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  • Start a thread using a method pointer

    - by Michael
    Hi ! I'm trying to develop a thread abstraction (POSIX thread and thread from the Windows API), and I would very much like it to be able to start them with a method pointer, and not a function pointer. What I would like to do is an abstraction of thread being a class with a pure virtual method "runThread", which would be implanted in the future threaded class. I don't know yet about the Windows thread, but to start a POSIX thread, you need a function pointer, and not a method pointer. And I can't manage to find a way to associate a method with an instance so it could work as a function. I probably just can't find the keywords (and I've been searching a lot), I think it's pretty much what Boost::Bind() does, so it must exist. Can you help me ?

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  • algorithms that destruct and copy_construct

    - by FredOverflow
    I am currently building my own toy vector for fun, and I was wondering if there is something like the following in the current or next standard or in Boost? template<class T> void destruct(T* begin, T* end) { while (begin != end) { begin -> ~T(); ++begin; } } template<class T> T* copy_construct(T* begin, T* end, T* dst) { while (begin != end) { new(dst) T(*begin); ++begin; ++dst; } return dst; }

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  • toupper/tolower + locale (german)

    - by Oops
    Hi, how to convert a string (wstring) from lowercase to uppercase characters and vice versa? I searched the net and found there is a STL-function std::transform. But until now I hav'nt figured out how to give the right locale-object for example "Germany_german" to the function. Who can help please? my code looks like: wstring strin = L"ABCÄÖÜabcäöü"; wstring str = strin; locale loc( "Germany_german" ); // ??? how to apply this ??? std::transform( str.begin(), str.end(), str.begin(), (int(*)(int)tolower ); //result: "abcäöüabcäöü" The characters ÄÖÜ and äöü (it's like Ae, Oe, Ue) will not be converted correctly. P.S.: I don't prefer a big switch sweat and also I know BOOST is capable of everything, i would prefer a STL solution. thanks in advance Oops

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  • How to pass a function to a function?

    - by ShaChris23
    Suppose I have a class with 2 static functions: class CommandHandler { public: static void command_one(Item); static void command_two(Item); }; I have a problem DRY problem where I have 2 functions that have the exact same code for every single line, except for the function that it calls: void CommandOne_User() { // some code A CommandHandler::command_one(item); // some code B } void CommandTwo_User() { // some code A CommandHandler::command_two(item); // some code B } I would like to remove duplication, and, ideally, do something like this: void CommandOne_User() { Function func = CommandHandler::command_one(); Refactored_CommandUser(func); } void CommandTwo_User() { Function func = CommandHandler::command_one(); Refactored_CommandUser(func); } void Refactored_CommandUser(Function func) { // some code A func(item); } I have access to Qt, but not Boost. Could someone help suggest a way on how I can refactor something like this?

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  • How do you extend python with C++?

    - by superjoe30
    I've successfully extended python with C, thanks to this handy skeleton module. But I can't find one for C++, and I have circular dependency trouble when trying to fix the errors that C++ gives when I compile this skeleton module. How do you extend Python with C++? I'd rather not depend on Boost (or SWIP or other libraries) if I don't have to. Dependencies are a pain in the butt. Best case scenario, I find a skeleton file that already compiles with C++.

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  • How would one call std::forward on all arguments in a variadic function?

    - by Noah Roberts
    I was just writing a generic object factory and using the boost preprocessor meta-library to make a variadic template (using 2010 and it doesn't support them). My function uses rval references and std::forward to do perfect forwarding and it got me thinking...when C++0X comes out and I had a standard compiler I would do this with real variadic templates. How though, would I call std::forward on the arguments? template < typename ... Params void f(Params ... params) // how do I say these are rvalue reference? { y(std::forward(...params)); //? - I doubt this would work. } Only way I can think of would require manual unpacking of ...params and I'm not quite there yet either. Is there a quicker syntax that would work?

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  • Sharing memory between modules

    - by John Holecek
    Hi, I was wondering how to share some memory between different program modules - lets say, I have a main application (exe), and then some module (dll). They both link to the same static library. This static library will have some manager, that provides various services. What I would like to achieve, is to have this manager shared between all application modules, and to do this transparently during the library initialization. Between processes I could use shared memory, but I want this to be shared in the current process only. Could you think of some cross-platform way to do this? Possibly using boost libraries, if they provide some facilities to do this. Only solution I can think of right now, is to use shared library of the respective OS, that all other modules will link to at runtime, and have the manager saved there.

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  • Pass C++ object to Lua function

    - by peterdemin
    Hello there. I have a C++ project, where 1 method of a 1 class changes very often. So I want to take that code from C++ to Lua. Note, I'm novice to Lua. The whole task: Bind some class methods to Lua state machine; Pass reference to class object to a function, written in Lua; Operate with passed C++ object in Lua function. I've found how to make first step with Lunar, and can't cope with second and third. I can't use SWIG and boost.

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  • How do I pick the most beneficial combination of items from a set of items?

    - by Chu
    I'm designing a piece of a game where the AI needs to determine which combination of armor will give the best overall stat bonus to the character. Each character will have about 10 stats, of which only 3-4 are important, and of those important ones, a few will be more important than the others. Armor will also give a boost to 1 or all stats. For example, a shirt might give +4 to the character's int and +2 stamina while at the same time, a pair of pants may have +7 strength and nothing else. So let's say that a character has a healthy choice of armor to use (5 pairs of pants, 5 pairs of gloves, etc.) We've designated that Int and Perception are the most important stats for this character. How could I write an algorithm that would determine which combination of armor and items would result in the highest of any given stat (say in this example Int and Perception)?

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  • Performance of Serialized Objects in C++

    - by jm1234567890
    Hi Everyone, I'm wondering if there is a fast way to dump an STL set to disk and then read it back later. The internal structure of a set is a binary tree, so if I serialize it naively, when I read it back the program will have to go though the process of inserting each element again. I think this is slow even if it is read back in correct order, correct me if I am wrong. Is there a way to "dump" the memory containing the set into disk and then read it back later? That is, keep everything in binary format, thus avoiding the re-insertion. Do the boost serialization tools do this? Thanks! EDIT: oh I should probably read, http://www.parashift.com/c++-faq-lite/serialization.html I will read it now... no it doesn't really help

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  • Segfaults with singletons

    - by Ockonal
    Hello, I have such code: // Non singleton class MyLogManager { void write(message) {Ogre::LogManager::getSingletonPtr()->logMessage(message);} } class Utils : public singleton<Utils> { MyLogManager *handle; MyLogManager& getHandle { return *handle; } }; namespace someNamespace { MyLogManager &Log() { return Utils::get_mutable_instance().getHandle(); } } int main() { someNamespace::Log().write("Starting game initializating..."); } In this code I'm using boost's singleton (from serialization) and calling Ogre's log manager (it's singleton-type too). The program fails at any trying to do something with Ogre::LogManager::getSingletonPtr() object with code User program stopped by signal (SIGSEGV) I checked that getSingletonPtr() returns address 0x000 But using code Utils::get_mutable_instance().getHandle().write("foo") works good in another part of program. What's wrong could be there with calling singletons?

