Storm Zhang wrote:
Here is what I meant: the results of 500 procs in fact shows it with
272-304(<500) real cores, the program's running time is good, which is
almost five times 100 procs' time. So it can be handled very well.
Therefore I guess OpenMPI or Rocks OS does make use of hyperthreading
to do the job. But with 600 procs, the running time is more than
double of that of 500 procs. I don't know why. This is my problem.
BTW, how to use -bind-to-core? I added it as mpirun's options. It
always gives me error " the executable 'bind-to-core' can't be found.
Isn't it like:
mpirun --mca btl_tcp_if_include eth0 -np 600 -bind-to-core scatttest
Thanks for sending the mpirun run and error message. That helps.
It's not recognizing the --bind-to-core option. (Single hyphen, as you
had, should also be okay.) Skimming through the e-mail, it looks like
you are using OMPI 1.3.2 and 1.4.2. Did you try --bind-to-core with
both? If I remember my version numbers, --bind-to-core will not be
recognized with 1.3.2, but should be with 1.4.2. Could it be that you
only tried 1.3.2?
Another option is to try "mpirun --help". Make sure that it reports
--bind-to-core.
