Hi, For those who are familiar with OpenMP, I want to assign each of my OpenMP threads to a physical core and I have found that it can be achieved by using the ``GOMP_CPU_AFFINITY`` environment variable. In its documentation (https://gcc.gnu.org/onlinedocs/libgomp/GOMP_005fCPU_005fAFFINITY.html) it uses words like "Binds threads to specific CPUs". I am just wondering what does it mean by CPU here? A physical core? A real CPU? A logical core? Say if I run my program using something like this: "GOMP_CPU_AFFINITY="0 1 2 3" ./bin/mp.bin", and I am allocating three threads inside the program, and I am on a 16 core machine, does this gurante that my threads will be allocated to Core 0 1 2? Thanks a lot. Best, Bob ===================================================== Bob Fang MPhill Advanced Computer Science Student at Computer Lab, University of Cambridge. Contact Address: Churchill College, Cambridge. CB3 0DS