IConvertible {     public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)     {         return sourceType.GetInterface("IConvertible", false) != null;     }     public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType)     {         return destinationType.GetInterface("IConvertible", false) != null;     }     public override object ConvertFrom(ITypeDescriptorContext context, System.Globalization.CultureInfo culture, object value)     {         return ((IConvertible)value).ToType(typeof(T), culture);     }     public override object ConvertTo(ITypeDescriptorContext context, System.Globalization.CultureInfo culture, object value, Type destinationType)     {         return ((IConvertible)value).ToType(destinationType, culture);     } } I won’t bore you with an explanation of how it works, it simply adapts one existing interface (the IConvertible) and exposes it as another (the TypeConverter).   With that in place the previous strange primitives class can be modified as:- public class StrangePrimitives {     public Boolean BooleanProp { get; set; }     [TypeConverter(typeof(ConvertibleTypeConverter<Byte>))]     public Byte ByteProp { get; set; }     [TypeConverter(typeof(ConvertibleTypeConverter<Char>))]     public Char CharProp { get; set; }     [TypeConverter(typeof(ConvertibleTypeConverter<DateTime>))]     public DateTime DateTimeProp { get; set; }     [TypeConverter(typeof(ConvertibleTypeConverter<Decimal>))]     public Decimal DecimalProp { get; set; }     public Double DoubleProp {get; set; }     [TypeConverter(typeof(ConvertibleTypeConverter<Int16>))]     public Int16 Int16Prop { get; set; }     public Int32 Int32Prop { get; set; }     [TypeConverter(typeof(ConvertibleTypeConverter<Int64>))]     public Int64 Int64Prop { get; set; }     [TypeConverter(typeof(ConvertibleTypeConverter<SByte>))]     public SByte SByteProp { get; set; }     [TypeConverter(typeof(ConvertibleTypeConverter<Single>))]     public Single SingleProp { get; set; }     public String StringProp { get; set; }     [TypeConverter(typeof(ConvertibleTypeConverter<UInt16>))]     public UInt16 UInt16Prop { get; set; }     [TypeConverter(typeof(ConvertibleTypeConverter<UInt32>))]     public UInt32 UInt32Prop { get; set; }     [TypeConverter(typeof(ConvertibleTypeConverter<UInt64>))]     public UInt64 UInt64Prop { get; set; } } This results in the previous Xaml parsing happily.  Now it seems such an obvious thing to do that one may wonder why such a class doesn’t already existing in Silverlight or at least in the SDK.   I would not be surprised if there were some very good reasons hence use the ConvertibleTypeConverter with caution.  It does seem to me to be a useful little class to have lying around in the toolbox for the odd occasion where it may be needed.

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• GLSL compiler messages from different vendors [on hold]

  - by revers

  I'm writing a GLSL shader editor and I want to parse GLSL compiler messages to make hyperlinks to invalid lines in a shader code. I know that these messages are vendor specific but currently I have access only to AMD's video cards. I want to handle at least NVidia's and Intel's hardware, apart from AMD's. If you have video card from different vendor than AMD, could you please give me the output of following C++ program: #include <GL/glew.h> #include <GL/freeglut.h> #include <iostream> using namespace std; #define STRINGIFY(X) #X static const char* fs = STRINGIFY( out vec4 out_Color; mat4 m; void main() { vec3 v3 = vec3(1.0); vec2 v2 = v3; out_Color = vec4(5.0 * v2.x, 1.0); vec3 k = 3.0; float = 5; } ); static const char* vs = STRINGIFY( in vec3 in_Position; void main() { vec3 v(5); gl_Position = vec4(in_Position, 1.0); } ); void printShaderInfoLog(GLint shader) { int infoLogLen = 0; int charsWritten = 0; GLchar *infoLog; glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &infoLogLen); if (infoLogLen > 0) { infoLog = new GLchar[infoLogLen]; glGetShaderInfoLog(shader, infoLogLen, &charsWritten, infoLog); cout << "Log:\n" << infoLog << endl; delete [] infoLog; } } void printProgramInfoLog(GLint program) { int infoLogLen = 0; int charsWritten = 0; GLchar *infoLog; glGetProgramiv(program, GL_INFO_LOG_LENGTH, &infoLogLen); if (infoLogLen > 0) { infoLog = new GLchar[infoLogLen]; glGetProgramInfoLog(program, infoLogLen, &charsWritten, infoLog); cout << "Program log:\n" << infoLog << endl; delete [] infoLog; } } void initShaders() { GLuint v = glCreateShader(GL_VERTEX_SHADER); GLuint f = glCreateShader(GL_FRAGMENT_SHADER); GLint vlen = strlen(vs); GLint flen = strlen(fs); glShaderSource(v, 1, &vs, &vlen); glShaderSource(f, 1, &fs, &flen); GLint compiled; glCompileShader(v); bool succ = true; glGetShaderiv(v, GL_COMPILE_STATUS, &compiled); if (!compiled) { cout << "Vertex shader not compiled." << endl; succ = false; } printShaderInfoLog(v); glCompileShader(f); glGetShaderiv(f, GL_COMPILE_STATUS, &compiled); if (!compiled) { cout << "Fragment shader not compiled." << endl; succ = false; } printShaderInfoLog(f); GLuint p = glCreateProgram(); glAttachShader(p, v); glAttachShader(p, f); glLinkProgram(p); glUseProgram(p); printProgramInfoLog(p); if (!succ) { exit(-1); } delete [] vs; delete [] fs; } int main(int argc, char* argv[]) { glutInit(&argc, argv); glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGBA); glutInitWindowSize(600, 600); glutCreateWindow("Triangle Test"); glewInit(); GLenum err = glewInit(); if (GLEW_OK != err) { cout << "glewInit failed, aborting." << endl; exit(1); } cout << "Using GLEW " << glewGetString(GLEW_VERSION) << endl; const GLubyte* renderer = glGetString(GL_RENDERER); const GLubyte* vendor = glGetString(GL_VENDOR); const GLubyte* version = glGetString(GL_VERSION); const GLubyte* glslVersion = glGetString(GL_SHADING_LANGUAGE_VERSION); GLint major, minor; glGetIntegerv(GL_MAJOR_VERSION, &major); glGetIntegerv(GL_MINOR_VERSION, &minor); cout << "GL Vendor : " << vendor << endl; cout << "GL Renderer : " << renderer << endl; cout << "GL Version : " << version << endl; cout << "GL Version : " << major << "." << minor << endl; cout << "GLSL Version : " << glslVersion << endl; initShaders(); return 0; } On my video card it gives: Status: Using GLEW 1.7.0 GL Vendor : ATI Technologies Inc. GL Renderer : ATI Radeon HD 4250 GL Version : 3.3.11631 Compatibility Profile Context GL Version : 3.3 GLSL Version : 3.30 Vertex shader not compiled. Log: Vertex shader failed to compile with the following errors: ERROR: 0:1: error(#132) Syntax error: '5' parse error ERROR: error(#273) 1 compilation errors. No code generated Fragment shader not compiled. Log: Fragment shader failed to compile with the following errors: WARNING: 0:1: warning(#402) Implicit truncation of vector from size 3 to size 2. ERROR: 0:1: error(#174) Not enough data provided for construction constructor WARNING: 0:1: warning(#402) Implicit truncation of vector from size 1 to size 3. ERROR: 0:1: error(#132) Syntax error: '=' parse error ERROR: error(#273) 2 compilation errors. No code generated Program log: Vertex and Fragment shader(s) were not successfully compiled before glLinkProgram() was called. Link failed. Or if you like, you could give me other compiler messages than proposed by me. To summarize, the question is: What are GLSL compiler messages formats (INFOs, WARNINGs, ERRORs) for different vendors? Please give me examples or pattern explanation. EDIT: Ok, it seems that this question is too broad, then shortly: How does NVidia's and Intel's GLSL compilers present ERROR and WARNING messages? AMD/ATI uses patterns like this: ERROR: <position>:<line_number>: <message> WARNING: <position>:<line_number>: <message> (examples are above).