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  • Make object by it's name

    - by Ockonal
    Hello, is it possible to return exemplar of object using passed type name (string) in c++? I have some base abstract class Base and a few derivates. Example code: class Base { /* ... */ }; class Der1 : public Base { /* ... */ }; class Der2 : public Base { /* ... */ }; And I need function like: Base *objectByType(const std::string &name); Number of derivates classes are changeable and I don't want to make something like switching of name and returning by hands new object type. Is it possible in c++ to do that automatically anyway? p.s. usage should looks like: dynamic_cast<Der1>(objectByType("Der1")); I need pure c++ code (crossplatform). Using boost is permissible.

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  • Is PThread a good choice for multi-platorm C/C++ multi-threading program?

    - by RogerV
    Been doing mostly Java and smattering of .NET for last five years and haven't written any significant C or C++ during that time. So have been away from that scene for a while. If I want to write a C or C++ program today that does some multi-threading and is source code portable across Windows, Mac OS X, and Linux/Unix - is PThread a good choice? The C or C++ code won't be doing any GUI, so won't need to worry with any of that. For the Windows platform, I don't want to bring a lot of Unix baggage, though, in terms of unix emulation runtime libraries. Would prefer a PThread API for Windows that is a thin-as-possible wrapper over existing Windows threading APIs. ADDENDUM EDIT: Am leaning toward going with boost:thread - I also want to be able to use C++ try/catch exception handling too. And even though my program will be rather minimal and not particularly OOPish, I like to encapsulate using class and namespace - as opposed to C disembodied functions.

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  • [C++] Start a thread using a method pointer

    - by Michael
    Hi ! I'm trying to develop a thread abstraction (POSIX thread and thread from the Windows API), and I would very much like it to be able to start them with a method pointer, and not a function pointer. What I would like to do is an abstraction of thread being a class with a pure virtual method "runThread", which would be implanted in the future threaded class. I don't know yet about the Windows thread, but to start a POSIX thread, you need a function pointer, and not a method pointer. And I can't manage to find a way to associate a method with an instance so it could work as a function. I probably just can't find the keywords (and I've been searching a lot), I think it's pretty much what Boost::Bind() does, so it must exist. Can you help me ?

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  • Translate sequence in macro parameters to separate macros

    - by Alex Tiger
    How to acces each element in macro if the definition is like MACRO(name, seq) and the code is like: MACRO("TheName", (Elem1) (Elem2) (Elem3) ) I want to generate the next code: MACRO("TheName", ELEMMACRO(Elem1) ELEMMACRO(Elem2) ELEMMACRO(Elem3) ) Or something like that. In other words, I want to process every parameter separately (I don't care of definition, even if it will be something like MACRO("TheName", Elem1, Elem2, Elem3 ) There could be more elements, there could be less. I have tried V_ARGS (I need it only for gcc), but I can only copy all the elements by that, not to process them separately. What can I do? P.S. Because of some reasons, I can't use Boost.

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  • Dealing with external processes

    - by Jesse Aldridge
    I've been working on a gui app that needs to manage external processes. Working with external processes leads to a lot of issues that can make a programmer's life difficult. I feel like maintenence on this app is taking an unacceptably long time. I've been trying to list the things that make working with external processes difficult so that I can come up with ways of mitigating the pain. This kind of turned into a rant which I thought I'd post here in order to get some feedback and to provide some guidance to anybody thinking about sailing into these very murky waters. Here's what I've got so far: Output from the child can get mixed up with output from the parent. This can make both outputs misleading and hard to read. It can be hard to tell what came from where. It becomes harder to figure out what's going on when things are asynchronous. Here's a contrived example: import textwrap, os, time from subprocess import Popen test_path = 'test_file.py' with open(test_path, 'w') as file: file.write(textwrap.dedent(''' import time for i in range(3): print 'Hello %i' % i time.sleep(1)''')) proc = Popen('python -B "%s"' % test_path) for i in range(3): print 'Hello %i' % i time.sleep(1) os.remove(test_path) I guess I could have the child process write its output to a file. But it can be annoying to have to open up a file every time I want to see the result of a print statement. If I have code for the child process I could add a label, something like print 'child: Hello %i', but it can be annoying to do that for every print. And it adds some noise to the output. And of course I can't do it if I don't have access to the code. I could manually manage the process output. But then you open up a huge can of worms with threads and polling and stuff like that. A simple solution is to treat processes like synchronous functions, that is, no further code executes until the process completes. In other words, make the process block. But that doesn't work if you're building a gui app. Which brings me to the next problem... Blocking processes cause the gui to become unresponsive. import textwrap, sys, os from subprocess import Popen from PyQt4.QtGui import * from PyQt4.QtCore import * test_path = 'test_file.py' with open(test_path, 'w') as file: file.write(textwrap.dedent(''' import time for i in range(3): print 'Hello %i' % i time.sleep(1)''')) app = QApplication(sys.argv) button = QPushButton('Launch process') def launch_proc(): # Can't move the window until process completes proc = Popen('python -B "%s"' % test_path) proc.communicate() button.connect(button, SIGNAL('clicked()'), launch_proc) button.show() app.exec_() os.remove(test_path) Qt provides a process wrapper of its own called QProcess which can help with this. You can connect functions to signals to capture output relatively easily. This is what I'm currently using. But I'm finding that all these signals behave suspiciously like goto statements and can lead to spaghetti code. I think I want to get sort-of blocking behavior by having the 'finished' signal from QProcess call a function containing all the code that comes after the process call. I think that should work but I'm still a bit fuzzy on the details... Stack traces get interrupted when you go from the child process back to the parent process. If a normal function screws up, you get a nice complete stack trace with filenames and line numbers. If a subprocess screws up, you'll be lucky if you get any output at all. You end up having to do a lot more detective work everytime something goes wrong. Speaking of which, output has a way of disappearing when dealing external processes. Like if you run something via the windows 'cmd' command, the console will pop up, execute the code, and then disappear before you have a chance to see the output. You have to pass the /k flag to make it stick around. Similar issues seem to crop up all the time. I suppose both problems 3 and 4 have the same root cause: no exception handling. Exception handling is meant to be used with functions, it doesn't work with processes. Maybe there's some way to get something like exception handling for processes? I guess that's what stderr is for? But dealing with two different streams can be annoying in itself. Maybe I should look into this more... Processes can hang and stick around in the background without you realizing it. So you end up yelling at your computer cuz it's going so slow until you finally bring up your task manager and see 30 instances of the same process hanging out in the background. Also, hanging background processes can interefere with other instances of the process in various fun ways, such as causing permissions errors by holding a handle to a file or someting like that. It seems like an easy solution to this would be to have the parent process kill the child process on exit if the child process didn't close itself. But if the parent process crashes, cleanup code might not get called and the child can be left hanging. Also, if the parent waits for the child to complete, and the child is in an infinite loop or something, you can end up with two hanging processes. This problem can tie in to problem 2 for extra fun, causing your gui to stop responding entirely and force you to kill everything with the task manager. F***ing quotes Parameters often need to be passed to processes. This is a headache in itself. Especially if you're dealing with file paths. Say... 'C:/My Documents/whatever/'. If you don't have quotes, the string will often be split at the space and interpreted as two arguments. If you need nested quotes you can use ' and ". But if you need to use more than two layers of quotes, you have to do some nasty escaping, for example: "cmd /k 'python \'path 1\' \'path 2\''". A good solution to this problem is passing parameters as a list rather than as a single string. Subprocess allows you to do this. Can't easily return data from a subprocess. You can use stdout of course. But what if you want to throw a print in there for debugging purposes? That's gonna screw up the parent if it's expecting output formatted a certain way. In functions you can print one string and return another and everything works just fine. Obscure command-line flags and a crappy terminal based help system. These are problems I often run into when using os level apps. Like the /k flag I mentioned, for holding a cmd window open, who's idea was that? Unix apps don't tend to be much friendlier in this regard. Hopefully you can use google or StackOverflow to find the answer you need. But if not, you've got a lot of boring reading and frusterating trial and error to do. External factors. This one's kind of fuzzy. But when you leave the relatively sheltered harbor of your own scripts to deal with external processes you find yourself having to deal with the "outside world" to a much greater extent. And that's a scary place. All sorts of things can go wrong. Just to give a random example: the cwd in which a process is run can modify it's behavior. There are probably other issues, but those are the ones I've written down so far. Any other snags you'd like to add? Any suggestions for dealing with these problems?

