[Starpu-devel] OpenMP StarPU

[Roberto Ribeiro <rbrt.ribeiro@gmail.com>]

Hi,

i'm looking for an aternative way to use OpenMP with StarPU without parallel tasks feature. My first approach is to init the system with a single CPU (conf.ncpus = 1) and inside the codelet func use #pragma omp parallel for.

However, for some unknown reason the threads are instanced but they stall and the kernel remains sequential. Are you aware of anything that may cause this? I've tested without StarPU and the openmp works fine.


One more thing, in your handbook you say:

> The solution is then to use only one combined worker at a time. This can be done by setting single_combined_worker to 1 in the starpu_conf structure, or setting the STARPU_SINGLE_COMBINED_WORKER environment variable to 1. StarPU will then run only one parallel task at a time.

Does this mean that we can't have a GPU worker running concurrently and executing tasks with the same starpu_codelet? For instance, can we schedule a GEMM in a CPU+GPU system using any CPU BLAS implementation and cuBLAS?

Thank you for your time,

Regards

Roberto Ribeiro