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• PASS Summit – looking back on my first time

  - by Fatherjack

    So I was lucky enough to get my first experience of PASS Summit this year and took some time beforehand to read some blogs and reference material to get an idea on what to do and how to get the best out of my visit. Having been to other conferences – technical and non-technical – I had a reasonable idea on the routine and what to expect in general. Here is a list of a few things that I have learned/remembered as the week has gone by. Wear comfortable shoes. This actually needs to be broadened to Take several pairs of comfortable shoes. You will be spending many many hours, for several days one after another. Having comfortable feet that can literally support you for the duration will make the week in general a whole lot better. Not only at the conference but getting to and from you could well be walking. In the evenings you will be walking around town and standing talking in various bars and clubs. Looking back, on some days I was on my feet for over 20 hours. Make friends. This is a given for the long term benefits it brings but there is also an immediate reward in being at a conference with a friend or two. Some events are bigger and more popular than others and some have the type of session that every single attendee will want to be in. This is great for those that get in but if you are in the bathroom or queuing for coffee and you miss out it sucks. Having a friend that can get in to a room and reserve you a seat is a great advantage to make sure you get the content that you want to see and still have the coffee that you need. Don’t go to every session you want to see This might sound counter intuitive and it relies on the sessions being recorded in some way to guarantee you don’t totally miss out. Both PASS Summit and SQL Bits sessions are recorded (summit is audio, SQLBits is video) and this means that if you get into a good conversation with someone over a coffee you don’t have to break it up to go to a session. Obviously there is a trade-off here and you need to decide on the tipping point for yourself but a conversation at a place like this could make a big difference to the next contract or employer you have or it might simply be great catching up with some friends you don’t see so often. Go to at least one session you don’t want to Again, this will seem to be contrary to normal logic but there is no reason why you shouldn’t learn about a part of SQL Server that isn’t part of your daily routine. Not only will you learn something new but you will also pick up on the feelings and attitudes of the people in the session. So, if you are a DBA, head off to a BI session and so on. You’ll hear BI speakers speaking to a BI audience and get to understand their point of view and reasoning for making the decisions they do. You will also appreciate the way that your decisions and instructions affect the way they have to work. This will help you a lot when you are on a project, working with multiple teams and make you all more productive. Socialise While you are at the conference venue, speak to people. Ask questions, be interested in whoever you are speaking to. You get chances to talk to new friends at breakfast, dinner and every break between sessions. The only people that might not talk to you would be speakers that are about to go and give a session, in most cases speakers like peace and quiet before going on stage. Other than that the people around you are just waiting for someone to talk to them so make the first move. There is a whole lot going on outside of the conference hours and you should make an effort to join in with some of this too. At karaoke evenings or just out for a quiet drink with a few of the people you meet at the conference. Either way, don’t be a recluse and hide in your room or be alone out in the town. Don’t talk to people Once again this sounds wrong but stay with me. I have spoken to a number of speakers since Summit 2013 finished and they have all mentioned the time it has taken them to move about the conference venue due to people stopping them for a chat or to ask a question. 45 minutes to walk from a session room to the speaker room in one case. Wow. While none of the speakers were upset about this sort of delay I think delegates should take the situation into account and possibly defer their question to an email or to a time when the person they want is clearly less in demand. Give them a chance to enjoy the conference in the same way that you are, they may actually want to go to a session or just have a rest after giving their session – talking for 75 minutes is hard work, taking an extra 45 minutes right after is unbelievable. I certainly hope that they get good feedback on their sessions and perhaps if you spoke to a speaker outside a session you can give them a mention in the ‘any other comments’ part of the feedback, just to convey your gratitude for them giving up their time and expertise for free. Say thank you I just mentioned giving the speakers a clear, visible ‘thank you’ in the feedback but there are plenty of people that help make any conference the success it is that would really appreciate hearing that their efforts are valued. People on the registration desk, volunteers giving schedule guidance and directions, people on the community zone are all volunteers giving their time to help you have the best experience possible. Send an email to PASS and convey your thoughts about the work that was done. Maybe you want to be a volunteer next time so you could enquire how you get into that position at the same time. This isn’t an exclusive list and you may agree or disagree with the points I have made, please add anything you think is good advice in the comments. I’d like to finish by saying a huge thank you to all the people involved in planning, facilitating and executing the PASS Summit 2013, it was an excellent event and I know many others think it was a totally worthwhile event to attend.

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• First PC Build (Part 1)

  - by Anthony Trudeau

  Originally posted on: http://geekswithblogs.net/tonyt/archive/2014/08/05/157959.aspxA couple of months ago I made the decision to build myself a new computer. The intended use is gaming and for using the last real version of Photoshop. I was motivated by the poor state of console gaming and a simple desire to do something I haven’t done before – build a PC from the ground up. I’ve been using PCs for more than two decades. I’ve replaced a component hear and there, but for the last 10 years or so I’ve only used laptops. Therefore, this article will be written from the perspective of someone familiar with PCs, but completely new at building. I’m not an expert and this is not a definitive guide for building a PC, but I do hope that it encourages you to try it yourself. Component List Research There was a lot of research necessary, because building a PC is completely new to me, and I haven’t kept up with what’s out there. The first thing you want to do is nail down what your goals are. Your goals are going to be driven by what you want to do with your computer and personal choice. Don’t neglect the second one, because if you’re doing this for fun you want to get what you want. In my case, I focused on three things: performance, longevity, and aesthetics. The performance aspect is important for gaming and Photoshop. This will drive what components you get. For example, heavy gaming use is going to drive your choice of graphics card. Longevity is relevant to me, because I don’t want to be changing things out anytime soon for the next hot game. The consequence of performance and longevity is cost. Finally, aesthetics was my next consideration. I could have just built a box, but it wouldn’t have been nearly as fun for me. Aesthetics might not be important to you. They are for me. I also like gadgets and that played into at least one purchase for this build. I used PC Part Picker to put together my component list. I found it invaluable during the process and I’d recommend it to everyone. One caveat is that I wouldn’t trust the compatibility aspects. It does a pretty good job of not steering you wrong, but do your own research. The rest of it isn’t really sexy. I started out with what appealed to me and then I made changes and additions as I dived deep into researching each component and interaction I could find. The resources I used are innumerable. I used reviews, product descriptions, forum posts (praises and problems), et al. to assist me. I also asked friends into gaming what they thought about my component list. And when I got near the end I posted my list to the Reddit /r/buildapc forum. I cannot stress the value of extra sets of eyeballs and first hand experiences. Some of the resources I used: PC Part Picker Tom’s Hardware bit-tech Reddit Purchase PC Part Picker favors certain vendors. You should look at others too. In my case I found their favorites to be the best. My priorities were out-the-door price and shipping time. I knew that once I started getting parts I’d want to start building. Luckily, I timed it well and everything arrived within the span of a few days. Here are my opinions on the vendors I ended up using in alphabetical order. Amazon.com is a good, reliable choice. They have excellent customer service in my experience, and I knew I wouldn’t have trouble with them. However, shipping time is often a problem when you use their free shipping unless you order expensive items (I’ve found items over $100 ship quickly). Ultimately though, price wasn’t always the best and their collection of sales tax in my state turned me off them. I did purchase my case from them. I ordered the mouse as well, but I cancelled after it was stuck four days in a “shipping soon” state. I purchased the mouse locally. Best Buy is not my favorite place to do business. There’s a lot of history with poor, uninterested sales representatives and they used to have a lot of bad anti-consumer policies. That’s a lot better now, but the bad taste is still in my mouth. I ended up purchasing the accessories from them including mouse (locally) and headphones. NCIX is a company that I’ve never heard of before. It popped up as a recommendation for my CPU cooler on PC Part Picker. I didn’t do a lot of research on the company, because their policy on you buying insurance for your orders turned me off. That policy makes it clear to me that the company finds me responsible for the shipment once it leaves their dock. That’s not right, and may run afoul of state laws. Regardless they shipped my CPU cooler quickly and I didn’t have a problem. NewEgg.com is a well known company. I had never done business with them, but I’m glad I did. They shipped quickly and provided good visibility over everything. The prices were also the best in most cases. My main complaint is that they have a lot of exchange only return policies on components. To their credit those policies are listed in the cart underneath each item. The visibility tells me that they’re not playing any shenanigans and made me comfortable dealing with that risk. The vast majority of what I ordered came from them. Coming Next In the next part I’ll tackle my build experience.

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• Alcatel-Lucent: Enterprise 2.0: The Top 5 Things I would Do Over