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  • Developer’s Life – Every Developer is a Captain America

    - by Pinal Dave
    Captain America was first created as a comic book character in the 1940’s as a way to boost morale during World War II.  Aimed at a children’s audience, his legacy faded away when the war ended.  However, he has recently has a major reboot to become a popular movie character that deals with modern issues. When Captain America was first written, there was no such thing as a developer, programmer or a computer (the way we think of them, anyway).  Despite these limitations, I think there are still a lot of ways that modern Captain America is like modern developers. So how are developers like Captain America? Well, read on my list of reasons. Take on Big Projects Captain America isn’t afraid to take on big projects – and takes responsibility when the project is co-opted by the evil organization HYDRA.  Developers may not have super villains out there corrupting their work, but they know to keep on top of their projects and own what they do. Elderly Wisdom Steve Rogers, Captain America’s alter ego, was frozen in ice for decades, and brought back to life to solve problems. Developers can learn from this by respecting the opinions of their elders – technology is an ever-changing market, but the old-timers still have a few tricks up their sleeves! Don’t be Afraid of Change Don’t be afraid of change.  Captain America woke up to find the world he was accustomed to is now completely different.  He might have even felt his skills were no longer necessary.  He, and developers, know that everyone has their place in a team, though.  If you try your best, you will make it work. Fight Your Own Battle Sometimes you have to make it on your own.  Captain America is an integral part of the Avengers, but in his own movies, the other superheroes aren’t around to back him up.  Developers, too, must learn to work both within and with out a team. Solid Integrity One of Captain America’s greatest qualities is his integrity.  His determine to do what is right, keep his word, and act honestly earns him mockery from some of the less-savory characters – even “good guys” like Iron Man.  Developers, and everyone else, need to develop the strength of character to keep their integrity.  No matter your walk of life, there will be tempting obstacles.  Think of Captain America, and say “no.” There is a lot for all of us to learn from Captain America, to take away in our own lives, and admire in those who display it – I am specifically thinking of developers.  If you are enjoying this series as much as I am, please let me know who else you would like to see featured. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL Tagged: Developer, Superhero

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  • Friday Fun: Play 3D Rally Racing in Google Chrome

    - by Asian Angel
    Are you a racing fan in need of a short (or long) break from work? Then get ready to enjoy a mid-day speed boost with the 3D Rally Racing extension for Google Chrome. 3D Rally Racing in Action This is the opening screen for 3D Rally Racing. You can start game play, view current best times, and read through the instructions from here. The first thing that you should do is have a quick look at the instructions to help you get set up and started. Click on “Play” to start the process. Before you can go further you will need to choose a “User Name”. Once you have done that click “Select Track”… Note: The extension will retain your name for later use even if you close your browser. When you first start out you will only have access to two tracks…the others require reaching a certain score/level to unlock them. Once you select a track you will be taken to the next screen. After you have selected a track you will need to choose your car and car color. All that is left to do afterwards is click on “Go Race”. Note: You will be competing against three other vehicles in the race. Here is a look at the “Desert Race Track”… And a look at the “Snow Race Track”. This game moves quickly and it is easy to fall behind if you are not careful! You can have a lot of fun playing this game while you are waiting for the day to end. Conclusion If you love racing games and want a fun way to waste the rest of afternoon at work, then you should definitely give 3D Rally Racing a try. Links Download the 3d Rally Racing extension (Google Chrome Extensions) Similar Articles Productive Geek Tips Friday Fun: Uphill RushFriday Fun: Racing Fun with SuperTuxKart RacerHow to Make Google Chrome Your Default BrowserEnable Vista Black Style Theme for Google Chrome in XPIncrease Google Chrome’s Omnibox Popup Suggestion Count With an Undocumented Switch TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional Enable Check Box Selection in Windows 7 OnlineOCR – Free OCR Service Betting on the Blind Side, a Vanity Fair article 30 Minimal Logo Designs that Say More with Less LEGO Digital Designer – Free Create a Personal Website Quickly using Flavors.me

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  • Friday Fun: Play 3D Rally Racing in Google Chrome

