Hello! I am new to using CosmoMC and am trying to figure out how to properly parallelize the running of chains. I have a computer with 32 CPUs (16 cores, 2 threads per core) and I am trying to figure out the most efficient way to run 8 chains.
I am running
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nohup mpirun -np 8 ./cosmomc planck_test.ini &
I have set num_threads=2 in the ini file but only 8 processes seem to be running. I figured it would run each chain across 2 threads if num_threads=2.
It also has only been updating chain 0 for a few hours. Output of top command is below:
- Screen Shot 2019-07-24 at 10.06.03 AM.JPG (194.63 KiB) Viewed 5635 times
It doesn't seem to actually be running in parallel and I was hoping someone might help me figure out what I am doing wrong! How should I be setting OMP_NUM_THREADS and num_threads in order to run 8 chains across more than one CPU?
Thanks,
Vivian