Gilbert Grosdidier wrote:
I found this parameter mpool_sm_max_size in this post:
But I was unable to spot it back into the 'ompi_info -all'
output for v 1.4.3.
Is it still existing ?
It no longer makes any sense.
If not, which other one is replacing it, please ?
Up through OMPI 1.3.1, OMPI made crude estimates of how large the sm
backing file should be. You could limit the actual size with min and
max parameters. The problem was that the estimate was so crude that
often the allocated size was excessively large while in other cases the
size was insufficient to allow the job to start up. After 1.3.1, the
estimate of the size needed to start the job became much more precise.
So, the job should always at least start. You might still want to
employ a "minimum" (to give the sm area some extra room for performance
reasons), but there is no longer any point in have a "maximum" size.
If you were to set a maximum that is smaller than what OMPI needs, the
job wouldn't start anyhow.
You may find the FAQ useful. Check
http://www.open-mpi.org/faq/?category=sm . There are discussions of
these issues, plus ways of estimating how much room OMPI needs,
therefore also ways of tuning OMPI so that it will need less. E.g., if
you think the sm area is taking up too much space, the FAQ tells you
what parameters to use to make OMPI less space hungry.
Again, check the FAQ.
Also, is it possible to specify to OpenMPI
which filesystem to use for the SM backing file, please ?
Thanks in advance for any help, Regards, G.