Hallo, I'm using multi-threading on different machines with 1, 2 or 8 CPUs (deal-version 5.2.0).
If I stop the calculating time for matrix-vector-multiplication with 'vmult' on the different machines with 'clock_t' and 'time_t' , I'll observe that 8 CPUs need a few times as long as 2 CPUs. I have tested it with 196698 dofs. Assembling system-matrix and right-hand-side works fine (stopped with difftime (end, start), all on the same machine): 1 CPU : 63 sec // n_threads = 1; 2 CPUs: 31 sec // n_threads = 2; 4 CPUs: 15 sec // n_threads = 4; 8 CPUs: 9 sec // n_threads = multithread_info.n_default_threads; Is it possible to set the number of threads for 'vmult' too? Or could there be another mistake in my code? Thanks for help, Jörg
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