[Beowulf] Good IB network performance when using 7 cores, poor performance on all 8?

[Chris Samuel]

On Thu, 24 Apr 2014 12:24:23 PM Joe Landman wrote:

> Yeah, that was the other thing I'd forgotten about.  Might want to tweak 
> Cstates to C1.  It could be going over-power and throttling.  Turn of 
> ASPM and other (fairly painful) things.

This Mellanox document has some useful information on that (and other settings
that can affect performance).

http://www.mellanox.com/related-docs/prod_software/Performance_Tuning_Guide_for_Mellanox_Network_Adapters.pdf

cheers,
Chris
-- 
 Christopher Samuel        Senior Systems Administrator
 VLSCI - Victorian Life Sciences Computation Initiative
 Email: samuel at unimelb.edu.au Phone: +61 (0)3 903 55545
 http://www.vlsci.org.au/      http://twitter.com/vlsci