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Questions tagged [affinity]

Anything related to processor affinity, also known as CPU pinning. The processor affinity is a propriety of a process or a thread in an OS on multi-processor or multi-core systems that influences the OS' scheduling algorithm, binding the execution of that process (or thread) to a specific processor (or core). DO NOT use this tag as a synonym for [affinetransform] tag.

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Set CPU Affinity in PHP?

Pretty straightforward question - is there a way to set the CPU affinity via PHP? Any of the following will do: Setting the affinity of the current process via a PHP call. Setting the affinity of a specific PID via a PHP call. As a last resort,…
rinogo
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Code for detecting APIC id returns same ids for different logical processors

I run my NT service on an Intel Core2 based Win2k3 machine where I need to iterate through all logical CPUs (all bits in process affinity). To do so I call GetProcessAffinityMask() to retrieve the system affinity mask and then switch the process to…
sharptooth
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Process affinity in Windows Phone

I WP library project, I am trying to bind the heavy-lifting process to the hardware thread (0 or 1). So the app consuming the library use other available core. Can we set process affinity in Windows Phone 8 app? I cannot find documentation on…
vulcan raven
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Is there a way to set thread affinity to a processor core with the boost thread library?

And would it be a good idea to do so if I needed the processor cores running on 100% for a dozen seconds or would I get better performance if I let the system decide how to handle the threads? What I need is fast execution and I'm worried the system…
Kesarion
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Setting affinity in multicore x86 processors

( I ask because it was before serious SMP and multicore that I studied OS. I like to have some vision of how code is being executed. ) If I have a multicore x86 CPU booting directly into my program. Can someone recommend a website which describes…
BubbaT
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Why would you need to know about each processor in particular?

I'm curious to understand what could be the motivation behind the fine-grained detail of each virtual processor that the Windows 8 task manager seems to be focusing on. Here's a screenshot (from here):                  I know this setup could only…
Camilo Martin
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Get process and thread affinity mask on Linux

On Windows, there exists the GetProcessAffinityMask API call, and there also exists a roundabout way of finding the thread affinity mask, seen here: Query thread (not process) processor affinity? Is there any way of getting this information in…
ahelwer
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setting processor affinity with C++ that will run on Linux

Possible Duplicate: CPU Affinity I'm running on Linux and I want to write a C++ program that will set 2 specific processors that my 2 applications that will run in parallel (i.e. setting each process to run on a different core/CPU). I want to use…
Ifeanyi
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How can I programatically set the affinity of all running processes in WIndows 7?

Is there any way to set the affinity for all running processes in Windows 7? I want to run some hyperthreading benchmarks, and I want to ensure that they're running alone on a certain core. I'm running them with a wrapper, and I want to do…
Nathan Fellman
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How to assign cpu affinity for Python 3 subprocess?

I am very much a novice at Python. I am running a Tkinter GUI on Windows 7 and Windows 10. I have a subprocess running a data logger routine at 1 KHz. I would like to set a cpu affinity for the subprocess, I am building with Python 3.8.
PEJ
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Java: Will a looping Thread.sleep() always run on the same physical core?

I'm trying to understand Java internals about their scheduling and thread affinity. The question is: given an infinite loop, running on a thread as such in a multicore environment (e.g. 8): while(true) Thread.sleep(1000); Will this operation…
M4rk
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Why is an infinite loop sleeping mostly on an isolated core?

I tried the following code to give all execution time by isolating CPU on Centos 8: #include #include #include int main() { volatile uint32_t i = 0; cpu_set_t cpuset; CPU_ZERO(&cpuset); …
avatli
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Using multiple CPU cores in TensorFlow

I have extensively studied other answers on TensorFlow and I just cannot seem to get it to use multiple cores on my CPU. According to htop, the following program only uses a single CPU core: import tensorflow as tf n_cpus = 20 sess =…
Elliott Slaughter
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How to properly use TSX-NI (both HLE and RTM) when threads might switch cores?

It seems that Intel's Transactional Synchronization Extensions (TSX-NI) work on a per-CPU basis. This applies to both the _InterlockedXxx_HLE{Acquire,Release} Hardware Lock Elision functions (HLE), as well as for the _xbegin/_xend/etc. Restricted…
user541686
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How can I set a thread's CPU affinity in Qt5?

Working with threads in Qt5, how can I set a single thread's CPU affinity? I want to specify a mask of available CPU cores that the thread may run under. In other words, what is the Qt5 equivalent to Posix thread's pthread_setaffinity_np() ? Can I…
Mr. Developerdude
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