MPICH-1.2.5 on Opteron

Jyh-Shyong Ho c00jsh00 at
Wed Nov 26 01:10:57 EST 2003


I wonder if this is the right please to post this question, however,
I'll appreciate if anyone can provide me some suggestion.

We have a 1+4 nodes of dual Opteron cluster running SuSE Linux
Enterprise 8 for AMD64, I installed MPICH-1.2.5 with PGI 5.1
64-bit compiler on the system. the MPICH configure file
/opt/mpich/ch_p4/share/machines.LINUX has the following lines:


When we ran a MPI program, it did not run with 10 cpus, however,
it ran with 8 cpus. What might be the possible reason that not
all cpus can be used?

Jyh-Shyong Ho, PhD.
Research Scientist
National Center for High-Performance Computing
Hsinchu, Taiwan, ROC
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