  - by Kellsey Ruppel

  Happy Monday! Does anyone else feel as if the weekend went entirely too quickly? At least for those of us in the United States, we have the 4th of July Holiday next week to look forward to This week on the blog, we are going to focus on "WebCenter by Example" and highlight best practices from customers and partners. I recently came across this article and I think this is a great example of how we can learn from one another when it comes to social collaboration adoption. Do you agree with Jem? What things or best practices have you learned in your organizations?  By Jem Janik, Enterprise community manager, Alcatel-Lucent  Not so long ago, Engage, the Alcatel-Lucent employee social network and collaboration platform, celebrated its third birthday. With more than 25,000 members actively interacting each month, Engage has been a big enough success that it’s been the subject of external articles, and often those of us who helped launch it will go out and speak about what aspects contributed to that success. Hindsight is still 20/20 and what it takes to successfully launch an enterprise 2.0 community is fairly well-known now.  Today I want to tell you what I suspect you really want to know about.  As the enterprise community manager for Engage, after three years in, what are the top 5 things I wish we (and I mostly mean me) could do over? #5 Define your analytics solution from the start There is so much to do when you launch a community and initially growing it without complete chaos is quite a task.  It doesn’t take too long to get to a point where you want to focus your continued efforts in growing company collaboration.  Do people truly talk across regional boundaries or have we shifted siloed conversations to a new platform.  Is there one organization that doesn’t interact with another? If you are lucky you’ll have someone in your community team well versed in the world of databases and SQL queries, but it takes time to figure out what backend analytics data actually means. Professional support can be expensive and it may be hard to justify later as it typically has the community manager as the only main customer.  Figure out what you think you’ll want to know and how to get it early on. The sooner the better even if it doesn’t seem that critical at the time. #4 Lobbies guide you to the right places One piece of feedback that comes up more and more as we keep growing Engage is it’s hard to find stuff, or new people are not sure where to start. Something we’re doing now is defining some general topic areas of interest to be like “lobbies” into the platform and some common hashtags to go with them. I liken this to walking into a large medical or professional building for the first time.  There are hundreds of offices, and you look to a sign in the lobby to get guided to the right place for you.  We’re building that sign for members now, but again we missed the boat as the majority of the company has had their initial Engage experience. #3 Clean up, clean up, clean up Knowledge work and folksonomies are messy! The day we opened the doors to Engage I would have said we should keep everything ever created in Engage with an argument that it was a window into our collective knowledge so nothing should go.  Well, 6000+ groups and 200,000+ pieces of content later, I’ve changed my mind.  As previously mentioned, with too much “stuff” the system can be overwhelming to new members and it makes it harder to get what you’re looking for.   Do we need that help document about a tool we no longer have? NO!  Do we need that group that had 1 document and 2 discussions in the last two years? NO! Should we only have one group about a given topic instead of 4?  YES! Last fall, Engage defined a cleanup process for groups not used for a long time.  We also formed a volunteer cleaning army who are extra eyes on the hunt for “stuff” that should be updated, merged, or deleted.  It’s better late than never, but in line with what’s becoming a theme I wish these efforts had started earlier. #2 Communications & local community management One of the most important aspects of my job is to make sure people who should be talking to each other are actually doing it.  Connecting people to the other people they should know, the groups they should join, a piece of content that shouldn’t be missed.   I have worked both inside and outside of communications teams, and they are the best informed people in your company.  They know when something big is coming, how it impacts employees, how it fits with strategy, who else knows more, etc.  Having communications professionals who are power users can help scale up community management because they are already so well connected.  They also need to have the platform skills to pay attention without suffering email overload, how to grab someone’s attention, etc.  I wish I’d had figured this out much earlier.  If I had I would have groomed more communications colleagues into advocates and power members right at the start. #1 Grooming advocates vs. natural advocates I’ve just alluded to this above already. The very best advocates are those who naturally embrace your platform and automatically start to see new ways to work within it.  Those advocates seem to come out of the woodwork naturally since some of them are early adopters.  Not surprisingly, our best advocates today are those same people who were willing to come kick the tires when the community was completely empty.  Unfortunately, we didn’t get a global spread of those natural advocates.  I did ask around when we first launched for other people who might be good candidates, but didn’t push too hard as there were so many other things to get ready.  That was a mistake.  If I could get a redo I would have formally asked for people to be assigned where there were gaps and groomed them into an advocate.  Today as we find new advocates to fill the gaps, people are hesitant as the initial set has three years of practice are ahead of the curve power members; it definitely would have been easier earlier on. As fairly early adopters to corporate scale enterprise collaboration, there hasn’t been a roadmap to follow as we’ve grown Engage, which is part of the fun! It’s clear a lot of issues are more easily tackled the earlier you identify and begin to correct them, and I’ve identified the main five I wish I could redo.  In the spirit of collaboration, I hope someone else learns from my mistakes! View the original article by Jem here. 

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• Metrics - A little knowledge can be a dangerous thing (or 'Why you're not clever enough to interpret metrics data')

  - by Jason Crease

  At RedGate Software, I work on a .NET obfuscator  called SmartAssembly.  Various features of it use a database to store various things (exception reports, name-mappings, etc.) The user is given the option of using either a SQL-Server database (which requires them to have Microsoft SQL Server), or a Microsoft Access MDB file (which requires nothing). MDB is the default option, but power-users soon switch to using a SQL Server database because it offers better performance and data-sharing. In the fashionable spirit of optimization and metrics, an obvious product-management question is 'Which is the most popular? SQL Server or MDB?' We've collected data about this fact, using our 'Feature-Usage-Reporting' technology (available as part of SmartAssembly) and more recently our 'Application Metrics' technology: Parameter Number of users % of total users Number of sessions Number of usages SQL Server 28 19.0 8115 8115 MDB 114 77.6 1449 1449 (As a disclaimer, please note than SmartAssembly has far more than 132 users . This data is just a selection of one build) So, it would appear that SQL-Server is used by fewer users, but more often. Great. But here's why these numbers are useless to me: Only the original developers understand the data What does a single 'usage' of 'MDB' mean? Does this happen once per run? Once per option change? On clicking the 'Obfuscate Now' button? When running the command-line version or just from the UI version? Each question could skew the data 10-fold either way, and the answers only known by the developer that instrumented the application in the first place. In other words, only the original developer can interpret the data - product-managers cannot interpret the data unaided. Most of the data is from uninterested users About half of people who download and run a free-trial from the internet quit it almost immediately. Only a small fraction use it sufficiently to make informed choices. Since the MDB option is the default one, we don't know how many of those 114 were people CHOOSING to use the MDB, or how many were JUST HAPPENING to use this MDB default for their 20-second trial. This is a problem we see across all our metrics: Are people are using X because it's the default or are they using X because they want to use X? We need to segment the data further - asking what percentage of each percentage meet our criteria for an 'established user' or 'informed user'. You end up spending hours writing sophisticated and dubious SQL queries to segment the data further. Not fun. You can't find out why they used this feature Metrics can answer the when and what, but not the why. Why did people use feature X? If you're anything like me, you often click on random buttons in unfamiliar applications just to explore the feature-set. If we listened uncritically to metrics at RedGate, we would eliminate the most-important and more-complex features which people actually buy the software for, leaving just big buttons on the main page and the About-Box. "Ah, that's interesting!" rather than "Ah, that's actionable!" People do love data. Did you know you eat 1201 chickens in a lifetime? But just 4 cows? Interesting, but useless. Often metrics give you a nice number: '5.8% of users have 3 or more monitors' . But unless the statistic is both SUPRISING and ACTIONABLE, it's useless. Most metrics are collected, reviewed with lots of cooing. and then forgotten. Unless a piece-of-data could change things, it's useless collecting it. People get obsessed with significance levels The first things that lots of people do with this data is do a t-test to get a significance level ("Hey! We know with 99.64% confidence that people prefer SQL Server to MDBs!") Believe me: other causes of error/misinterpretation in your data are FAR more significant than your t-test could ever comprehend. Confirmation bias prevents objectivity If the data appears to match our instinct, we feel satisfied and move on. If it doesn't, we suspect the data and dig deeper, plummeting down a rabbit-hole of segmentation and filtering until we give-up and move-on. Data is only useful if it can change our preconceptions. Do you trust this dodgy data more than your own understanding, knowledge and intelligence?  I don't. There's always multiple plausible ways to interpret/action any data Let's say we segment the above data, and get this data: Post-trial users (i.e. those using a paid version after the 14-day free-trial is over): Parameter Number of users % of total users Number of sessions Number of usages SQL Server 13 9.0 1115 1115 MDB 5 4.2 449 449 Trial users: Parameter Number of users % of total users Number of sessions Number of usages SQL Server 15 10.0 7000 7000 MDB 114 77.6 1000 1000 How do you interpret this data? It's one of: Mostly SQL Server users buy our software. People who can't afford SQL Server tend to be unable to afford or unwilling to buy our software. Therefore, ditch MDB-support. Our MDB support is so poor and buggy that our massive MDB user-base doesn't buy it.  Therefore, spend loads of money improving it, and think about ditching SQL-Server support. People 'graduate' naturally from MDB to SQL Server as they use the software more. Things are fine the way they are. We're marketing the tool wrong. The large number of MDB users represent uninformed downloaders. Tell marketing to aggressively target SQL Server users. To choose an interpretation you need to segment again. And again. And again, and again. Opting-out is correlated with feature-usage Metrics tends to be opt-in. This skews the data even further. Between 5% and 30% of people choose to opt-in to metrics (often called 'customer improvement program' or something like that). Casual trial-users who are uninterested in your product or company are less likely to opt-in. This group is probably also likely to be MDB users. How much does this skew your data by? Who knows? It's not all doom and gloom. There are some things metrics can answer well. Environment facts. How many people have 3 monitors? Have Windows 7? Have .NET 4 installed? Have Japanese Windows? Minor optimizations.  Is the text-box big enough for average user-input? Performance data. How long does our app take to start? How many databases does the average user have on their server? As you can see, questions about who-the-user-is rather than what-the-user-does are easier to answer and action. Conclusion Use SmartAssembly. If not for the metrics (called 'Feature-Usage-Reporting'), then at least for the obfuscation/error-reporting. Data raises more questions than it answers. Questions about environment are the easiest to answer.

