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Subject: [OMPI users] --bynode vs --byslot
From: Cally K (kalpana0611_at_[hidden])
Date: 2008-05-23 21:07:25


Hi, I have a question about --bynode and --byslot that i would like to
clarify

Say, for example, I have a hostfile

#Hostfile

__________________________
node0
node1 slots=2 max_slots=2
node2 slots=2 max_slots=2
node3 slots=4 max_slots=4
___________________________

There are 4 nodes and 9 slots, how do I run my mpirun, for now I use

a) mpirun -np --bynode 4 ./abcd

I know that the slot thingy is for SMPs, and I have tried running mpirun -np
--byslot 9 ./abcd

and I noticed that its longer when I do --byslot when compared to --bynode

and I just read the faq that said, by defauly the byslot option is used, so
I dun have to use it rite,,,

I am testing my application's performance, need to do some
benchmarking...amd I doing it right by using the bynode option Or I dun mind
benchmarking the byslot option, but only if I am doing it rite.... Could
someone tell me