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  • jqGrid dynamic event

    - by Daveo
    Suppose I have the following (shortened for simplicity): jQuery("#grid").jqGrid({ ... ondblClickRow: function() { // I want to define this function dynamically at run time } ... }); How to I bind ondblClickRow event outside of the grid Deceleration. For example in jQuery I would normally do $('#grid').bind('ondblClickRow', function() { alert('my over written event'); });

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  • Install driver and copying files before Installation runs

    - by Kazoom
    I have created installation package for my project, but before or after installation is complete i need to install some drivers and copy some files to target machine, before my software can run. Is it possible for me to do all this action in the MSI installer setup project of visual studio 2005. One option i have explored is using autoITscript, is there a better approach than that? i feel able to do the whole thing in visual studio would be an ideal way? any suggestions? Thanks

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  • Where is the node.js file in the stack trace located?

    - by user225189
    Obviously, I'm pretty new to node.js. I'm attempting to debug a node.js application and I see node.js in the stack trace. I would like to put some sys.puts calls in there, but I cannot locate the node.js that is being run by my server. Is there a way to tell where node.js is located? Is there an equivalent to Ruby's FILE in node? Thanks, Brian

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  • Extending Jquery validate to show/hide div or clear div after validate is ran

    - by Shawn
    Right now i have all of my errors outputting to a div. Id like to catch the validate event and clear the div right before its ran of my old errors. Then id like to show/hide that div based on if it has any labels in it that were auto generated by the jquery validation plugin. I can do everything but figure out how to extend the event, run the stuff i need to, then call the validate function. Thanks!

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  • C++ Builder 2010 How to switch to FASTMM

    - by James
    Hello I have some projects which were done in c++ builder 2009 and they need borlandmm.dll to run. I have read that c++ Builder 2010 by default use Fastmm, but it dont seems to be the case in my projects. They still need borlandmm.dll So how can i switch my projects to use fastmm ? Regards James

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  • Great non-obvious java tricks

    - by folone
    Consider having a class: public class Test { public static void main(String [] args) { for (int i = 0; i < args.length; i++) { System.out.println(args[i]); } } } What happens if you run it: java Test *? Answer: it prints out all the filenames in current directory. Got more such tricks?

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  • Variables are "lost" somewhere, then reappear... all with no error thrown.

    - by rob - not a robber
    Hi All, I'm probably going to make myself look like a fool with my horrible scripting but here we go. I have a form that I am collecting a bunch of checkbox info from using a binary method. ON/SET=1 !ISSET=0 Anyway, all seems to be going as planned except for the query bit. When I run the script, it runs through and throws no errors, but it's not doing what I think I am telling it to. I've hard coded the values in the query and left them in the script and it DOES update the DB. I've also tried echoing all the needed variables after the script runs and exiting right after so I can audit them... and they're all there. Here's an example. ####FEATURES RECORD UPDATE ### HERE I DECIDE TO RUN THE SCRIPT BASED ON WHETHER AN IMAGE BUTTON WAS USED if (isset($_POST["button_x"])) { ### HERE I AM ASSIGNING 1 OR 0 TO A VAR BASED ON WHTER THE CHECKBOX WAS SET if (isset($_POST["pool"])) $pool=1; if (!isset($_POST["pool"])) $pool=0; if (isset($_POST["darts"])) $darts=1; if (!isset($_POST["darts"])) $darts=0; if (isset($_POST["karaoke"])) $karaoke=1; if (!isset($_POST["karaoke"])) $karaoke=0; if (isset($_POST["trivia"])) $trivia=1; if (!isset($_POST["trivia"])) $trivia=0; if (isset($_POST["wii"])) $wii=1; if (!isset($_POST["wii"])) $wii=0; if (isset($_POST["guitarhero"])) $guitarhero=1; if (!isset($_POST["guitarhero"])) $guitarhero=0; if (isset($_POST["megatouch"])) $megatouch=1; if (!isset($_POST["megatouch"])) $megatouch=0; if (isset($_POST["arcade"])) $arcade=1; if (!isset($_POST["arcade"])) $arcade=0; if (isset($_POST["jukebox"])) $jukebox=1; if (!isset($_POST["jukebox"])) $jukebox=0; if (isset($_POST["dancefloor"])) $dancefloor=1; if (!isset($_POST["dancefloor"])) $dancefloor=0; ### I'VE DONE LOADS OF PERMUTATIONS HERE... HARD SET THE 1/0 VARS AND LEFT THE $estab_id TO BE PICKED UP. SET THE $estab_id AND LEFT THE COLUMN DATA TO BE PICKED UP. ALL NO GOOD. IT _DOES_ WORK IF I HARD SET ALL VARS THOUGH mysql_query("UPDATE thedatabase SET pool_table='$pool', darts='$darts', karoke='$karaoke', trivia='$trivia', wii='$wii', megatouch='$megatouch', guitar_hero='$guitarhero', arcade_games='$arcade', dancefloor='$dancefloor' WHERE establishment_id='22'"); ###WEIRD THING HERE IS IF I ECHO THE VARS AT THIS POINT AND THEN EXIT(); they all show up as intended. header("location:theadminfilething.php"); exit(); THANKS ALL!!!

