[gmx-users] mdrun load sharing between dual processor machine

Oliver Beckstein oliver at bioch.ox.ac.uk
Thu May 2 13:14:34 CEST 2002

On Thu, 2 May 2002, Lynne E. Bilston wrote:

> Also, does ssh slows down the interconnect compared to rsh?

According to the LAM documentation ssh/rsh is only used to start the
processes on the other nodes; the actual communication is done through lam
and is determined by the -c2c or -lamd options to mpirun (-c2c is supposed
to be faster). The underlying transport mechanism that is determined at
compile time (--with-rpi=tcp|sysv|usysv) might also influence your
performance. usysv seems to be recommended if it works on your system but
I haven't done any proper tests.

[Has anyone looked at the influence of these variables on performance? 
Any recommendations--esp. for clusters of Athlon duals?]


Oliver Beckstein * oliver at bioch.ox.ac.uk

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