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• Using IIS Logs for Performance Testing with Visual Studio

  - by Tarun Arora

  In this blog post I’ll show you how you can play back the IIS Logs in Visual Studio to automatically generate the web performance tests. You can also download the sample solution I am demo-ing in the blog post. Introduction Performance testing is as important for new websites as it is for evolving websites. If you already have your website running in production you could mine the information available in IIS logs to analyse the dense zones (most used pages) and performance test those pages rather than wasting time testing & tuning the least used pages in your application. What are IIS Logs To help with server use and analysis, IIS is integrated with several types of log files. These log file formats provide information on a range of websites and specific statistics, including Internet Protocol (IP) addresses, user information and site visits as well as dates, times and queries. If you are using IIS 7 and above you will find the log files in the following directory C:\Interpub\Logs\ Walkthrough 1. Download and Install Log Parser from the Microsoft download Centre. You should see the LogParser.dll in the install folder, the default install location is C:\Program Files (x86)\Log Parser 2.2. LogParser.dll gives us a library to query the iis log files programmatically. By the way if you haven’t used Log Parser in the past, it is a is a powerful, versatile tool that provides universal query access to text-based data such as log files, XML files and CSV files, as well as key data sources on the Windows operating system such as the Event Log, the Registry, the file system, and Active Directory. More details… 2. Create a new test project in Visual Studio. Let’s call it IISLogsToWebPerfTestDemo.   3.  Delete the UnitTest1.cs class that gets created by default. Right click the solution and add a project of type class library, name it, IISLogsToWebPerfTestEngine. Delete the default class Program.cs that gets created with the project. 4. Under the IISLogsToWebPerfTestEngine project add a reference to Microsoft.VisualStudio.QualityTools.WebTestFramework – c:\Program Files (x86)\Microsoft Visual Studio 10.0\Common7\IDE\PublicAssemblies\Microsoft.VisualStudio.QualityTools.WebTestFramework.dll LogParser also called MSUtil - c:\users\tarora\documents\visual studio 2010\Projects\IisLogsToWebPerfTest\IisLogsToWebPerfTestEngine\obj\Debug\Interop.MSUtil.dll 5. Right click IISLogsToWebPerfTestEngine project and add a new classes – IISLogReader.cs The IISLogReader class queries the iis logs using the log parser. using System; using System.Collections.Generic; using System.Text; using MSUtil; using LogQuery = MSUtil.LogQueryClassClass; using IISLogInputFormat = MSUtil.COMIISW3CInputContextClassClass; using LogRecordSet = MSUtil.ILogRecordset; using Microsoft.VisualStudio.TestTools.WebTesting; using System.Diagnostics; namespace IisLogsToWebPerfTestEngine { // By making use of log parser it is possible to query the iis log using select queries public class IISLogReader { private string _iisLogPath; public IISLogReader(string iisLogPath) { _iisLogPath = iisLogPath; } public IEnumerable<WebTestRequest> GetRequests() { LogQuery logQuery = new LogQuery(); IISLogInputFormat iisInputFormat = new IISLogInputFormat(); // currently these columns give us suffient information to construct the web test requests string query = @"SELECT s-ip, s-port, cs-method, cs-uri-stem, cs-uri-query FROM " + _iisLogPath; LogRecordSet recordSet = logQuery.Execute(query, iisInputFormat); // Apply a bit of transformation while (!recordSet.atEnd()) { ILogRecord record = recordSet.getRecord(); if (record.getValueEx("cs-method").ToString() == "GET") { string server = record.getValueEx("s-ip").ToString(); string path = record.getValueEx("cs-uri-stem").ToString(); string querystring = record.getValueEx("cs-uri-query").ToString(); StringBuilder urlBuilder = new StringBuilder(); urlBuilder.Append("http://"); urlBuilder.Append(server); urlBuilder.Append(path); if (!String.IsNullOrEmpty(querystring)) { urlBuilder.Append("?"); urlBuilder.Append(querystring); } // You could make substitutions by introducing parameterized web tests. WebTestRequest request = new WebTestRequest(urlBuilder.ToString()); Debug.WriteLine(request.UrlWithQueryString); yield return request; } recordSet.moveNext(); } Console.WriteLine(" That's it! Closing the reader"); recordSet.close(); } } }   6. Connect the dots by adding the project reference ‘IisLogsToWebPerfTestEngine’ to ‘IisLogsToWebPerfTest’. Right click the ‘IisLogsToWebPerfTest’ project and add a new class ‘WebTest1Coded.cs’ The WebTest1Coded.cs inherits from the WebTest class. By overriding the GetRequestMethod we can inject the log files to the IISLogReader class which uses Log parser to query the log file and extract the web requests to generate the web test request which is yielded back for play back when the test is run. namespace IisLogsToWebPerfTest { using System; using System.Collections.Generic; using System.Text; using Microsoft.VisualStudio.TestTools.WebTesting; using Microsoft.VisualStudio.TestTools.WebTesting.Rules; using IisLogsToWebPerfTestEngine; // This class is a coded web performance test implementation, that simply passes // the path of the iis logs to the IisLogReader class which does the heavy // lifting of reading the contents of the log file and converting them to tests. // You could have multiple such classes that inherit from WebTest and implement // GetRequestEnumerator Method and pass differnt log files for different tests. public class WebTest1Coded : WebTest { public WebTest1Coded() { this.PreAuthenticate = true; } public override IEnumerator<WebTestRequest> GetRequestEnumerator() { // substitute the highlighted path with the path of the iis log file IISLogReader reader = new IISLogReader(@"C:\Demo\iisLog1.log"); foreach (WebTestRequest request in reader.GetRequests()) { yield return request; } } } }   7. Its time to fire the test off and see the iis log playback as a web performance test. From the Test menu choose Test View Window you should be able to see the WebTest1Coded test show up. Highlight the test and press Run selection (you can also debug the test in case you face any failures during test execution). 8. Optionally you can create a Load Test by keeping ‘WebTest1Coded’ as the base test. Conclusion You have just helped your testing team, you now have become the coolest developer in your organization! Jokes apart, log parser and web performance test together allow you to save a lot of time by not having to worry about what to test or even worrying about how to record the test. If you haven’t already, download the solution from here. You can take this to the next level by using LogParser to extract the log files as part of an end of day batch to a database. See the usage trends by user this solution over a longer term and have your tests consume the web requests now stored in the database to generate the web performance tests. If you like the post, don’t forget to share … Keep RocKiNg!

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• Online ALTER TABLE in MySQL 5.6