    - by Asian Angel
    Are you a racing fan in need of a short (or long) break from work? Then get ready to enjoy a mid-day speed boost with the 3D Rally Racing extension for Google Chrome. 3D Rally Racing in Action This is the opening screen for 3D Rally Racing. You can start game play, view current best times, and read through the instructions from here. The first thing that you should do is have a quick look at the instructions to help you get set up and started. Click on “Play” to start the process. Before you can go further you will need to choose a “User Name”. Once you have done that click “Select Track”… Note: The extension will retain your name for later use even if you close your browser. When you first start out you will only have access to two tracks…the others require reaching a certain score/level to unlock them. Once you select a track you will be taken to the next screen. After you have selected a track you will need to choose your car and car color. All that is left to do afterwards is click on “Go Race”. Note: You will be competing against three other vehicles in the race. Here is a look at the “Desert Race Track”… And a look at the “Snow Race Track”. This game moves quickly and it is easy to fall behind if you are not careful! You can have a lot of fun playing this game while you are waiting for the day to end. Conclusion If you love racing games and want a fun way to waste the rest of afternoon at work, then you should definitely give 3D Rally Racing a try. Links Download the 3d Rally Racing extension (Google Chrome Extensions) Similar Articles Productive Geek Tips Friday Fun: Uphill RushFriday Fun: Racing Fun with SuperTuxKart RacerHow to Make Google Chrome Your Default BrowserEnable Vista Black Style Theme for Google Chrome in XPIncrease Google Chrome’s Omnibox Popup Suggestion Count With an Undocumented Switch TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional Enable Check Box Selection in Windows 7 OnlineOCR – Free OCR Service Betting on the Blind Side, a Vanity Fair article 30 Minimal Logo Designs that Say More with Less LEGO Digital Designer – Free Create a Personal Website Quickly using Flavors.me

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  • Add Enhanced Balloon Tooltips to Firefox

    - by Asian Angel
    The default balloon tooltip in Firefox does well at times but then there are instances when a person finds that more information would be much better. The Tooltip Plus extension for Firefox will give your browser that nice extra information boost. Before & After For our example we have placed the “before & after shots” together for better comparison. First off we started with the How-To Geek logo. Note: Does not display the original URL behind shortened URLs. Next we moved on to a permanently linked article title. The “Reviews Tab” in the How-To Geek website toolbar. The article tags listing just beneath the HTG website toolbar. And the link for subscribing to our RSS Feed. In each instance you could actually see the address behind the links. The Tooltip Plus extension will also help out with images in webpages (including “Alt Text” if present). Notice that the link for the image is now available for you to view. Options The options are extremely simple to work with. Decide if you want a document icon to display, the size of the icon, and if you would like “Alt Text” for images to be displayed or not. Conclusion The Tooltip Plus extension does one thing and does it very well…it gives you that extra bit of information when you need it. Links Download the Tooltip Plus extension (Mozilla Add-ons) Similar Articles Productive Geek Tips How To Fix System Tray Tooltips Not Displaying in Windows XPStop the Annoying "There are unused icons on your desktop" Popup BalloonThe Illustrated Guide to the New Firefox 3.6 Windows 7 IntegrationView URLs as Tooltips in FirefoxDisable the Annoying “This device can perform faster” Balloon Message in Windows 7 TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional Quickly Switch between Tabs in IE Windows Media Player 12: Tweak Video & Sound with Playback Enhancements Own a cell phone, or does a cell phone own you? Make your Joomla & Drupal Sites Mobile with OSMOBI Integrate Twitter and Delicious and Make Life Easier Design Your Web Pages Using the Golden Ratio

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  • Tom Cruise: Meet Fusion Apps UX and Feel the Speed

    - by ultan o'broin
    Unfortunately, I am old enough to remember, and now to admit that I really loved, the movie Top Gun. You know the one - Tom Cruise, US Navy F-14 ace pilot, Mr Maverick, crisis of confidence, meets woman, etc., etc. Anyway, one of more memorable lines (there were a few) was: "I feel the need, the need for speed." I was reminded of Tom Cruise recently. Paraphrasing a certain Senior Vice President talking about Oracle Fusion Applications and user experience at an all-hands meeting, I heard that: Applications can never be too easy to use. Performance can never be too fast. Developers, assume that your code is always "on". Perfect. You cannot overstate the user experience importance of application speed to users, or at least their perception of speed. We all want that super speed of execution and performance, and increasingly so as enterprise users bring the expectations of consumer IT into the work environment. Sten Vesterli (@stenvesterli), an Oracle Fusion Applications User Experience Advocate, also addressed the speed point artfully at an Oracle Usability Advisory Board meeting in Geneva. Sten asked us that when we next Googled something, to think about the message we see that Google has found hundreds of thousands or millions of results for us in a split second (for example, About 8,340,000 results (0.23 seconds)). Now, how many results can we see and how many can we use immediately? Yet, this simple message communicating the total results available to us works a special magic about speed, delight, and excitement that Google has made its own in the search space. And, guess what? The Oracle Application Development Framework table component relies on a similar "virtual performance boost", says Sten, when it displays the first 50 records in a table, and uses a scrollbar indicating the total size of the data record set. The user scrolls and the application automatically retrieves more records as needed. Application speed and its perception by users is worth bearing in mind the next time you're at a customer site and the IT Department demands that you retrieve every record from the database. Just think of... Dave Ensor: I'll give you all the rows you ask for in one second. If you promise to use them. (Again, hat tip to Sten.) And then maybe think of... Tom Cruise. And if you want to read about the speed of Oracle Fusion Applications, and what that really means in terms of user productivity for your entire business, then check out the Oracle Applications User Experience Oracle Fusion Applications white papers on the usable apps website.

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  • ANTS CLR and Memory Profiler In Depth Review (Part 1 of 2 &ndash; CLR Profiler)

