Hi everyone! I’m new here but I have been using fenics since 2017. Recently I bought a core i9-9900K with 8 cores (16 threads) in order to improve my simulations. I found a very annoying issue that executing the given ft01_poisson.py test problem with UnitSquareMesh(1100, 1100) by python3 ft01_poi…

Hi, Sorry to if you have already fixed this problem and for bringing up this old post, but I was having a similar issue. In my case the high thread usage happens during the dfn.solve call. When you don’t specify a linear solver to use i.e solve(a == L, u, bcs) the solver seems to use as many thr…

I tried the solution in that thread by setting OMP_NUM_THREADS=1 but it didn’t do anything in my case. In my case there is a high thread usage that happens when running in serial. If I don’t specify a linear solver in the dfn.solve call, it uses a large number of threads, but if you specify one i.e…

Setting the OpenMP num threads variable should do the trick, as this is the only parallelization available. Maybe it is overridden later on again? Not sure whether this helps, but the default solver is ‘umfpack’, which is parallel. Another parallel solver is ‘mumps’, so you could try wheter this b…

Oh I see, I thought the default solver was 'petsc' not 'umfpack'. I guess that explains why it was using so many threads. Thanks!

How to set available threads for each resulting job in mpi?

nate October 17, 2019, 3:57pm 3

Have you looked at this thread? Mumps in parallel slower than in serial.

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How to set available threads for each resulting job in mpi?

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