  - by Marko Mäkelä

  This is the low-level view of data dictionary language (DDL) operations in the InnoDB storage engine in MySQL 5.6. John Russell gave a more high-level view in his blog post April 2012 Labs Release – Online DDL Improvements. MySQL before the InnoDB Plugin Traditionally, the MySQL storage engine interface has taken a minimalistic approach to data definition language. The only natively supported operations were CREATE TABLE, DROP TABLE and RENAME TABLE. Consider the following example: CREATE TABLE t(a INT); INSERT INTO t VALUES (1),(2),(3); CREATE INDEX a ON t(a); DROP TABLE t; The CREATE INDEX statement would be executed roughly as follows: CREATE TABLE temp(a INT, INDEX(a)); INSERT INTO temp SELECT * FROM t; RENAME TABLE t TO temp2; RENAME TABLE temp TO t; DROP TABLE temp2; You could imagine that the database could crash when copying all rows from the original table to the new one. For example, it could run out of file space. Then, on restart, InnoDB would roll back the huge INSERT transaction. To fix things a little, a hack was added to ha_innobase::write_row for committing the transaction every 10,000 rows. Still, it was frustrating that even a simple DROP INDEX would make the table unavailable for modifications for a long time. Fast Index Creation in the InnoDB Plugin of MySQL 5.1 MySQL 5.1 introduced a new interface for CREATE INDEX and DROP INDEX. The old table-copying approach can still be forced by SET old_alter_table=0. This interface is used in MySQL 5.5 and in the InnoDB Plugin for MySQL 5.1. Apart from the ability to do a quick DROP INDEX, the main advantage is that InnoDB will execute a merge-sort algorithm before inserting the index records into each index that is being created. This should speed up the insert into the secondary index B-trees and potentially result in a better B-tree fill factor. The 5.1 ALTER TABLE interface was not perfect. For example, DROP FOREIGN KEY still invoked the table copy. Renaming columns could conflict with InnoDB foreign key constraints. Combining ADD KEY and DROP KEY in ALTER TABLE was problematic and not atomic inside the storage engine. The ALTER TABLE interface in MySQL 5.6 The ALTER TABLE storage engine interface was completely rewritten in MySQL 5.6. Instead of introducing a method call for every conceivable operation, MySQL 5.6 introduced a handful of methods, and data structures that keep track of the requested changes. In MySQL 5.6, online ALTER TABLE operation can be requested by specifying LOCK=NONE. Also LOCK=SHARED and LOCK=EXCLUSIVE are available. The old-style table copying can be requested by ALGORITHM=COPY. That one will require at least LOCK=SHARED. From the InnoDB point of view, anything that is possible with LOCK=EXCLUSIVE is also possible with LOCK=SHARED. Most ALGORITHM=INPLACE operations inside InnoDB can be executed online (LOCK=NONE). InnoDB will always require an exclusive table lock in two phases of the operation. The execution phases are tied to a number of methods: handler::check_if_supported_inplace_alter Checks if the storage engine can perform all requested operations, and if so, what kind of locking is needed. handler::prepare_inplace_alter_table InnoDB uses this method to set up the data dictionary cache for upcoming CREATE INDEX operation. We need stubs for the new indexes, so that we can keep track of changes to the table during online index creation. Also, crash recovery would drop any indexes that were incomplete at the time of the crash. handler::inplace_alter_table In InnoDB, this method is used for creating secondary indexes or for rebuilding the table. This is the ‘main’ phase that can be executed online (with concurrent writes to the table). handler::commit_inplace_alter_table This is where the operation is committed or rolled back. Here, InnoDB would drop any indexes, rename any columns, drop or add foreign keys, and finalize a table rebuild or index creation. It would also discard any logs that were set up for online index creation or table rebuild. The prepare and commit phases require an exclusive lock, blocking all access to the table. If MySQL times out while upgrading the table meta-data lock for the commit phase, it will roll back the ALTER TABLE operation. In MySQL 5.6, data definition language operations are still not fully atomic, because the data dictionary is split. Part of it is inside InnoDB data dictionary tables. Part of the information is only available in the *.frm file, which is not covered by any crash recovery log. But, there is a single commit phase inside the storage engine. Online Secondary Index Creation It may occur that an index needs to be created on a new column to speed up queries. But, it may be unacceptable to block modifications on the table while creating the index. It turns out that it is conceptually not so hard to support online index creation. All we need is some more execution phases: Set up a stub for the index, for logging changes. Scan the table for index records. Sort the index records. Bulk load the index records. Apply the logged changes. Replace the stub with the actual index. Threads that modify the table will log the operations to the logs of each index that is being created. Errors, such as log overflow or uniqueness violations, will only be flagged by the ALTER TABLE thread. The log is conceptually similar to the InnoDB change buffer. The bulk load of index records will bypass record locking. We still generate redo log for writing the index pages. It would suffice to log page allocations only, and to flush the index pages from the buffer pool to the file system upon completion. Native ALTER TABLE Starting with MySQL 5.6, InnoDB supports most ALTER TABLE operations natively. The notable exceptions are changes to the column type, ADD FOREIGN KEY except when foreign_key_checks=0, and changes to tables that contain FULLTEXT indexes. The keyword ALGORITHM=INPLACE is somewhat misleading, because certain operations cannot be performed in-place. For example, changing the ROW_FORMAT of a table requires a rebuild. Online operation (LOCK=NONE) is not allowed in the following cases: when adding an AUTO_INCREMENT column, when the table contains FULLTEXT indexes or a hidden FTS_DOC_ID column, or when there are FOREIGN KEY constraints referring to the table, with ON…CASCADE or ON…SET NULL option. The FOREIGN KEY limitations are needed, because MySQL does not acquire meta-data locks on the child or parent tables when executing SQL statements. Theoretically, InnoDB could support operations like ADD COLUMN and DROP COLUMN in-place, by lazily converting the table to a newer format. This would require that the data dictionary keep multiple versions of the table definition. For simplicity, we will copy the entire table, even for DROP COLUMN. The bulk copying of the table will bypass record locking and undo logging. For facilitating online operation, a temporary log will be associated with the clustered index of table. Threads that modify the table will also write the changes to the log. When altering the table, we skip all records that have been marked for deletion. In this way, we can simply discard any undo log records that were not yet purged from the original table. Off-page columns, or BLOBs, are an important consideration. We suspend the purge of delete-marked records if it would free any off-page columns from the old table. This is because the BLOBs can be needed when applying changes from the log. We have special logging for handling the ROLLBACK of an INSERT that inserted new off-page columns. This is because the columns will be freed at rollback.

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• Simplifying Human Capital Management with Mobile Applications

  - by HCM-Oracle

  By Aaron Green If you're starting to think 'mobility' is a recurring theme in your reading, you'd be right. For those who haven't started to build organisational capabilities to leverage it, it's fair to say you're late to the party. The good news: better late than never. Research firm eMarketer says the worldwide smartphone audience will total 1.75 billion this year, while communications technology and services provider Ericsson suggests smartphones will triple to 5.6 billion globally by 2019. It should be no surprise, smart phone adoption is reaching the farthest corners of the globe; the subsequent impact of enterprise applications enabled by these devices is driving business performance improvement and will continue to do so. Companies using advanced workforce analytics can add significantly to the bottom line, while impacting customer satisfaction, quality and productivity. It's a statement that makes most business leaders sit forward in their chairs. Achieving these three standards is like sipping The Golden Elixir for the business world. No-one would argue their importance. So what are 'advanced workforce analytics?' Simply, they're unprecedented access to workforce trends and performance markers. Many are made possible by a mobile world and the enterprise applications that come with it on smart devices. Some refer to it as 'the consumerisation of IT'. As this phenomenon has matured and become more widely appreciated it has impacted the spectrum of functional units within an enterprise differently, but powerfully. Whether it's sales, HR, marketing, IT, or operations, all have benefited from a more mobile approach. It has been the catalyst for improvement in, and management of, the employee experience. The net result of which is happier customers. The obvious benefits but the lesser realised impact Most people understand that mobility allows for greater efficiency and productivity, collaboration and flexibility, but how that translates into business outcomes within the various functional groups is lesser known. In actuality mobility has helped galvanise partnerships between cross-functional groups within the enterprise. Where in some quarters it was once feared mobility could fragment a workforce, its rallying cry of support is coming from what you might describe as an unlikely source - HR. As the bedrock of an enterprise, it is conceivable HR might contemplate the possible negative impact of a mobile workforce that no-longer sits in an office, at the same desks every day. After all, who would know what they were doing or saying? How would they collaborate? It's reasonable to see why HR might have a legitimate claim to try and retain as much 'perceived control' as possible. The reality however is mobility has emancipated human capital and its management. Mobility and enterprise applications are expediting decision making. Google calls it Zero Moment of Truth, or ZMOT. It enables smoother operation and can contribute to faster growth. From a collaborative perspective, with the growing use of enterprise social media, which in many cases is being driven by HR, workforce planning and the tangible impact of change is much easier to map. This in turn provides a platform from which individuals and teams can thrive. With more agility and ability to anticipate, staff satisfaction and retention is higher, and real time feedback constant. The management team can save time, energy and costs with more accurate data, which is then intelligently applied across the workforce to truly engage with staff, customers and partners. From a human capital management (HCM) perspective, mobility can help you close the loop on true talent management. It can enhance what managers can offer and what employees can provide in return. It can create nested relationships and powerful partnerships. IT and HR - partners and stewards of mobility One effect of enterprise mobility is an evolution in the nature of the relationship between HR and IT from one of service provision to partnership. The reason for the dynamic shift is largely due to the 'bring your own device' (BYOD) movement, which is transitioning to a 'bring your own application' (BYOA) scenario. As enterprise technology has in some ways reverse-engineered its solutions to help manage this situation, the partnership between IT (the functional owner) and HR (the strategic enabler) is deeply entrenched. And it has to be. The CIO and the HR leader are faced with compliance and regulatory issues and concerns around information security and personal privacy on a daily basis, complicated by global reach and varied domestic legislation. There are tens of thousands of new mobile apps entering the market each month and, unlike many consumer applications which get downloaded but are often never opened again after initial perusal, enterprise applications are being relied upon by functional groups, not least by HR to enhance people management. It requires a systematic approach across all applications in use within the enterprise in order to ensure they're used to best effect. No turning back, and no desire to With real time analytics on performance and the ability for immediate feedback, there is no turning back for managers. In my experience with Oracle, our customers' operational efficiency is at record levels. It's clear as a result of the combination of individual KPIs and organisational goals, CIOs have been able to give HR leaders the ability to build predictive models that feed into an enterprise organisations' evolving strategy. It also helps them ensure regulatory compliance much more easily. Once an arduous task, with mobile enabled automation and quality data, compliance is simpler. Their world has changed for the better. For the CIO, mobility also assists them to optimise performance. While it doesn't come without challenges, mobile-enabled applications and the native experience users have with them means employees don't need high-level technical expertise to train users. It reduces the training and engagement required from the IT team so they can focus on other things that deliver value to the bottom line; all the while lowering the cost of assets and related maintenance work by simplifying processes. Rewards of a mobile enterprise outweigh risks With mobile tools allowing us to increasingly integrate our personal and professional lives, terms like "office hours" are becoming irrelevant, so work/life balance is a cultural must. Enterprises are expected to offer tools that enable workers to access information from anywhere, at any time, from any device. Employees want simplicity and convenience but it doesn't stop at private enterprise. This is a societal shift. Governments, which traditionally have been known to be slower to adopt newer technology, are also offering support for local businesses to go mobile. Several state government websites have advice on how to create mobile apps and more. And as recently as last week the Victorian Minister for Technology Gordon Rich-Phillips unveiled his State government's ICT roadmap for the next two years, which details an increased use of the public cloud, as well as mobile communications, and improved access to online data-sets. Tech giants are investing significantly in solutions designed to simplify mobile deployment and enablement. The mobility trend is creating a wave of change in the industry and driving transformation in the enterprise. If you're not on that wave, the business risk continues to rise as your competitiveness drops. Aaron is the Vice President of HCM Strategy at Oracle Corporation where he is responsible for researching and identifying emerging trends in the practice of Human Resources and works to deliver industry-leading technology solutions. Other responsibilities include, ownership of Oracle's innovative HCM solutions across JAPAC and enabling organisations to transform and modernise their workforce tools. Follow him on Twitter @aaronjgreen

