Intel® oneAPI Math Kernel Library
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Pardiso only uses 2 cpu cores out of 4

S__MPay
Beginner
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I am running a Pardiso solver but it only uses two cores out of 4 cores.

I read the documentations but I cannot find any solution.

I set windows environmental variables MKL_NUM_THREADS = 4 and OMP_NUM_THREADS = 4 but still number of OpenMP threads is 2.

I would appreciate if you could give me some hint on how to solve this problem?

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1 Solution
TimP
Black Belt
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You could look up your CPU at ark.intel.com (if it is an Intel CPU) to be certain that there are 4 cores.  If it is a 2-core CPU with HyperThreading, like the one I am using, the behavior you describe is the normal default, as using 4 threads is expected to be slower than 1 thread pinned to each core while taking advantage of your simd architecture.  If you wish to check it, read up on MKL_DYNAMIC setting.

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TimP
Black Belt
133 Views

You could look up your CPU at ark.intel.com (if it is an Intel CPU) to be certain that there are 4 cores.  If it is a 2-core CPU with HyperThreading, like the one I am using, the behavior you describe is the normal default, as using 4 threads is expected to be slower than 1 thread pinned to each core while taking advantage of your simd architecture.  If you wish to check it, read up on MKL_DYNAMIC setting.

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