    - by ToStringTheory
    One of the things that people might not know about me, is my obsession to make my code as efficient as possible.  Many people might not realize how much of a task or undertaking that this might be, but it is surely a task as monumental as climbing Mount Everest, except this time it is a challenge for the mind…  In trying to make code efficient, there are many different factors that play a part – size of project or solution, tiers, language used, experience and training of the programmer, technologies used, maintainability of the code – the list can go on for quite some time. I spend quite a bit of time when developing trying to determine what is the best way to implement a feature to accomplish the efficiency that I look to achieve.  One program that I have recently come to learn about – Red Gate ANTS Performance (CLR) and Memory profiler gives me tools to accomplish that job more efficiently as well.  In this review, I am going to cover some of the features of the ANTS profiler set by compiling some hideous example code to test against. Notice As a member of the Geeks With Blogs Influencers program, one of the perks is the ability to review products, in exchange for a free license to the program.  I have not let this affect my opinions of the product in any way, and Red Gate nor Geeks With Blogs has tried to influence my opinion regarding this product in any way. Introduction The ANTS Profiler pack provided by Red Gate was something that I had not heard of before receiving an email regarding an offer to review it for a license.  Since I look to make my code efficient, it was a no brainer for me to try it out!  One thing that I have to say took me by surprise is that upon downloading the program and installing it you fill out a form for your usual contact information.  Sure enough within 2 hours, I received an email from a sales representative at Red Gate asking if she could help me to achieve the most out of my trial time so it wouldn’t go to waste.  After replying to her and explaining that I was looking to review its feature set, she put me in contact with someone that setup a demo session to give me a quick rundown of its features via an online meeting.  After having dealt with a massive ordeal with one of my utility companies and their complete lack of customer service, Red Gates friendly and helpful representatives were a breath of fresh air, and something I was thankful for. ANTS CLR Profiler The ANTS CLR profiler is the thing I want to focus on the most in this post, so I am going to dive right in now. Install was simple and took no time at all.  It installed both the profiler for the CLR and Memory, but also visual studio extensions to facilitate the usage of the profilers (click any images for full size images): The Visual Studio menu options (under ANTS menu) Starting the CLR Performance Profiler from the start menu yields this window If you follow the instructions after launching the program from the start menu (Click File > New Profiling Session to start a new project), you are given a dialog with plenty of options for profiling: The New Session dialog.  Lots of options.  One thing I noticed is that the buttons in the lower right were half-covered by the panel of the application.  If I had to guess, I would imagine that this is caused by my DPI settings being set to 125%.  This is a problem I have seen in other applications as well that don’t scale well to different dpi scales. The profiler options give you the ability to profile: .NET Executable ASP.NET web application (hosted in IIS) ASP.NET web application (hosted in IIS express) ASP.NET web application (hosted in Cassini Web Development Server) SharePoint web application (hosted in IIS) Silverlight 4+ application Windows Service COM+ server XBAP (local XAML browser application) Attach to an already running .NET 4 process Choosing each option provides a varying set of other variables/options that one can set including options such as application arguments, operating path, record I/O performance performance counters to record (43 counters in all!), etc…  All in all, they give you the ability to profile many different .Net project types, and make it simple to do so.  In most cases of my using this application, I would be using the built in Visual Studio extensions, as they automatically start a new profiling project in ANTS with the options setup, and start your program, however RedGate has made it easy enough to profile outside of Visual Studio as well. On the flip side of this, as someone who lives most of their work life in Visual Studio, one thing I do wish is that instead of opening an entirely separate application/gui to perform profiling after launching, that instead they would provide a Visual Studio panel with the information, and integrate more of the profiling project information into Visual Studio.  So, now that we have an idea of what options that the profiler gives us, its time to test its abilities and features. Horrendous Example Code – Prime Number Generator One of my interests besides development, is Physics and Math – what I went to college for.  I have especially always been interested in prime numbers, as they are something of a mystery…  So, I decided that I would go ahead and to test the abilities of the profiler, I would write a small program, website, and library to generate prime numbers in the quantity that you ask for.  I am going to start off with some terrible code, and show how I would see the profiler being used as a development tool. First off, the IPrimes interface (all code is downloadable at the end of the post): interface IPrimes { IEnumerable<int> GetPrimes(int retrieve); } Simple enough, right?  Anything that implements the interface will (hopefully) provide an IEnumerable of int, with the quantity specified in the parameter argument.  Next, I am going to implement this interface in the most basic way: public class DumbPrimes : IPrimes { public IEnumerable<int> GetPrimes(int retrieve) { //store a list of primes already found var _foundPrimes = new List<int>() { 2, 3 }; //if i ask for 1 or two primes, return what asked for if (retrieve <= _foundPrimes.Count()) return _foundPrimes.Take(retrieve); //the next number to look at int _analyzing = 4; //since I already determined I don't have enough //execute at least once, and until quantity is sufficed do { //assume prime until otherwise determined bool isPrime = true; //start dividing at 2 //divide until number is reached, or determined not prime for (int i = 2; i < _analyzing && isPrime; i++) { //if (i) goes into _analyzing without a remainder, //_analyzing is NOT prime if (_analyzing % i == 0) isPrime = false; } //if it is prime, add to found list if (isPrime) _foundPrimes.Add(_analyzing); //increment number to analyze next _analyzing++; } while (_foundPrimes.Count() < retrieve); return _foundPrimes; } } This is the simplest way to get primes in my opinion.  Checking each number by the straight definition of a prime – is it divisible by anything besides 1 and itself. I have included this code in a base class library for my solution, as I am going to use it to demonstrate a couple of features of ANTS.  This class library is consumed by a simple non-MVVM WPF application, and a simple MVC4 website.  I will not post the WPF code here inline, as it is simply an ObservableCollection<int>, a label, two textbox’s, and a button. Starting a new Profiling Session So, in Visual Studio, I have just completed my first stint developing the GUI and DumbPrimes IPrimes class, so now I want to check my codes efficiency by profiling it.  All I have to do is build the solution (surprised initiating a profiling session doesn’t do this, but I suppose I can understand it), and then click the ANTS menu, followed by Profile Performance.  I am then greeted by the profiler starting up and already monitoring my program live: You are provided with a realtime graph at the top, and a pane at the bottom giving you information on how to proceed.  I am going to start by asking my program to show me the first 15000 primes: After the program finally began responding again (I did all the work on the main UI thread – how bad!), I stopped the profiler, which did kill the process of my program too.  One important thing to note, is that the profiler by default wants to give you a lot of detail about the operation – line hit counts, time per line, percent time per line, etc…  The important thing to remember is that this itself takes a lot of time.  When running my program without the profiler attached, it can generate the 15000 primes in 5.18 seconds, compared to 74.5 seconds – almost a 1500 percent increase.  While this may seem like a lot, remember that there is a trade off.  It may be WAY more inefficient, however, I am able to drill down and make improvements to specific problem areas, and then decrease execution time all around. Analyzing the Profiling Session After clicking ‘Stop Profiling’, the process running my application stopped, and the entire execution time was automatically selected by ANTS, and the results shown below: Now there are a number of interesting things going on here, I am going to cover each in a section of its own: Real Time Performance Counter Bar (top of screen) At the top of the screen, is the real time performance bar.  As your application is running, this will constantly update with the currently selected performance counters status.  