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• Benefits of Behavior Driven Development

  - by Aligned

  Originally posted on: http://geekswithblogs.net/Aligned/archive/2013/07/26/benefits-of-behavior-driven-development.aspxContinuing my previous article on BDD, I wanted to point out some benefits of BDD and since BDD is an extension of Test Driven Development (TDD), you get those as well. I’ll add another article on some possible downsides of this approach. There are many articles about the benefits of TDD and they apply to BDD. I’ve pointed out some here and copied some of the main points for each article, but there are many more including the book The Art of Unit Testing by Roy Osherove. http://geekswithblogs.net/leesblog/archive/2008/04/30/the-benefits-of-test-driven-development.aspx (Lee Brandt) Stability Accountability Design Ability Separated Concerns Progress Indicator http://tddftw.com/benefits-of-tdd/ Help maintainers understand the intention behind the code Bring validation and proper data handling concerns to the forefront. Writing the tests first is fun. Better APIs come from writing testable code. TDD will make you a better developer. http://www.slideshare.net/dhelper/benefit-from-unit-testing-in-the-real-world (from Typemock). Take a look at the slides, especially the extra time required for TDD (slide 10) and the next one of the bugs avoided using TDD (slide 11). Less bugs (slide 11) about testing and development (13) Increase confidence in code (14) Fearlessly change your code (14) Document Requirements (14) also see http://visualstudiomagazine.com/articles/2013/06/01/roc-rocks.aspx Discover usability issues early (14) All these points and articles are great and there are many more. The following are my additions to the benefits of BDD from using it in real projects for my company. July 2013 on MSDN - Behavior-Driven Design with SpecFlow Scott Allen did a very informative TDD and MVC module, but to me he is doing BDDCompile and Execute Requirements in Microsoft .NET ~ Video from TechEd 2012 Communication I was working through a complicated task that the decision tree kept growing. After writing out the Given, When, Then of the scenario, I was able tell QA what I had worked through for their initial test cases. They were able to add from there. It is also useful to use this language with other developers, managers, or clients to help make informed decisions on if it meets the requirements or if it can simplified to save time (money). Thinking through solutions, before starting to code This was the biggest benefit to me. I like to jump into coding to figure out the problem. Many times I don't understand my path well enough and have to do some parts over. A past supervisor told me several times during reviews that I need to get better at seeing "the forest for the trees". When I sit down and write out the behavior that I need to implement, I force myself to think things out further and catch scenarios before they get to QA. A co-worker that is new to BDD and we’ve been using it in our new project for the last 6 months, said “It really clarifies things”. It took him awhile to understand it all, but now he’s seeing the value of this approach (yes there are some downsides, but that is a different issue). Developers’ Confidence This is huge for me. With tests in place, my confidence grows that I won’t break code that I’m not directly changing. In the past, I’ve worked on projects with out tests and we would frequently find regression bugs (or worse the users would find them). That isn’t fun. We don’t catch all problems with the tests, but when QA catches one, I can write a test to make sure it doesn’t happen again. It’s also good for Releasing code, telling your manager that it’s good to go. As time goes on and the code gets older, how confident are you that checking in code won’t break something somewhere else? Merging code - pre release confidence If you’re merging code a lot, it’s nice to have the tests to help ensure you didn’t merge incorrectly. Interrupted work I had a task that I started and planned out, then was interrupted for a month because of different priorities. When I started it up again, and un-shelved my changes, I had the BDD specs and it helped me remember what I had figured out and what was left to do. It would have much more difficult without the specs and tests. Testing and verifying complicated scenarios Sometimes in the UI there are scenarios that get tricky, because there are a lot of steps involved (click here to open the dialog, enter the information, make sure it’s valid, when I click cancel it should do {x}, when I click ok it should close and do {y}, then do this, etc….). With BDD I can avoid some of the mouse clicking define the scenarios and have them re-run quickly, without using a mouse. UI testing is still needed, but this helps a bunch. The same can be true for tricky server logic. Documentation of Assumptions and Specifications The BDD spec tests (Jasmine or SpecFlow or other tool) also work as documentation and show what the original developer was trying to accomplish. It’s not a different Word document, so developers will keep this up to date, instead of letting it become obsolete. What happens if you leave the project (consulting, new job, etc) with no specs or at the least good comments in the code? Sometimes I think of a new scenario, so I add a failing spec and continue in the same stream of thought (don’t forget it because it was on a piece of paper or in a notepad). Then later I can come back and handle it and have it documented. Jasmine tests and JavaScript –> help deal with the non-typed system I like JavaScript, but I also dislike working with JavaScript. I miss C# telling me if a property doesn’t actually exist at build time. I like the idea of TypeScript and hope to use it more in the future. I also use KnockoutJs, which has observables that need to be called with ending (), since the observable is a function. It’s hard to remember when to use () or not and the Jasmine specs/tests help ensure the correct usage.   This should give you an idea of the benefits that I see in using the BDD approach. I’m sure there are more. It talks a lot of practice, investment and experimentation to figure out how to approach this and to get comfortable with it. I agree with Scott Allen in the video I linked above “Remember that TDD can take some practice. So if you're not doing test-driven design right now? You can start and practice and get better. And you'll reach a point where you'll never want to get back.”

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• PASS Summit 2010 BI Workshop Feedbacks

  - by Davide Mauri

  As many other speakers already did, I’d like to share with the SQL Community the feedback of my PASS Summit 2010 Workshop. For those who were not there, my workshop was the “BI From A-Z” and the main objective of that workshop was to introduce people in the BI world not only from a technical point of view but insist a lot on the methodological and “engineered” approach. The will to put more engineering in the IT (and specially in the BI field) is something that has been growing stronger and stronger in me every day for of this last 5 years since is simply envy the fact that Airbus, Fincatieri, BMW (just to name a few) can create very complex machine “just” using putting people together and giving them some rules to follow (Of course this is an oversimplification but I think you get what I mean). The key point of engineering is that, after having defined the project blueprint, you have the possibility to give to a huge number of people, the rules to follow, the correct tools in order to implement the rules easily and semi-automatically and a way to measure the quality of the results. Could this be done in IT? Very big question, so my scope is now limited to BI. So that’s the main point of my workshop: and entry-level approach to BI (level was 200) in order to allow attendees to know the basics, to understand what tools they should use for which purpose and, above all, a set of rules and tools in order to make a BI solution scalable in terms of people working on it, while still maintaining a very good quality. All done not focusing only on the practice but explaining the theory behind to see how it can help *a lot* to build a correct solution despite the technology used to implement it. The idea is to reach a point where more then 70% of the work done to create a BI solution can be reused even if technologies changes. This is a very demanding challenge nowadays with the coming of Denali and its column-aligned storage and the shiny-new DAX language. As you may understand I was looking forward to get the feedback since you may have noticed that there’s a lot of “architectural” stuff in IT but really nothing on “engineering”. So how the session could be perceived by the attendees was really unknown to me. The feedback could also give a good indication if the need of more “engineering” is something I feel only by myself or if is something more broad. I’m very happy to be able to say that the overall score of 4.75 put my workshop in the TOP 20 session (on near 200 sessions)! Here’s the detailed evaluations: How would you rate the usefulness of the information presented in your day-to-day environment? 4.75 Answer:    # of Responses 3    1         4    12        5    42               How would you rate the Speaker's presentation skills? 4.80 Answer:    # of Responses 3 : 1         4 : 9         5 : 45               How would you rate the Speaker's knowledge of the subject? 4.95 Answer:    # of Responses 4 :  3         5 : 52               How would you rate the accuracy of the session title, description and experience level to the actual session? 4.75 Answer:    # of Responses 3 : 2         4 : 10         5 : 43               How would you rate the amount of time allocated to cover the topic/session? 4.44 Answer:    # of Responses 3 : 7         4 : 17        5 : 31               How would you rate the quality of the presentation materials? 4.62 Answer:    # of Responses 4 : 21        5 : 34 The comments where all very positive. Many of them asked for more time on the subject (or to shorten the very last topics). I’ll make treasure of these comments and will review the content accordingly. We’ll organize a two-day classes on this topic, where also more examples will be shown and some arguments will be explained more deeply. I’d just like to answer a comment that asks how much of what I shown is “universally applicable”. I can tell you that all of our BI project follow these rules and they’ve been applied to different markets (Insurance, Fashion, GDO) with different people and different teams and they allowed us to be “Adaptive” against the customer. The more the rules are well defined and the more there are tools that supports their implementations, the easier is to add new people to the project and to add or change solution features. Think of a car. How come that almost any mechanic can help you to fix a problem? Because they know what to expect. Because there a rules that allow them to identify the problem without having to discover each time how the car has been implemented build. And this is of course also true for car upgrades/improvements. Last but not least: thanks a lot to everyone for coming!

