Comments on: Parallel programming? Well, it’s all about CPU affinity or how to set processor affinity in WPF http://khason.net/blog/parallel-programming-well-it%e2%80%99s-all-about-cpu-affinity-or-how-to-set-processor-affinity-in-wpf/ Take care of the sense, and the sounds will take care of themselves. Tue, 16 Mar 2010 11:21:11 +0000 http://wordpress.org/?v=2.9.2 hourly 1 By: Processor Benchmark http://khason.net/blog/parallel-programming-well-it%e2%80%99s-all-about-cpu-affinity-or-how-to-set-processor-affinity-in-wpf/comment-page-1/#comment-3649 Processor Benchmark Fri, 05 Mar 2010 16:38:32 +0000 http://khason.net/blog/parallel-programming-well-it%e2%80%99s-all-about-cpu-affinity-or-how-to-set-processor-affinity-in-wpf/#comment-3649 Sweet.... This is what I'm looking for Sweet…. This is what I’m looking for

]]> By: Sasha Goldshtein http://khason.net/blog/parallel-programming-well-it%e2%80%99s-all-about-cpu-affinity-or-how-to-set-processor-affinity-in-wpf/comment-page-1/#comment-1312 Sasha Goldshtein Thu, 01 Jan 2009 08:44:30 +0000 http://khason.net/blog/parallel-programming-well-it%e2%80%99s-all-about-cpu-affinity-or-how-to-set-processor-affinity-in-wpf/#comment-1312 <p>Tamir, the reason AppDomain.GetCurrentThreadId() gives you a deprecation warning is that the correlation between CLR threads and OS threads is not guaranteed (as of CLR 2.0).</p> <p>This means two things effectively:</p> <p>1. A single OS thread can host multiple CLR threads (e.g. using fibers or other cooperative scheduling mechanisms)</p> <p>2. A single CLR thread can jump between multiple OS threads</p> <p>In the default CLR host, CLR threads and OS threads are essentially the same, and therefore you can safely ignore this warning, at least with the current CLR version.  However, if you're running under a custom host (such as SQL Server 2005 or your own), then you should be aware of the fact that the OS thread id doesn't mean much.</p> <p>By the way, if you are very concerned about keeping your CLR thread on the same OS thread, then you can call Thread.BeginThreadAffinity and the CLR thread will be tied to the OS thread from that moment on.</p> <p>This also means that using the Win32 API removes the deprecation warning, but the problem remains.  When you call kernel32!GetCurrentThread and kernel32!SetThreadAffinityMask you are changing the affinity of the current underlying OS thread, which is not guaranteed to be the stable OS thread for the current CLR thread.</p> Tamir, the reason AppDomain.GetCurrentThreadId() gives you a deprecation warning is that the correlation between CLR threads and OS threads is not guaranteed (as of CLR 2.0).

This means two things effectively:

1. A single OS thread can host multiple CLR threads (e.g. using fibers or other cooperative scheduling mechanisms)

2. A single CLR thread can jump between multiple OS threads

In the default CLR host, CLR threads and OS threads are essentially the same, and therefore you can safely ignore this warning, at least with the current CLR version.  However, if you’re running under a custom host (such as SQL Server 2005 or your own), then you should be aware of the fact that the OS thread id doesn’t mean much.

By the way, if you are very concerned about keeping your CLR thread on the same OS thread, then you can call Thread.BeginThreadAffinity and the CLR thread will be tied to the OS thread from that moment on.

This also means that using the Win32 API removes the deprecation warning, but the problem remains.  When you call kernel32!GetCurrentThread and kernel32!SetThreadAffinityMask you are changing the affinity of the current underlying OS thread, which is not guaranteed to be the stable OS thread for the current CLR thread.

]]> By: Tamir Khason http://khason.net/blog/parallel-programming-well-it%e2%80%99s-all-about-cpu-affinity-or-how-to-set-processor-affinity-in-wpf/comment-page-1/#comment-1311 Tamir Khason Thu, 01 Jan 2009 08:44:29 +0000 http://khason.net/blog/parallel-programming-well-it%e2%80%99s-all-about-cpu-affinity-or-how-to-set-processor-affinity-in-wpf/#comment-1311 <p>Sasha, you are right. However, if you'll look into my code, you'll see, that from one hand I want to stick to OS thread, but in other section, I want to use fiber thread instead. Thus I do not use it. </p> <p>Parallel extension using original OS threads, rather then fiber thread and I, personally, want to be able to manage it. This is the article about</p> Sasha, you are right. However, if you’ll look into my code, you’ll see, that from one hand I want to stick to OS thread, but in other section, I want to use fiber thread instead. Thus I do not use it.

Parallel extension using original OS threads, rather then fiber thread and I, personally, want to be able to manage it. This is the article about

]]> By: cpuid http://khason.net/blog/parallel-programming-well-it%e2%80%99s-all-about-cpu-affinity-or-how-to-set-processor-affinity-in-wpf/comment-page-1/#comment-1310 cpuid Thu, 01 Jan 2009 08:44:28 +0000 http://khason.net/blog/parallel-programming-well-it%e2%80%99s-all-about-cpu-affinity-or-how-to-set-processor-affinity-in-wpf/#comment-1310 <p>Pingback from  cpuid</p> Pingback from  cpuid

]]> By: cpu roller | Collection of computer-related keywords http://khason.net/blog/parallel-programming-well-it%e2%80%99s-all-about-cpu-affinity-or-how-to-set-processor-affinity-in-wpf/comment-page-1/#comment-1309 cpu roller | Collection of computer-related keywords Thu, 01 Jan 2009 08:44:27 +0000 http://khason.net/blog/parallel-programming-well-it%e2%80%99s-all-about-cpu-affinity-or-how-to-set-processor-affinity-in-wpf/#comment-1309 <p>Pingback from  cpu roller | Collection of computer-related keywords</p> Pingback from  cpu roller | Collection of computer-related keywords

]]> By: cpu roller | computer tags http://khason.net/blog/parallel-programming-well-it%e2%80%99s-all-about-cpu-affinity-or-how-to-set-processor-affinity-in-wpf/comment-page-1/#comment-1308 cpu roller | computer tags Thu, 01 Jan 2009 08:44:25 +0000 http://khason.net/blog/parallel-programming-well-it%e2%80%99s-all-about-cpu-affinity-or-how-to-set-processor-affinity-in-wpf/#comment-1308 <p>Pingback from  cpu roller | computer tags</p> Pingback from  cpu roller | computer tags

]]>