A couple of cool things to note are the fact that you can drag a selection around specific time periods to drill down the detail views in the lower 2 panels to information pertaining to only that period. After selecting a time period, you can bookmark a section and name it, so that it is easy to find later, or after reloaded at a later time.  You can also zoom in, out, or fit the graph to the space provided – useful for drilling down. It may be hard to see, but at the top of the processor time graph below the time ticks, but above the red usage graph, there is a green bar. This bar shows at what times a method that is selected in the ‘Call tree’ panel is called. Very cool to be able to click on a method and see at what times it made an impact. As I said before, ANTS provides 43 different performance counters you can hook into.  Click the arrow next to the Performance tab at the top will allow you to change between different counters if you have them selected: Method Call Tree, ADO.Net Database Calls, File IO – Detail Panel Red Gate really hit the mark here I think. When you select a section of the run with the graph, the call tree populates to fill a hierarchical tree of method calls, with information regarding each of the methods.   By default, methods are hidden where the source is not provided (framework type code), however, Red Gate has integrated Reflector into ANTS, so even if you don’t have source for something, you can select a method and get the source if you want.  Methods are also hidden where the impact is seen as insignificant – methods that are only executed for 1% of the time of the overall calling methods time; in other words, working on making them better is not where your efforts should be focused. – Smart! Source Panel – Detail Panel The source panel is where you can see line level information on your code, showing the code for the currently selected method from the Method Call Tree.  If the code is not available, Reflector takes care of it and shows the code anyways! As you can notice, there does seem to be a problem with how ANTS determines what line is the actual line that a call is completed on.  I have suspicions that this may be due to some of the inline code optimizations that the CLR applies upon compilation of the assembly.  In a method with comments, the problem is much more severe: As you can see here, apparently the most offending code in my base library was a comment – *gasp*!  Removing the comments does help quite a bit, however I hope that Red Gate works on their counter algorithm soon to improve the logic on positioning for statistics: I did a small test just to demonstrate the lines are correct without comments. For me, it isn’t a deal breaker, as I can usually determine the correct placements by looking at the application code in the region and determining what makes sense, but it is something that would probably build up some irritation with time. Feature – Suggest Method for Optimization A neat feature to really help those in need of a pointer, is the menu option under tools to automatically suggest methods to optimize/improve: Nice feature – clicking it filters the call tree and stars methods that it thinks are good candidates for optimization.  I do wish that they would have made it more visible for those of use who aren’t great on sight: Process Integration I do think that this could have a place in my process.  After experimenting with the profiler, I do think it would be a great benefit to do some development, testing, and then after all the bugs are worked out, use the profiler to check on things to make sure nothing seems like it is hogging more than its fair share.  For example, with this program, I would have developed it, ran it, tested it – it works, but slowly. After looking at the profiler, and seeing the massive amount of time spent in 1 method, I might go ahead and try to re-implement IPrimes (I actually would probably rewrite the offending code, but so that I can distribute both sets of code easily, I’m just going to make another implementation of IPrimes).  Using two pieces of knowledge about prime numbers can make this method MUCH more efficient – prime numbers fall into two buckets 6k+/-1 , and a number is prime if it is not divisible by any other primes before it: public class SmartPrimes : IPrimes { public IEnumerable<int> GetPrimes(int retrieve) { //store a list of primes already found var _foundPrimes = new List<int>() { 2, 3 }; //if i ask for 1 or two primes, return what asked for if (retrieve <= _foundPrimes.Count()) return _foundPrimes.Take(retrieve); //the next number to look at int _k = 1; //since I already determined I don't have enough //execute at least once, and until quantity is sufficed do { //assume prime until otherwise determined bool isPrime = true; int potentialPrime; //analyze 6k-1 //assign the value to potential potentialPrime = 6 * _k - 1; //if there are any primes that divise this, it is NOT a prime number //using PLINQ for quick boost isPrime = !_foundPrimes.AsParallel() .Any(prime => potentialPrime % prime == 0); //if it is prime, add to found list if (isPrime) _foundPrimes.Add(potentialPrime); if (_foundPrimes.Count() == retrieve) break; //analyze 6k+1 //assign the value to potential potentialPrime = 6 * _k + 1; //if there are any primes that divise this, it is NOT a prime number //using PLINQ for quick boost isPrime = !_foundPrimes.AsParallel() .Any(prime => potentialPrime % prime == 0); //if it is prime, add to found list if (isPrime) _foundPrimes.Add(potentialPrime); //increment k to analyze next _k++; } while (_foundPrimes.Count() < retrieve); return _foundPrimes; } } Now there are definitely more things I can do to help make this more efficient, but for the scope of this example, I think this is fine (but still hideous)! Profiling this now yields a happy surprise 27 seconds to generate the 15000 primes with the profiler attached, and only 1.43 seconds without.  One important thing I wanted to call out though was the performance graph now: Notice anything odd?  The %Processor time is above 100%.  This is because there is now more than 1 core in the operation.  A better label for the chart in my mind would have been %Core time, but to each their own. Another odd thing I noticed was that the profiler seemed to be spot on this time in my DumbPrimes class with line details in source, even with comments..  Odd. Profiling Web Applications The last thing that I wanted to cover, that means a lot to me as a web developer, is the great amount of work that Red Gate put into the profiler when profiling web applications.  In my solution, I have a simple MVC4 application setup with 1 page, a single input form, that will output prime values as my WPF app did.  Launching the profiler from Visual Studio as before, nothing is really different in the profiler window, however I did receive a UAC prompt for a Red Gate helper app to integrate with the web server without notification. After requesting 500, 1000, 2000, and 5000 primes, and looking at the profiler session, things are slightly different from before: As you can see, there are 4 spikes of activity in the processor time graph, but there is also something new in the call tree: That’s right – ANTS will actually group method calls by get/post operations, so it is easier to find out what action/page is giving the largest problems…  Pretty cool in my mind! Overview Overall, I think that Red Gate ANTS CLR Profiler has a lot to offer, however I think it also has a long ways to go.  3 Biggest Pros: Ability to easily drill down from time graph, to method calls, to source code Wide variety of counters to choose from when profiling your application Excellent integration/grouping of methods being called from web applications by request – BRILLIANT! 3 Biggest Cons: Issue regarding line details in source view Nit pick – Processor time vs. Core time Nit pick – Lack of full integration with Visual Studio Ratings Ease of Use (7/10) – I marked down here because of the problems with the line level details and the extra work that that entails, and the lack of better integration with Visual Studio. Effectiveness (10/10) – I believe that the profiler does EXACTLY what it purports to do.  Especially with its large variety of performance counters, a definite plus! Features (9/10) – Besides the real time performance monitoring, and the drill downs that I’ve shown here, ANTS also has great integration with ADO.Net, with the ability to show database queries run by your application in the profiler.  This, with the line level details, the web request grouping, reflector integration, and various options to customize your profiling session I think create a great set of features! Customer Service (10/10) – My entire experience with Red Gate personnel has been nothing but good.  their people are friendly, helpful, and happy! UI / UX (8/10) – The interface is very easy to get around, and all of the options are easy to find.  With a little bit of poking around, you’ll be optimizing Hello World in no time flat! Overall (8/10) – Overall, I am happy with the Performance Profiler and its features, as well as with the service I received when working with the Red Gate personnel.  I WOULD recommend you trying the application and seeing if it would fit into your process, BUT, remember there are still some kinks in it to hopefully be worked out. My next post will definitely be shorter (hopefully), but thank you for reading up to here, or skipping ahead!  Please, if you do try the product, drop me a message and let me know what you think!  I would love to hear any opinions you may have on the product. Code Feel free to download the code I used above – download via DropBox