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• Delight and Excite

  - by Applications User Experience

  Mick McGee, CEO & President, EchoUser Editor’s Note: EchoUser is a User Experience design firm in San Francisco and a member of the Oracle Usability Advisory Board. Mick and his staff regularly consult on Oracle Applications UX projects. Being part of a user experience design firm, we have the luxury of working with a lot of great people across many great companies. We get to help people solve their problems.  At least we used to. The basic design challenge is still the same; however, the goal is not necessarily to solve “problems” anymore; it is, “I want our products to delight and excite!” The question for us as UX professionals is how to design to those goals, and then how to assess them from a usability perspective. I’m not sure where I first heard “delight and excite” (A book? blog post? Facebook  status? Steve Jobs quote?), but now I hear these listed as user experience goals all the time. In particular, somewhat paradoxically, I routinely hear them in enterprise software conversations. And when asking these same enterprise companies what will make the project successful, we very often hear, “Make it like Apple.” In past days, it was “make it like Yahoo (or Amazon or Google“) but now Apple is the common benchmark. Steve Jobs and Apple were not secrets, but with Jobs’ passing and Apple becoming the world’s most valuable company in the last year, the impact of great design and experience is suddenly very widespread. In particular, users’ expectations have gone way up. Being an enterprise company is no shield to the general expectations that users now have, for all products. Designing a “Minimum Viable Product” The user experience challenge has historically been, to echo the words of Eric Ries (author of Lean Startup) , to create a “minimum viable product”: the proverbial, “make it good enough”. But, in our profession, the “minimum viable” part of that phrase has oftentimes, unfortunately, referred to the design and user experience. Technology typically dominated the focus of the biggest, most successful companies. Few have had the laser focus of Apple to also create and sell design and user experience alongside great technology. But now that Apple is the most valuable company in the world, copying their success is a common undertaking. Great design is now a premium offering that everyone wants, from the one-person startup to the largest companies, consumer and enterprise. This emerging business paradigm will have significant impact across the user experience design process and profession. One area that particularly interests me is, how are we going to evaluate these new emerging “delight and excite” experiences, which are further customized to each particular domain? How to Measure “Delight and Excite” Traditional usability measures of task completion rate, assists, time, and errors are still extremely useful in many situations; however, they are too blunt to offer much insight into emerging experiences “Satisfaction” is usually assessed in user testing, in roughly equivalent importance to the above objective metrics. Various surveys and scales have provided ways to measure satisfying UX, with whatever questions they include. However, to meet the demands of new business goals and keep users at the center of design and development processes, we have to explore new methods to better capture custom-experience goals and emotion-driven user responses. We have had success assessing custom experiences, including “delight and excite”, by employing a variety of user testing methods that tend to combine formative and summative techniques (formative being focused more on identifying usability issues and ways to improve design, and summative focused more on metrics). Our most successful tool has been one we’ve been using for a long time, Magnitude Estimation Technique (MET). But it’s not necessarily about MET as a measure, rather how it is created. Caption: For one client, EchoUser did two rounds of testing.  Each test was a mix of performing representative tasks and gathering qualitative impressions. Each user participated in an in-person moderated 1-on-1 session for 1 hour, using a testing set-up where they held the phone. The primary goal was to identify usability issues and recommend design improvements. MET is based on a definition of the desired experience, which users will then use to rate items of interest (usually tasks in a usability test). In other words, a custom experience definition needs to be created. This can then be used to measure satisfaction in accomplishing tasks; “delight and excite”; or anything else from strategic goals, user demands, or elsewhere. For reference, our standard MET definition in usability testing is: “User experience is your perception of how easy to use, well designed and productive an interface is to complete tasks.” Articulating the User Experience We’ve helped construct experience definitions for several clients to better match their business goals. One example is a modification of the above that was needed for a company that makes medical-related products: “User experience is your perception of how easy to use, well-designed, productive and safe an interface is for conducting tasks. ‘Safe’ is how free an environment (including devices, software, facilities, people, etc.) is from danger, risk, and injury.” Another example is from a company that is pushing hard to incorporate “delight” into their enterprise business line: “User experience is your perception of a product’s ease of use and learning, satisfaction and delight in design, and ability to accomplish objectives.” I find the last one particularly compelling in that there is little that identifies the experience as being for a highly technical enterprise application. That definition could easily be applied to any number of consumer products. We have gone further than the above, including “sexy” and “cool” where decision-makers insisted they were part of the desired experience. We also applied it to completely different experiences where the “interface” was, for example, riding public transit, the “tasks” were train rides, and we followed the participants through the train-riding journey and rated various aspects accordingly: “A good public transportation experience is a cost-effective way of reliably, conveniently, and safely getting me to my intended destination on time.” To construct these definitions, we’ve employed both bottom-up and top-down approaches, depending on circumstances. For bottom-up, user inputs help dictate the terms that best fit the desired experience (usually by way of cluster and factor analysis). Top-down depends on strategic, visionary goals expressed by upper management that we then attempt to integrate into product development (e.g., “delight and excite”). We like a combination of both approaches to push the innovation envelope, but still be mindful of current user concerns. Hopefully the idea of crafting your own custom experience, and a way to measure it, can provide you with some ideas how you can adapt your user experience needs to whatever company you are in. Whether product-development or service-oriented, nearly every company is ultimately providing a user experience. The Bottom Line Creating great experiences may have been popularized by Steve Jobs and Apple, but I’ll be honest, it’s a good feeling to be moving from “good enough” to “delight and excite,” despite the challenge that entails. In fact, it’s because of that challenge that we will expand what we do as UX professionals to help deliver and assess those experiences. I’m excited to see how we, Oracle, and the rest of the industry will live up to that challenge.

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• Notes on implementing Visual Studio 2010 Navigate To

