Pardiso only uses 2 cpu cores out of 4

[S__MPay]

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?

[TimP · Accepted solution]

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.