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  • A toolset for self improvement and learning [closed]

    - by Sebastian
    Possible Duplicate: I’m having trouble learning I've been working as an IT consultant for 1½ years and I am very passionate about programming. Before that I studied MSc Software Engineering and had both a part time job as a developer for a big telecom company. During that time I also took extra courses and earned a SCJP certificate. I have been continuously reading a lot of books during the last 3½ years. Now to my problem. I want to continue learning and become a really, really good developer. Apart from my daytime job as a full time java developer I have taken university courses in, for me, new languages and paradigms. Most recently, android game development and then functional programming with Scala. I've read books, went to conferences and had a couple of presentations for internal training purposes in our local office. I want to have some advice from other people who have previously been in my situation or currently are. What are you guys doing to keep improving yourselves? Here is some things that I have found are working for me: Reading books I've mostly read books about best practices for programming, OO-design, refactoring, design patterns, tdd. Software craftmanship if you like. I keep a reading list and my current book is Apprenticeship patterns. Taking courses In my country we have a really good system for taking online distance courses. I have also taken one course at coursera.org and a highly recommend that platform. Ive looked at courses at oreilly.com, industriallogic, javaspecialists.eu and they seem to be okay. If someone gives these type of courses a really good review, I can probably convince my boss. Workshops that span over a couple of days would probably be harder, but Ive seen that uncle Bob will have one about refactoring and tdd in 6months not far from here.. :) Are their possibly some online learning platforms that I dont know about? Educational videos I've bought uncle bobs videos from cleancoders.com and I highly recommend them. The only thing I dont like is that they are quite expensive and that he talks about astronomy for ~10 minutes in every episode. Getting certified I had a lot of fun and learned a lot when I studied for the SCJP. I have also done some preparation for the microsoft equivalent but never went for it. I think it is a good when selling yourself as a newly graduated student and also will boost your knowledge if your are interested in it. Now I would like others to start sharing their experiences and possibly give me some advice! BR Sebastian

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  • Using TPL and PLINQ to raise performance of feed aggregator