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  • What are codepad.org's Perl runner limitations?

    - by Lemurik
    Sometimes I see people use http://codepad.org as a way to quickly run/test their Perl snippets (it supports doing that with a wide variety of languages, from C to Scheme to Perl). It's pretty obvious that there must be some limitations as to what code/features can be tested with codepad - does anyone know what those limitations are for Perl runner? I'll get the ball rolling on my own observation: not every CPAN module is available :(

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  • WPF Choppy Animation

    - by Chris Dunaway
    WPF Windows-XP SP3 I'm having a problem with a simple WPF animation. I use the following Xaml code (in XamlPad and also in a WPF project): <Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:sys="clr-namespace:System;assembly=mscorlib" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" > <Border Name="MyBorder" BorderThickness="10" BorderBrush="Blue" CornerRadius="10" Background="DarkRed" > <Rectangle Name="MyRectangle" Margin="10" StrokeDashArray="2.0,1.0" StrokeThickness="10" RadiusX="10" RadiusY="10" Stroke="Black" StrokeDashOffset="0"> <Rectangle.Triggers> <EventTrigger RoutedEvent="Rectangle.Loaded"> <BeginStoryboard> <Storyboard> <DoubleAnimation Storyboard.TargetName="MyRectangle" Storyboard.TargetProperty="StrokeDashOffset" From="0.0" To="3.0" Duration="0:0:1" RepeatBehavior="Forever" Timeline.DesiredFrameRate="30" /> </Storyboard> </BeginStoryboard> </EventTrigger> </Rectangle.Triggers> </Rectangle> </Border> </Page> It has the effect of causing the border to animate around the rectangle. After a fresh reboot of the machine, this animation is nice and smooth. However, I tend to leave my machine on all the time and after a period time elapses (I don't know how long), the animation starts stuttering and becomes choppy. I thought that it may be memory or resource issues, but after shutting down all other apps and any services that seem unnecessary, the stuttering still continues. However, after a system reboot, the animation is smooth again! I get the same symptoms in a WPF app or in XamlPad. In the case of the app, it doesn't seem to make any difference whether I run in the debugger or if I run the executable directly. I applied the patch at this link: http://support.microsoft.com/kb/981741 and I thought that it had taken care of the issue, but it seems not to have. I have seen some posts that might indicate that using transparency might affect animation, but as you can see, my xaml does not use transparency. Can anyone give me some suggestions on how to determine what the problem is? Are there any WPF diagnostic tools that might help? UPDATE: I have checked my video drivers and they are the latest version. (nVidia GeForce 8400 GS)

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  • Problem in JSF2 with client-side state saving and serialization

