Posted by Ignacio on April 08, 2008 at 17:17:55:
Hi all,
I've successfully compiled Molcas 6.4 with mpi (openmpi) in an 8-core 64bit intel computer, and most tests run fine. However, I don't seem to get any performance increase when using CPUS > 1, "molcas verify performance" takes the same real time (or more) with CPUS=2 or CPUS=4 as with CPUS=1. I can see several processes running, one on each core, so the programs are actually running in parallel, but nothing is gained.
Is this normal, can anyone give me a hint of what the problem may be? I have another program (moldy) running fine in parallel with mpi in the same computer, so at least this part is working.
Thanks