Questions about Threads/core affinity and OpenMp

mcarr18 — Fri, 22 Feb 2019 19:07:31 GMT

I don't understand how we can use these things together :

GOMP_CPU_AFFINITY / KMP_AFFINITY, OMP_PLACES and OMP_PROC_BIND.

In my project, i would like associate core to calculate specifics things. I have a big code with very big arrays (unidimentionnal for 10^6-9 values for each). I have 2 sockets and 28 physics cores (1 node). For some cases, i must use 1-2 big arrays in loops and i think it's intelligent to use 2 sockets for having a big memory cache. And sometimes, One socket could be enough without using QPI which is overhead.

I must have a strategy with openmp's places because it's more simple i think to organize that. Unfortunately, i don't understand the difference between KMP_AFFINITY (if i take the example intel) and OMP_PLACES / OMP_PROC_BIND. I don't know if we can combinate these methods. My feeling is the both do a little the same thing.

Thanks for your future answers

ps : I use fortran language in my code. I have intel compiler and gfortran.

Re: Questions about Threads/core affinity and OpenMp

AlHill — Fri, 22 Feb 2019 19:30:56 GMT

You may get a better answer from the Intel Developer Forum: https://software.intel.com/en-us/forums/intel-visual-fortran-compiler-for-windows

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Re: Questions about Threads/core affinity and OpenMp

mcarr18 — Fri, 22 Feb 2019 21:24:34 GMT

thanks

topic Re: Questions about Threads/core affinity and OpenMp in Mobile and Desktop Processors

Questions about Threads/core affinity and OpenMp

Re: Questions about Threads/core affinity and OpenMp

Re: Questions about Threads/core affinity and OpenMp