    - by marcel
    I have a problem in JSF2 with client side state saving and serialization. I have created a page with a full description and a small class diagram: http://tinyurl.com/jsf2serial. For the client-side state saving I have to implement Serializable at the classes Search, BackingBean and Connection. The exception that was thrown is: java.io.NotSerializableException: org.apache.commons.httpclient.HttpClient at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1156) at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1509) at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1474) at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1392) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1150) at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1509) at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1474) at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1392) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1150) at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1509) at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1474) at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1392) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1150) at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:326) at java.util.HashMap.writeObject(HashMap.java:1001) at sun.reflect.GeneratedMethodAccessor80.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:945) at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1461) at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1392) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1150) at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1509) at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1474) at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1392) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1150) at java.io.ObjectOutputStream.writeArray(ObjectOutputStream.java:1338) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1146) at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:326) at java.util.HashMap.writeObject(HashMap.java:1001) at sun.reflect.GeneratedMethodAccessor80.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:945) at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1461) at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1392) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1150) at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:326) at com.sun.faces.renderkit.ClientSideStateHelper.doWriteState(ClientSideStateHelper.java:293) at com.sun.faces.renderkit.ClientSideStateHelper.writeState(ClientSideStateHelper.java:167) at com.sun.faces.renderkit.ResponseStateManagerImpl.writeState(ResponseStateManagerImpl.java:123) at com.sun.faces.application.StateManagerImpl.writeState(StateManagerImpl.java:155) at com.sun.faces.application.view.WriteBehindStateWriter.flushToWriter(WriteBehindStateWriter.java:221) at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:397) at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:126) at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:127) at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101) at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139) at javax.faces.webapp.FacesServlet.service(FacesServlet.java:313) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:852) at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588) at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489) at java.lang.Thread.run(Thread.java:637) Maybe this is a problem of my design, because I am new in developing Java webapps.

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  • Crazy VS Designer Errors

    - by BlueRaja
    Here's a strange one. After renaming a class, one of my forms began giving me errors in the designer, refusing to open. Funny thing is, the form worked just fine when I ran the program. I began reverting my changes to deduce the problem. I have now reverted completely back to the last commit - in which I know the form was working in the designer - cleaned the solution, and deleted the bin/ and obj/ folders, as well as the *.suo file for good measure. The form still does not display in designer. Here are the errors it gives: Could not find 'MyNamespace.MyControl'. Please make sure that the assembly that contains this type is referenced. If this type is a part of your development project, make sure that the project has been successfully built. The variable 'myControl1' is either undeclared or was never assigned. The variable is both declared and assigned, and MyControl builds fine (again, the form works fine when the program is actually run). Stranger still, if I try to create a new form and drag a MyControl onto it, I get this Entity-Framework error: Failed to create component 'MyControl'. The error message follows: 'System.ArgumentException: The specified named connection is either not found in the configuration, not intended to be used with the EntityClient provider, or not valid. at System.Data.EntityClient.EntityConnection.ChangeConnectionString(String newConnectionString) at System.Data.EntityClient.EntityConnection..ctor(String connectionString) at System.Data.Objects.ObjectContect.CreateEntityConnection(String connectionString) etc. etc. There is nothing wrong with my connection string: it worked before, and, again, it works when I actually run the program (the control already exists on the old form from the previous commit). Any ideas whatsoever? I am completely at a loss. [Edit] The only significant code: MyControl.cs public MyControl() { _entities = new MyEFEntities(); //Entity-framework generated class } MyForm.Designer.cs private void InitializeComponent() { this.myControl1 = new MyNamespace.MyControl(); ... this.Controls.Add(this.myControl1); } MyEFDatabase.Designer.cs public MyEFEntities() : base("name=MyEFEntities", "MyEFEntities") { ... } App.Config <connectionStrings> <add name="MyEFEntities" connectionString="metadata=res://*/MyEFDatabase.csdl|res://*/MyEFDatabase.ssdl|res://*/MyEFDatabase.msl;provider=System.Data.SqlClient;provider connection string=&quot;Data Source=MyDatabaseServer;Initial Catalog=MyDatabase;Integrated Security=True;MultipleActiveResultSets=True&quot;" providerName="System.Data.EntityClient" /> </connectionStrings> I've tried the "replace &quot; with '" trick - didn't help. [Edit2] It is happening to new projects also, but not immediately. Only after fiddling around a bit (it has something to do with adding a many-to-one relationship that EF did not figure out on its own), but I can't figure out the exact steps to reproduce.

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  • Vaadin - GWT error "module xxx may need to be recompiled

    - by John Leonard
    I'm ramping up on Vaadin and I'm getting this javascript alert whenever I try and run the demo apps. GWT module 'com.vaadin.terminal.gwt.DefaultWidgetSet' may need to be recompiled I've tried cleaning the project to no avail. As I said, I'm ramping up so I'm sure there's some simple step I'm missing or a concept I haven't grasped.

