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Can not use all process cores on one workstation

YaoYe
Novice
1,106 Views

On my workstation there are 128 logic core.  I can monitor them in task manager.  I run mpiexec -n 128 "executable program"

But I  see the OS only use 64 cores and ultility rate about 64% in task manager.  The OS is windows 2016 server 64bit.

Are there some system configuration and options to limit CPU core usage?

Any information from you is helpful for me. Thanks.

 

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GouthamK_Intel
Moderator
1,095 Views

Hi,

Thanks for reaching out to us!

Could you please confirm how you have concluded that only 64 cores are getting utilized out of 128? did you check in the resource monitor?

However, you can check which ranks/processes are mapped to which logical cores in the terminal by setting below the environmental variable.

 

set I_MPI_DEBUG=10

 

Also, please share the terminal output after setting the above variable.

 

Thanks & Regards

Goutham

 

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YaoYe
Novice
1,085 Views

Now the system has NUMA architecture of CPU. Two NUMA node. One node has 64 cores.  when run mpiexec, the os system only use 64 cores in one NUMA node. 

From website, I got SMP, MPP and NUMA are different.

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GouthamK_Intel
Moderator
1,055 Views

Hi,

Could you please provide the output of the below two commands.

  1. cpuinfo
  2. I_MPI_DEBUG=10 mpiexec -n 128 "executable program"


Regards

Goutham


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RahulV_intel
Moderator
1,042 Views

Hi,

 

Just a quick reminder to send the output for the above commands.

 

Thanks,

Rahul

 

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RahulV_intel
Moderator
1,013 Views

Hi,


I have not heard back from you, so I will go ahead and close this thread from my end. Feel free to post a new question, if you still face any issue.


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