This post was moved here from here: TGV Performance Numbers In the ini file provided, what’s the meaning of parameter gimmik-max-nnz = 512?

It needs to be the path to the shared library (.so or .dylib). If you have a static library it is likely that libxsmm has been compiled incorrectly. Regards, Freddie.

GiMMiK generates C code and just handles the case of sparse operators. libxsmm generates assembly code and handles sparse and dense operators. Its performance is almost always superior as it has complete control over register allocation and things such as unrolling. Regards, Freddie.

However, when I run the case euler_vortex_2d with pyfr1.12.3, with the config setting gimmik = 1(is that means that I am using libxsmm?) it is very slow. [image]

If you are setting gimmik-max-nnz = 1, and -b openmp you will be using libxsmm. On 2D quad cases gimmik can often out perform libxsmm, that is what you are seeing here. Although it does seem to be slower than I would have expected, @fdw is this consistent with your results?

I also use openmp/libxsmm run the TGV case , there is a big efficiency loss of multi-thread parallelism. Here is my machine [5321342971_52141069875_AB6AF20F-BB23-4d87-8A78-578FBAB31E35] And this is expected time [image] [image] [image] Is this OK?

Have a look at some of the discussion in the TGV performance topic as well as other topics. This is fairly common and there are some nuanced reasons for it that are dependent on architecture.

You are running with too many threads for such a small case (or have other OpenMP applications sharing the same cores). For reference with libxsmm on a recent Intel chip: ❯ OMP_NUM_THREADS=2 pyfr run -bopenmp -p euler_vortex_2d.pyfrm euler_vortex_2d.ini 100.0% [====================================…

Although your CPU claims to be a 32-core chip it is actually four eight core chips, and should be treated as such. Hence you will want to run with four MPI ranks with eight threads per rank with everything correctly pinned to the appropriate NUMA zone. The specifics of how to accomplish this depen…

Excuse me, I run the pyfr with mpi, using command like “mpiexec -np 16 pyfr …” [image] It shows this in terminal ,while the process is on ,what’s the problem ?Could you help me ?

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Questions on the TGV case

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