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  • Prevent command window showing when NAnt compiling windows forms application

    - by HollyStyles
    I have been playing with creating little windows forms apps without visual studio. I create my source in Notepad++ and compile with a NAnt build file. When I run the application a command window is also displayed as well as the application window. How can I prevent the command window showing up? using System; using System.Drawing; using System.Windows.Forms; using System.Media; using System.IO; namespace mynamespace { class MyForm : Form { public Button btnPlay; MyForm() { this.SuspendLayout(); this.Text = "My Application"; InitialiseForm(); this.ResumeLayout(false); } private void InitialiseForm() { btnPlay = new Button(); btnPlay.Location = new System.Drawing.Point(30,40); btnPlay.Text = "Play"; btnPlay.Click += new System.EventHandler(btnPlay_Click); this.Controls.Add(btnPlay); } protected void btnPlay_Click(object sender, EventArgs e) { string wav = "testing123.wav"; Stream resourceStream = System.Reflection.Assembly.GetExecutingAssembly().GetManifestResourceStream(wav); SoundPlayer player = new SoundPlayer(resourceStream); player.Play(); } public static void Main() { Application.Run(new MyForm()); } } } Build file <?xml version="1.0"?> <project name="myform" default="build" basedir="."> <description>My Form app</description> <property name="debug" value="true" overwrite="false"/> <target name="clean" description="Remove all generated files"> <delete dir="build"/> </target> <target name="build" description="Compile the source" depends="clean"> <mkdir dir="build"/> <csc target="exe" output="build\MyForm.exe" debug="${debug}" verbose="true"> <resources> <include name="app\resources\*.wav" /> </resources> <sources> <include name="app\MyForm.cs"/> </sources> </csc> </target> </project>

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  • How to use SSL Web Services in a Rails application

    - by Mathieu
    Hi, I having a hard time to consume this webservice https://www.arello.com/webservice/verify.cfc?wsdl in my rails application. I successfully generated the ruby files with the wsdl2ruby.rb but when un run the generated script I get the following error: at depth 0 - 20: unable to get local issuer certificate OpenSSL::SSL::SSLError: SSL_connect returned=1 errno=0 state=SSLv3 read server certificate B: certificate verify failed I also tried to connect via this script but same issue require 'http-access2' client = HTTPAccess2::Client.new() client.ssl_config.set_trust_ca('/arello.cert') puts client.get('https://www.arello.com/webservice/verify.cfc?wsdl').content Any ideas? Thanks

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  • Update n number of records using JPA with Optimistic locking

    - by Jacques René Mesrine
    I have a table with a column called "count" and I want to run a cron job that will trigger a statement that performs a SQL like this: update summaryTable set count=4; Note that there might be concurrent threads reading & changing the value for "count" when this cron job is triggered. The table has a version column to support Optimistic Locking. What's an efficient way to update the count in JPA ?

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  • No tests found with test runner 'JUnit 4'

    - by lamisse
    Hello , my java test worked well from Eclipse ,I do not know I relaunch test from run menu and then have the following message: No tests found with test runner 'JUnit 4' In the .classpath file I have all jar files, and at the end have : <classpathentry exported="true" kind="con" path="org.eclipse.jdt.junit.JUNIT_CONTAINER/4"/> <classpathentry kind="output" path="bin"/> </classpath> please help!

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  • Is there some way to "nice" my JavaScript execution?

    - by synapz
    I'd like to run some calculations in a browser window, but I don't want it to slow the client computer down for user interaction, especially for single core machines. Is there some way to adjust the nice level of my executing JavaScript so that it will execute as fast as possible without detracting from the responsiveness of the machine?

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  • how to redirect stdin to java Runtime.exec ?

    - by jprogram2010
    I want to execute some sql scripts using Java's Runtime.exec method. I intend to invoke mysql.exe / mysql.sh and redirect the script file to this process. From the command prompt I can run the command <mysqInstallDir\/bin\mysql.exe -u <userName> -p <password> < scripts\create_tables.sql I can invoke mysql.exe using Runtime.exec but how do I redirect data from sql file to mysql.exe ?

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  • WPF Global Resources in App.xaml

    - by Ryan
    I have created a custom Treeview control and am trying to access the HierarchicalDataTemplate resource of this control from another window in the same project. I have placed <ResourceDictionary Source="/Controls/TreeView/Themes/Generic.xaml"/> into my App.xaml file. Everytime I run, I get an error saying that it can not find the resource key "scene" - the name of the HierarchicalDataTemplate from my custom control. How can I access this template? Thanks

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  • Code::Blocks invalid compiler problem

    - by salifu
    i have installed successfully codeblock on my pc but when i try to run "hello world" or even another code, i get this messege of bluild log "name-Debug uses an invalid compiler. Skipping... nothing to be done" so please help me!