    - by DigiMortal
    In this posting I will show you how to use Task Parallel Library (TPL) and PLINQ features to boost performance of simple RSS-feed aggregator. I will use here only very basic .NET classes that almost every developer starts from when learning parallel programming. Of course, we will also measure how every optimization affects performance of feed aggregator. Feed aggregator Our feed aggregator works as follows: Load list of blogs Download RSS-feed Parse feed XML Add new posts to database Our feed aggregator is run by task scheduler after every 15 minutes by example. We will start our journey with serial implementation of feed aggregator. Second step is to use task parallelism and parallelize feeds downloading and parsing. And our last step is to use data parallelism to parallelize database operations. We will use Stopwatch class to measure how much time it takes for aggregator to download and insert all posts from all registered blogs. After every run we empty posts table in database. Serial aggregation Before doing parallel stuff let’s take a look at serial implementation of feed aggregator. All tasks happen one after other. internal class FeedClient {     private readonly INewsService _newsService;     private const int FeedItemContentMaxLength = 255;       public FeedClient()     {          ObjectFactory.Initialize(container =>          {              container.PullConfigurationFromAppConfig = true;          });           _newsService = ObjectFactory.GetInstance<INewsService>();     }       public void Execute()     {         var blogs = _newsService.ListPublishedBlogs();           for (var index = 0; index <blogs.Count; index++)         {              ImportFeed(blogs[index]);         }     }       private void ImportFeed(BlogDto blog)     {         if(blog == null)             return;         if (string.IsNullOrEmpty(blog.RssUrl))             return;           var uri = new Uri(blog.RssUrl);         SyndicationContentFormat feedFormat;           feedFormat = SyndicationDiscoveryUtility.SyndicationContentFormatGet(uri);           if (feedFormat == SyndicationContentFormat.Rss)             ImportRssFeed(blog);         if (feedFormat == SyndicationContentFormat.Atom)             ImportAtomFeed(blog);                 }       private void ImportRssFeed(BlogDto blog)     {         var uri = new Uri(blog.RssUrl);         var feed = RssFeed.Create(uri);           foreach (var item in feed.Channel.Items)         {             SaveRssFeedItem(item, blog.Id, blog.CreatedById);         }     }       private void ImportAtomFeed(BlogDto blog)     {         var uri = new Uri(blog.RssUrl);         var feed = AtomFeed.Create(uri);           foreach (var item in feed.Entries)         {             SaveAtomFeedEntry(item, blog.Id, blog.CreatedById);         }     } } Serial implementation of feed aggregator downloads and inserts all posts with 25.46 seconds. Task parallelism Task parallelism means that separate tasks are run in parallel. You can find out more about task parallelism from MSDN page Task Parallelism (Task Parallel Library) and Wikipedia page Task parallelism. Although finding parts of code that can run safely in parallel without synchronization issues is not easy task we are lucky this time. Feeds import and parsing is perfect candidate for parallel tasks. We can safely parallelize feeds import because importing tasks doesn’t share any resources and therefore they don’t also need any synchronization. After getting the list of blogs we iterate through the collection and start new TPL task for each blog feed aggregation. internal class FeedClient {     private readonly INewsService _newsService;     private const int FeedItemContentMaxLength = 255;       public FeedClient()     {          ObjectFactory.Initialize(container =>          {              container.PullConfigurationFromAppConfig = true;          });           _newsService = ObjectFactory.GetInstance<INewsService>();     }       public void Execute()     {         var blogs = _newsService.ListPublishedBlogs();                var tasks = new Task[blogs.Count];           for (var index = 0; index <blogs.Count; index++)         {             tasks[index] = new Task(ImportFeed, blogs[index]);             tasks[index].Start();         }           Task.WaitAll(tasks);     }       private void ImportFeed(object blogObject)     {         if(blogObject == null)             return;         var blog = (BlogDto)blogObject;         if (string.IsNullOrEmpty(blog.RssUrl))             return;           var uri = new Uri(blog.RssUrl);         SyndicationContentFormat feedFormat;           feedFormat = SyndicationDiscoveryUtility.SyndicationContentFormatGet(uri);           if (feedFormat == SyndicationContentFormat.Rss)             ImportRssFeed(blog);         if (feedFormat == SyndicationContentFormat.Atom)             ImportAtomFeed(blog);                }       private void ImportRssFeed(BlogDto blog)     {          var uri = new Uri(blog.RssUrl);          var feed = RssFeed.Create(uri);           foreach (var item in feed.Channel.Items)          {              SaveRssFeedItem(item, blog.Id, blog.CreatedById);          }     }     private void ImportAtomFeed(BlogDto blog)     {         var uri = new Uri(blog.RssUrl);         var feed = AtomFeed.Create(uri);           foreach (var item in feed.Entries)         {             SaveAtomFeedEntry(item, blog.Id, blog.CreatedById);         }     } } You should notice first signs of the power of TPL. We made only minor changes to our code to parallelize blog feeds aggregating. On my machine this modification gives some performance boost – time is now 17.57 seconds. Data parallelism There is one more way how to parallelize activities. Previous section introduced task or operation based parallelism, this section introduces data based parallelism. By MSDN page Data Parallelism (Task Parallel Library) data parallelism refers to scenario in which the same operation is performed concurrently on elements in a source collection or array. In our code we have independent collections we can process in parallel – imported feed entries. As checking for feed entry existence and inserting it if it is missing from database doesn’t affect other entries the imported feed entries collection is ideal candidate for parallelization. internal class FeedClient {     private readonly INewsService _newsService;     private const int FeedItemContentMaxLength = 255;       public FeedClient()     {          ObjectFactory.Initialize(container =>          {              container.PullConfigurationFromAppConfig = true;          });           _newsService = ObjectFactory.GetInstance<INewsService>();     }       public void Execute()     {         var blogs = _newsService.ListPublishedBlogs();                var tasks = new Task[blogs.Count];           for (var index = 0; index <blogs.Count; index++)         {             tasks[index] = new Task(ImportFeed, blogs[index]);             tasks[index].Start();         }           Task.WaitAll(tasks);     }       private void ImportFeed(object blogObject)     {         if(blogObject == null)             return;         var blog = (BlogDto)blogObject;         if (string.IsNullOrEmpty(blog.RssUrl))             return;           var uri = new Uri(blog.RssUrl);         SyndicationContentFormat feedFormat;           feedFormat = SyndicationDiscoveryUtility.SyndicationContentFormatGet(uri);           if (feedFormat == SyndicationContentFormat.Rss)             ImportRssFeed(blog);         if (feedFormat == SyndicationContentFormat.Atom)             ImportAtomFeed(blog);                }       private void ImportRssFeed(BlogDto blog)     {         var uri = new Uri(blog.RssUrl);         var feed = RssFeed.Create(uri);           feed.Channel.Items.AsParallel().ForAll(a =>         {             SaveRssFeedItem(a, blog.Id, blog.CreatedById);         });      }        private void ImportAtomFeed(BlogDto blog)      {         var uri = new Uri(blog.RssUrl);         var feed = AtomFeed.Create(uri);           feed.Entries.AsParallel().ForAll(a =>         {              SaveAtomFeedEntry(a, blog.Id, blog.CreatedById);         });      } } We did small change again and as the result we parallelized checking and saving of feed items. This change was data centric as we applied same operation to all elements in collection. On my machine I got better performance again. Time is now 11.22 seconds. Results Let’s visualize our measurement results (numbers are given in seconds). As we can see then with task parallelism feed aggregation takes about 25% less time than in original case. When adding data parallelism to task parallelism our aggregation takes about 2.3 times less time than in original case. More about TPL and PLINQ Adding parallelism to your application can be very challenging task. You have to carefully find out parts of your code where you can safely go to parallel processing and even then you have to measure the effects of parallel processing to find out if parallel code performs better. If you are not careful then troubles you will face later are worse than ones you have seen before (imagine error that occurs by average only once per 10000 code runs). Parallel programming is something that is hard to ignore. Effective programs are able to use multiple cores of processors. Using TPL you can also set degree of parallelism so your application doesn’t use all computing cores and leaves one or more of them free for host system and other processes. And there are many more things in TPL that make it easier for you to start and go on with parallel programming. In next major version all .NET languages will have built-in support for parallel programming. There will be also new language constructs that support parallel programming. Currently you can download Visual Studio Async to get some idea about what is coming. Conclusion Parallel programming is very challenging but good tools offered by Visual Studio and .NET Framework make it way easier for us. In this posting we started with feed aggregator that imports feed items on serial mode. With two steps we parallelized feed importing and entries inserting gaining 2.3 times raise in performance. Although this number is specific to my test environment it shows clearly that parallel programming may raise the performance of your application significantly.

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  • SQL SERVER – Iridium I/O – SQL Server Deduplication that Shrinks Databases and Improves Performance

    - by Pinal Dave
    Database performance is a common problem for SQL Server DBA’s.  It seems like we spend more time on performance than just about anything else.  In many cases, we use scripts or tools that point out performance bottlenecks but we don’t have any way to fix them.  For example, what do you do when you need to speed up a query that is already tuned as well as possible?  Or what do you do when you aren’t allowed to make changes for a database supporting a purchased application? Iridium I/O for SQL Server was originally built at Confio software (makers of Ignite) because DBA’s kept asking for a way to actually fix performance instead of just pointing out performance problems. The technology is certified by Microsoft and was so promising that it was spun out into a separate company that is now run by the Confio Founder/CEO and technology management team. Iridium uses deduplication technology to both shrink the databases as well as boost IO performance.  It is intriguing to see it work.  It will deduplicate a live database as it is running transactions.  You can watch the database get smaller while user queries are running. Iridium is a simple tool to use. After installing the software, you click an “Analyze” button which will spend a minute or two on each database and estimate both your storage and performance savings.  Next, you click an “Activate” button to turn on Iridium I/O for your selected databases.  You don’t need to reboot the operating system or restart the database during any part of the process. As part of my test, I also wanted to see if there would be an impact on my databases when Iridium was removed.  The ‘revert’ process (bringing the files back to their SQL Server native format) was executed by a simple click of a button, and completed while the databases were available for normal processing. I was impressed and enjoyed playing with the software and encourage all of you to try it out.  Here is the link to the website to download Iridium for free. . Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Performance, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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