can I use both OMP and CUDA?

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1

Hi,

I'm trying to run GPU benchmarks using both OMP and CUDA packages.
I've tried as follows.
Here I want use 1 GPU, 1 MPI process, 4 OMP threads.

$ env OMP_NUM_THREADS=4 mpirun -np 1 ../../src/lmp_hp6 -sf omp -sf cuda -v g 1 -v x 2 -v y 2 -v z 1 -v t 100 < ../GPU/in.rhodo.cuda

But, it looks like that OMP directive is ignored.

I think MPI works well with CUDA.
I could get performance differences.
But, for OMP, changing OMP_NUM_THREADS value doesn't affect the performance at all.
Any idea?

Thanks,
David

2

You can have only one suffix at a time.

3

Then, isn't it possible to use GPU with OMP?
I know using GPU with MPI is possible.

Thank you,
David