multicore | 易学教程

Is there a way to see how much CPU usage per core a process is using?

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问题 I know in perfmon you can see how much each core is utilized, and how much total CPU a particular process is using. However I can't seem to find a way to see how much CPU a process is using broken down by cores. Is there a built-in way to see this information? Is there a programmatic way to see this? (C# preferred) Am I demonstrating a misunderstanding of how Windows (Vista) handles core usage and context switching by asking this question? Edit: More clarification of what I want to find out.

Where to find Paint.NET multithreading white paper?

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Like I wrote elsewhere , I seem to be sure that a white paper by Rick Brewster about multithreading used in Paint.NET once existed. I am not able to find any reference to this white paper again however. Does it (still) exist? And if so, where? EDIT: Found out in comments to an unrelated question that Paint.NET is still free, but code is no longer available? Is this related to the fact that I can't seem to find that white paper any more? EDIT2: Went straight to the horses mouth on this and will return any answer that I get here. In the meantime any answer you guys might have is more than

How does Perl's threading system work?

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问题 Perl's documentation says: Since Perl 5.8, thread programming has been available using a model called interpreter threads which provides a new Perl interpreter for each thread Using ps -Lm <pid> with the program below I can see that threads run in parallel, i.e., they are being run at the same time in different cores. But even when there are 4 threads (3 and the main) ps aux shows only one Perl process. Does this mean that there is a whole Perl interpreter on each thread? Are Perl threads

How can I get a count of “Available” processors for my application?

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I know how to get the number of physical, and number of logical processors on my machine, but I want to know how many logical processors my application has access to. For instance, I develop on a quad core machine, but I have a number of single core users out there, and in many instances I "dumb down" the interface, or run into locking problems that a multi-core system never experiences. So, to that end I have set up VSTS to build my app in either debug or "Debug Single Core". The goal there is basically to set the processor affinity to core "0", which by looking at the windows task manager is

Can SPARK use multicore properly?

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问题 I've read about spark and I found out that spark is written in scala. Since scala is a functional language, like erlang, it can use multi core properly. Is that correct? I'm wondering if I can use spark in distributed system which have multicore processors. Can a single task use all cores at the same time? I've read YARN will assign different cores on each different tasks, but in this case, it is a single task And, is it just enough to use multi thread programming in JAVA (hadoop) to use all

QueryPerformanceCounter on multi-core processor under Windows 10 behaves erratically

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Under Windows, my application makes use of QueryPerformanceCounter (and QueryPerformanceFrequency ) to perform "high resolution" timestamping. Since Windows 10 (and only tested on Intel i7 processors so far), we observe erratic behaviours in the values returned by QueryPerformanceCounter . Sometimes, the value returned by the call will jump far ahead and then back to its previous value. It feels as if the thread has moved from one core to another and was returned a different counter value for a lapse of time (no proof, just a gut feeling). This has never been observed under XP or 7 (no data

Assembly and multicore CPUs

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问题 What x86-64 instructions are used to enable/disable other cores/processors and how does one start executing code on them? Is there documentation somewhere on how this is done by the operating system? 回答1: Pretty painful to get an x86 up and going... it is not so much in the cores as in the APIC system. You need to look into the docs for your chipset, tends to be pretty much hidden unfortunately. You will have to be at the kernel level, definitely. Looking at Linux sounds like a good idea. 回答2

Difference between “SOCK”, “PVM”, “MPI”, and “NWS” for the R SNOW package

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问题 The makeCluster function for the SNOW package has the different cluster types of " SOCK ", " PVM ", " MPI ", and " NWS " but I'm not very clear on the differences among them, and more specifically which would be best for my program. Currently I have a queue of tasks of different length going into a load balancing cluster with clusterApplyLB and am using a 64bit 32-core Windows machine. I am looking for a brief description of the differences among the four cluster types, which would be best

Using Multicore in R for a pentium 4 HT machine

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I am using a Pentium 4 HT machine at office for running R, some of the code requires plyr package, which I usually need to wait for 6-7 minutes for the script to finish running, while I saw my processor is only half utilized. I have heard of using Multicore package in R for better utilizing the multicore processor, is my case suitable for this? Thanks! There is a bunch of packages out there to do multicoring. See doMPI , doSNOW , doMC and doSMP . They are all front ends for other programs that run parallelization (like MPI/OpenMPI, multicore package...). On Windows, I've had good experience

c# STILL returning wrong number of cores

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Ok, so I posted in In C# GetEnvironmentVariable("NUMBER_OF_PROCESSORS") returns the wrong number asking about how to get the correct number of cores in C#. Some helpful people directed me to a couple of questions where similar questions were asked but I have already tried those solutions. My question was then closed as being the same as another question, which is true, it is, but the solution given there didn't work. So I'm opening another one hoping that someone may be able to help realising that the other solutions DID NOT work. That question was How to find the Number of CPU Cores via .NET