OpenMathLib / OpenMathLib/OpenBLAS

how to use parallel potrf

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Dominant language
C
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Description

I am currently using the develop version of OpenBLAS which was built with simpe make , and I'm trying to utilize the parallel version of the POTRF function. However, I am encountering issues with parallel execution.
Here is the core code.

#include "cblas.h"
#include "lapacke.h"
// ...

info = LAPACKE_spotrf(LAPACK_ROW_MAJOR, 'L', n, A, n);

matrix sizes ranging from 36000 x 36000 to 60000 x 60000 and runs on a 256 core tsv110 architecture machine.
I have set OPENBLAS_NUM_THREADS=20, but when I monitor the process with the top command, I observe that only one core is being utilized.

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Research direction

No source file or test is named. Start at the LAPACKE_spotrf entry point and the simple make build configuration, then check how OPENBLAS_NUM_THREADS affects parallel POTRF on the reported TSV110 setup; document the required configuration and expected threading behavior.

Written by the indexing model from the issue text.

Assessment

Tech stack
c
Domain
hpc, performance
Issue type
Documentation
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
20/100

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