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  • Capture Sql Error when excute in CMD file

    - by sarah xia
    Hi, I am writing a CMD file which runs a bunch of sql files, like this: :: Running every sql file in the temp directory For %%G IN (.\install\*.sql) DO ( :: run sql script echo exit | sqlplus interacct/interacct @%%G ) My question is how do I capture an error when one of the scripts didn't succeed? Thankyou. Sarah

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  • What is the fastest cyclic synchronization in Java (ExecutorService vs. CyclicBarrier vs. X)?

    - by Alex Dunlop
    Which Java synchronization construct is likely to provide the best performance for a concurrent, iterative processing scenario with a fixed number of threads like the one outlined below? After experimenting on my own for a while (using ExecutorService and CyclicBarrier) and being somewhat surprised by the results, I would be grateful for some expert advice and maybe some new ideas. Existing questions here do not seem to focus primarily on performance, hence this new one. Thanks in advance! The core of the app is a simple iterative data processing algorithm, parallelized to the spread the computational load across 8 cores on a Mac Pro, running OS X 10.6 and Java 1.6.0_07. The data to be processed is split into 8 blocks and each block is fed to a Runnable to be executed by one of a fixed number of threads. Parallelizing the algorithm was fairly straightforward, and it functionally works as desired, but its performance is not yet what I think it could be. The app seems to spend a lot of time in system calls synchronizing, so after some profiling I wonder whether I selected the most appropriate synchronization mechanism(s). A key requirement of the algorithm is that it needs to proceed in stages, so the threads need to sync up at the end of each stage. The main thread prepares the work (very low overhead), passes it to the threads, lets them work on it, then proceeds when all threads are done, rearranges the work (again very low overhead) and repeats the cycle. The machine is dedicated to this task, Garbage Collection is minimized by using per-thread pools of pre-allocated items, and the number of threads can be fixed (no incoming requests or the like, just one thread per CPU core). V1 - ExecutorService My first implementation used an ExecutorService with 8 worker threads. The program creates 8 tasks holding the work and then lets them work on it, roughly like this: // create one thread per CPU executorService = Executors.newFixedThreadPool( 8 ); ... // now process data in cycles while( ...) { // package data into 8 work items ... // create one Callable task per work item ... // submit the Callables to the worker threads executorService.invokeAll( taskList ); } This works well functionally (it does what it should), and for very large work items indeed all 8 CPUs become highly loaded, as much as the processing algorithm would be expected to allow (some work items will finish faster than others, then idle). However, as the work items become smaller (and this is not really under the program's control), the user CPU load shrinks dramatically: blocksize | system | user | cycles/sec 256k 1.8% 85% 1.30 64k 2.5% 77% 5.6 16k 4% 64% 22.5 4096 8% 56% 86 1024 13% 38% 227 256 17% 19% 420 64 19% 17% 948 16 19% 13% 1626 Legend: - block size = size of the work item (= computational steps) - system = system load, as shown in OS X Activity Monitor (red bar) - user = user load, as shown in OS X Activity Monitor (green bar) - cycles/sec = iterations through the main while loop, more is better The primary area of concern here is the high percentage of time spent in the system, which appears to be driven by thread synchronization calls. As expected, for smaller work items, ExecutorService.invokeAll() will require relatively more effort to sync up the threads versus the amount of work being performed in each thread. But since ExecutorService is more generic than it would need to be for this use case (it can queue tasks for threads if there are more tasks than cores), I though maybe there would be a leaner synchronization construct. V2 - CyclicBarrier The next implementation used a CyclicBarrier to sync up the threads before receiving work and after completing it, roughly as follows: main() { // create the barrier barrier = new CyclicBarrier( 8 + 1 ); // create Runable for thread, tell it about the barrier Runnable task = new WorkerThreadRunnable( barrier ); // start the threads for( int i = 0; i < 8; i++ ) { // create one thread per core