Rahul Nabar <rpnabar_at_[hidden]> writes:
> So, how does one go about selecting a good switch? "The most expensive
> the better" is somewhat a unsatisfying option!
Also it's apparently not always right, if I recall correctly, according
to the figures on MPI switch performance in the reports somewhere
under http://www.cse.dl.ac.uk/disco.¹ The benchmark database there may
also be relevant. I think they include OMPI figures, to bring this
vaguely on topic.
If you're concerned about latency -- which you may be for VASP? -- then
the NICs and their settings are more important than the switch.
(Obviously use Open-MX, not TCP, too.) See
<http://www.nw-grid.ac.uk/LivMPI> for figures on the NICs I could test.
I haven't seen better GigE ping-pong results than those, but would be
¹ Not whatever the currently-politically-correct URL is, but it still