#774: hack to unfix OpenMP threads from cores on Cray machines -----------------------+---------------------------------------------------- Reporter: rhaas | Owner: eschnett Type: task | Status: closed Priority: optional | Milestone: Component: Carpet | Version: Resolution: fixed | Keywords: hack -----------------------+----------------------------------------------------
Comment (by rhaas):
This patch detects faulty assignments when not using -cc numa_node for 2,3 and 12 threads on kraken and does not misdetect 12,6,3,2 threads when using -c numa_node (in the later case the affinity is '''always''' to either cores 0-5 or 6-11).
It way to make it fail would be:
thread 0: affine to core 0,1,2,3,4,5 thread 1: affine to core 0 thread 2: affine to core 0
ie. only thread 0 has its affinity properly set. Kraken does not seem to produce this assignment though (its assignments without -cc numa_node are unusual other, it does spread threads around a bit but seems to always avoid core 1 unless one uses numa_node).
Please apply.