new Thread( task ).start(); } while( ... ) { // tell threads about the work ... // N threads + this will call await(), then system proceeds barrier.await(); // ... now worker threads work on the work... // wait for worker threads to finish barrier.await(); } } class WorkerThreadRunnable implements Runnable { CyclicBarrier barrier; WorkerThreadRunnable( CyclicBarrier barrier ) { this.barrier = barrier; } public void run() { while( true ) { // wait for work barrier.await(); // do the work ... // wait for everyone else to finish barrier.await(); } } } Again, this works well functionally (it does what it should), and for very large work items indeed all 8 CPUs become highly loaded, as before. However, as the work items become smaller, the load still shrinks dramatically: blocksize | system | user | cycles/sec 256k 1.9% 85% 1.30 64k 2.7% 78% 6.1 16k 5.5% 52% 25 4096 9% 29% 64 1024 11% 15% 117 256 12% 8% 169 64 12% 6.5% 285 16 12% 6% 377 For large work items, synchronization is negligible and the performance is identical to V1. But unexpectedly, the results of the (highly specialized) CyclicBarrier seem MUCH WORSE than those for the (generic) ExecutorService: throughput (cycles/sec) is only about 1/4th of V1. A preliminary conclusion would be that even though this seems to be the advertised ideal use case for CyclicBarrier, it performs much worse than the generic ExecutorService. V3 - Wait/Notify + CyclicBarrier It seemed worth a try to replace the first cyclic barrier await() with a simple wait/notify mechanism: main() { // create the barrier // create Runable for thread, tell it about the barrier // start the threads while( ... ) { // tell threads about the work // for each: workerThreadRunnable.setWorkItem( ... ); // ... now worker threads work on the work... // wait for worker threads to finish barrier.await(); } } class WorkerThreadRunnable implements Runnable { CyclicBarrier barrier; @NotNull volatile private Callable<Integer> workItem; WorkerThreadRunnable( CyclicBarrier barrier ) { this.barrier = barrier; this.workItem = NO_WORK; } final protected void setWorkItem( @NotNull final Callable<Integer> callable ) { synchronized( this ) { workItem = callable; notify(); } } public void run() { while( true ) { // wait for work while( true ) { synchronized( this ) { if( workItem != NO_WORK ) break; try { wait(); } catch( InterruptedException e ) { e.printStackTrace(); } } } // do the work ... // wait for everyone else to finish barrier.await(); } } } Again, this works well functionally (it does what it should). blocksize | system | user | cycles/sec 256k 1.9% 85% 1.30 64k 2.4% 80% 6.3 16k 4.6% 60% 30.1 4096 8.6% 41% 98.5 1024 12% 23% 202 256 14% 11.6% 299 64 14% 10.0% 518 16 14.8% 8.7% 679 The throughput for small work items is still much worse than that of the ExecutorService, but about 2x that of the CyclicBarrier. Eliminating one CyclicBarrier eliminates half of the gap. V4 - Busy wait instead of wait/notify Since this app is the primary one running on the system and the cores idle anyway if they're not busy with a work item, why not try a busy wait for work items in each thread, even if that spins the CPU needlessly. The worker thread code changes as follows: class WorkerThreadRunnable implements Runnable { // as before final protected void setWorkItem( @NotNull final Callable<Integer> callable ) { workItem = callable; } public void run() { while( true ) { // busy-wait for work while( true ) { if( workItem != NO_WORK ) break; } // do the work ... // wait for everyone else to finish barrier.await(); } } } Also works well functionally (it does what it should). blocksize | system | user | cycles/sec 256k 1.9% 85% 1.30 64k 2.2% 81% 6.3 16k 4.2% 62% 33 4096 7.5% 40% 107 1024 10.4% 23% 210 256 12.0% 12.0% 310 64 11.9% 10.2% 550 16 12.2% 8.6% 741 For small work items, this increases throughput by a further 10% over the CyclicBarrier + wait/notify variant, which is not insignificant. But it is still much lower-throughput than V1 with the ExecutorService. V5 - ? So what is the best synchronization mechanism for such a (presumably not uncommon) problem? I am weary of writing my own sync mechanism to completely replace ExecutorService (assuming that it is too generic and there has to be something that can still be taken out to make it more efficient). It is not my area of expertise and I'm concerned that I'd spend a lot of time debugging it (since I'm not even sure my wait/notify and busy wait variants are correct) for uncertain gain. Any advice would be greatly appreciated.

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