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Physical and Logical Cores: Setting affinities?

  • CPUs
  • Processors
  • Task Manager
Last response: in CPUs
a b à CPUs
August 4, 2010 10:27:28 PM

I am trying to figure out when using two physical cores with two logical HT cores how are they designated in Task Manager (XP)?
They are listed as CPU 0,1,2,3.
If I got it right 0 and 2 are physical processor number one with secondary HT logical processor.
And 1 and 3 are physical processor two with secondary HT logical processor.
I want to make sure this right since I am using FFMpeg to encode using two threads and just want to use one CPU.
I use task manager though I have tried SeeSaw to control affinities also.
Any thoughts would be appreciated

More about : physical logical cores setting affinities

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a c 83 à CPUs
August 5, 2010 1:20:05 AM

From my understanding 1 physical core is just seen as 2 logical cores within windows, it's not 1 physical and 1 logical. Setting affinity, you should see the same performance regardless of what 2 threads you select.
a b à CPUs
August 5, 2010 1:53:30 AM

I have a dual xeon rig where each cpu is has hyperthreading.
So there is two physical cores with two logical.
DVD Flick is mutithreaded when it runs FFMpeg to encode.
So I wanted the two threads the encoder is running to run on one of the
physical processors (1 cpu w/ HT) thereby leaving me the other physical processor to handle other
Basically I want to force the threads to run on one cpu leaving the other one free.
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a b à CPUs
November 16, 2010 2:35:31 PM

Best answer selected by king smp.
a b à CPUs
November 17, 2010 5:28:09 AM

This topic has been closed by Maziar