  - by cyberycon

  One of the many neat functions added to Visual Studio in VS 2010 was the Navigate To feature. You can find it by clicking Edit, Navigate To, or by using the keyboard shortcut Ctrl, (yes, that's control plus the comma key). This pops up the Navigate To dialog that looks like this: As you type, Navigate To starts searching through a number of different search providers for your term. The entries in the list change as you type, with most providers doing some kind of fuzzy or at least substring matching. If you have C#, C++ or Visual Basic projects in your solution, all symbols defined in those projects are searched. There's also a file search provider, which displays all matching filenames from projects in the current solution as well. And, if you have a Visual Studio package of your own, you can implement a provider too. Micro Focus (where I work) provide the Visual COBOL language inside Visual Studio (http://visualstudiogallery.msdn.microsoft.com/ef9bc810-c133-4581-9429-b01420a9ea40 ), and we wanted to provide this functionality too. This post provides some notes on the things I discovered mainly through trial and error, but also with some kind help from devs inside Microsoft. The expectation of Navigate To is that it searches across the whole solution, not just the current project. So in our case, we wanted to search for all COBOL symbols inside all of our Visual COBOL projects inside the solution. So first of all, here's the Microsoft documentation on Navigate To: http://msdn.microsoft.com/en-us/library/ee844862.aspx . It's the reference information on the Microsoft.VisualStudio.Language.NavigateTo.Interfaces Namespace, and it lists all the interfaces you will need to implement to create your own Navigate To provider. Navigate To uses Visual Studio's latest mechanism for integrating external functionality and services, Managed Extensibility Framework (MEF). MEF components don't require any registration with COM or any other registry entries to be found by Visual Studio. Visual Studio looks in several well-known locations for manifest files (extension.vsixmanifest). It then uses reflection to scan for MEF attributes on classes in the assembly to determine which functionality the assembly provides. MEF itself is actually part of the .NET framework, and you can learn more about it here: http://mef.codeplex.com/. To get started with Visual Studio and MEF you could do worse than look at some of the editor examples on the VSX page http://archive.msdn.microsoft.com/vsx . I've also written a small application to help with switching between development and production MEF assemblies, which you can find on Codeproject: http://www.codeproject.com/KB/miscctrl/MEF_Switch.aspx. The Navigate To interfaces Back to Navigate To, and summarizing the MSDN reference documentation, you need to implement the following interfaces: INavigateToItemProviderFactoryThis is Visual Studio's entry point to your Navigate To implementation, and you must decorate your implementation with the following MEF export attribute: [Export(typeof(INavigateToItemProviderFactory))]  INavigateToItemProvider Your INavigateToItemProviderFactory needs to return your implementation of INavigateToItemProvider. This class implements StartSearch() and StopSearch(). StartSearch() is the guts of your provider, and we'll come back to it in a minute. This object also needs to implement IDisposeable(). INavigateToItemDisplayFactory Your INavigateToItemProvider hands back NavigateToItems to the NavigateTo framework. But to give you good control over what appears in the NavigateTo dialog box, these items will be handed back to your INavigateToItemDisplayFactory, which must create objects implementing INavigateToItemDisplay  INavigateToItemDisplay Each of these objects represents one result in the Navigate To dialog box. As well as providing the description and name of the item, this object also has a NavigateTo() method that should be capable of displaying the item in an editor when invoked. Carrying out the search The lifecycle of your INavigateToItemProvider is the same as that of the Navigate To dialog. This dialog is modal, which makes your implementation a little easier because you know that the user can't be changing things in editors and the IDE while this dialog is up. But the Navigate To dialog DOES NOT run on the main UI thread of the IDE – so you need to be aware of that if you want to interact with editors or other parts of the IDE UI. When the user invokes the Navigate To dialog, your INavigateToItemProvider gets sent a TryCreateNavigateToItemProvider() message. Instantiate your INavigateToItemProvider and hand this back. The sequence diagram below shows what happens next. Your INavigateToItemProvider will get called with StartSearch(), and passed an INavigateToCallback. StartSearch() is an asynchronous request – you must return from this method as soon as possible, and conduct your search on a separate thread. For each match to the search term, instantiate a NavigateToItem object and send it to INavigateToCallback.AddItem(). But as the user types in the Search Terms field, NavigateTo will invoke your StartSearch() method repeatedly with the changing search term. When you receive the next StartSearch() message, you have to abandon your current search, and start a new one. You can't rely on receiving a StopSearch() message every time. Finally, when the Navigate To dialog box is closed by the user, you will get a Dispose() message – that's your cue to abandon any uncompleted searches, and dispose any resources you might be using as part of your search. While you conduct your search invoke INavigateToCallback.ReportProgress() occasionally to provide feedback about how close you are to completing the search. There does not appear to be any particular requirement to how often you invoke ReportProgress(), and you report your progress as the ratio of two integers. In my implementation I report progress in terms of the number of symbols I've searched over the total number of symbols in my dictionary, and send a progress report every 16 symbols. Displaying the Results The Navigate to framework invokes INavigateToItemDisplayProvider.CreateItemDisplay() once for each result you passed to the INavigateToCallback. CreateItemDisplay() is passed the NavigateToItem you handed to the callback, and must return an INavigateToItemDisplay object. NavigateToItem is a sealed class which has a few properties, including the name of the symbol. It also has a Tag property, of type object. This enables you to stash away all the information you will need to create your INavigateToItemDisplay, which must implement an INavigateTo() method to display a symbol in an editor IDE when the user double-clicks an entry in the Navigate To dialog box. Since the tag is of type object, it is up to you, the implementor, to decide what kind of object you store in here, and how it enables the retrieval of other information which is not included in the NavigateToItem properties. Some of the INavigateToItemDisplay properties are self-explanatory, but a couple of them are less obvious: Additional informationThe string you return here is displayed inside brackets on the same line as the Name property. In English locales, Visual Studio includes the preposition "of". If you look at the first line in the Navigate To screenshot at the top of this article, Book_WebRole.Default is the additional information for textBookAuthor, and is the namespace qualified type name the symbol appears in. For procedural COBOL code we display the Program Id as the additional information DescriptionItemsYou can use this property to return any textual description you want about the item currently selected. You return a collection of DescriptionItem objects, each of which has a category and description collection of DescriptionRun objects. A DescriptionRun enables you to specify some text, and optional formatting, so you have some control over the appearance of the displayed text. The DescriptionItems property is displayed at the bottom of the Navigate To dialog box, with the Categories on the left and the Descriptions on the right. The Visual COBOL implementation uses it to display more information about the location of an item, making it easier for the user to know disambiguate duplicate names (something there can be a lot of in large COBOL applications). Summary I hope this article is useful for anyone implementing Navigate To. It is a fantastic navigation feature that Microsoft have added to Visual Studio, but at the moment there still don't seem to be any examples on how to implement it, and the reference information on MSDN is a little brief for anyone attempting an implementation.

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• Box2D blocky map. Body, Fixtures a huge map and performance

  - by Solom

  Right now I'm still in the planning phase of a my very first game. I'm creating a "Minecraft"-like game in 2D that features blocks that can be destroyed as well as players moving around the map. For creating the map I chose a 2D-Array of Integers that represent the Block ID. For testing purposes I created a huge map (16348 * 256) and in my prototype that didn't use Box2D everything worked like a charm. I only rendered those blocks that where within the bounds of my camera and got 60 fps straight. The problem started when I decided to use an existing physics-solution rather than implementing my own one. What I had was basically simple hitboxes around the blocks and then I had to manually check if the player collided with any of those in his neighborhood. For more advanced physics as well as the collision detection I want to switch over to Box2D. The problem I have right now is ... how to go about the bodies? I mean, the blocks are of a static bodytype. They don't move on their own, they just are there to be collided with. But as far as I can see it, every block needs his own body with a rectangular fixture attached to it, so as to be destroyable. But for a huge map such as mine, this turns out to be a real performance bottle-neck. (In fact even a rather small map [compared to the other] of 1024*256 is unplayable.) I mean I create thousands of thousands of blocks. Even if I just render those that are in my immediate neighborhood there are hundreds of them and (at least with the debugRenderer) I drop to 1 fps really quickly (on my own "monster machine"). I thought about strategies like creating just one body, attaching multiple fixtures and only if a fixture got hit, separate it from the body, create a new one and destroy it, but this didn't turn out quite as successful as hoped. (In fact the core just dumps. Ah hello C! I really missed you :X) Here is the code: public class Box2DGameScreen implements Screen { private World world; private Box2DDebugRenderer debugRenderer; private OrthographicCamera camera; private final float TIMESTEP = 1 / 60f; // 1/60 of a second -> 1 frame per second private final int VELOCITYITERATIONS = 8; private final int POSITIONITERATIONS = 3; private Map map; private BodyDef blockBodyDef; private FixtureDef blockFixtureDef; private BodyDef groundDef; private Body ground; private PolygonShape rectangleShape; @Override public void show() { world = new World(new Vector2(0, -9.81f), true); debugRenderer = new Box2DDebugRenderer(); camera = new OrthographicCamera(); // Pixel:Meter = 16:1 // Body definition BodyDef ballDef = new BodyDef(); ballDef.type = BodyDef.BodyType.DynamicBody; ballDef.position.set(0, 1); // Fixture definition FixtureDef ballFixtureDef = new FixtureDef(); ballFixtureDef.shape = new CircleShape(); ballFixtureDef.shape.setRadius(.5f); // 0,5 meter ballFixtureDef.restitution = 0.75f; // between 0 (not jumping up at all) and 1 (jumping up the same amount as it fell down) ballFixtureDef.density = 2.5f; // kg / m² ballFixtureDef.friction = 0.25f; // between 0 (sliding like ice) and 1 (not sliding) // world.createBody(ballDef).createFixture(ballFixtureDef); groundDef = new BodyDef(); groundDef.type = BodyDef.BodyType.StaticBody; groundDef.position.set(0, 0); ground = world.createBody(groundDef); this.map = new Map(20, 20); rectangleShape = new PolygonShape(); // rectangleShape.setAsBox(1, 1); blockFixtureDef = new FixtureDef(); // blockFixtureDef.shape = rectangleShape; blockFixtureDef.restitution = 0.1f; blockFixtureDef.density = 10f; blockFixtureDef.friction = 0.9f; } @Override public void render(float delta) { Gdx.gl.glClearColor(1, 1, 1, 1); Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT); debugRenderer.render(world, camera.combined); drawMap(); world.step(TIMESTEP, VELOCITYITERATIONS, POSITIONITERATIONS); } private void drawMap() { for(int a = 0; a < map.getHeight(); a++) { /* if(camera.position.y - (camera.viewportHeight/2) > a) continue; if(camera.position.y - (camera.viewportHeight/2) < a) break; */ for(int b = 0; b < map.getWidth(); b++) { /* if(camera.position.x - (camera.viewportWidth/2) > b) continue; if(camera.position.x - (camera.viewportWidth/2) < b) break; */ /* blockBodyDef = new BodyDef(); blockBodyDef.type = BodyDef.BodyType.StaticBody; blockBodyDef.position.set(b, a); world.createBody(blockBodyDef).createFixture(blockFixtureDef); */ PolygonShape rectangleShape = new PolygonShape(); rectangleShape.setAsBox(1, 1, new Vector2(b, a), 0); blockFixtureDef.shape = rectangleShape; ground.createFixture(blockFixtureDef); rectangleShape.dispose(); } } } @Override public void resize(int width, int height) { camera.viewportWidth = width / 16; camera.viewportHeight = height / 16; camera.update(); } @Override public void hide() { dispose(); } @Override public void pause() { } @Override public void resume() { } @Override public void dispose() { world.dispose(); debugRenderer.dispose(); } } As you can see I'm facing multiple problems here. I'm not quite sure how to check for the bounds but also if the map is bigger than 24*24 like 1024*256 Java just crashes -.-. And with 24*24 I get like 9 fps. So I'm doing something really terrible here, it seems and I assume that there most be a (much more performant) way, even with Box2D's awesome physics. Any other ideas? Thanks in advance!

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• Different Not Automatically Implies Better

  - by Alois Kraus

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

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• SOA Implementation Challenges

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

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