[CP2K:3726] hwloc support in cp2k-trunk

Christiane Pousa pousa.ch... at gmail.com
Fri Jan 27 09:31:14 CET 2012


> unlike with binding MPI tasks to "NUMA units",
> i didn't see a significant difference in performance.
>
>
Yes, most part of time the improvements will be around 5-15%. It really
depends on how OS manage processes/threads and how the application itself
was developed.


> yes. updated, compiled and tested. it gives the output that i expect now.
>

good. Libnuma support should now work too.


> We have both. Intel and AMD (which is forcing me to use compiler settings,
> that are compatible with a common subset of both). overall the AMD ones
> benefit the most from using processor and memory affinity, but i was
> surprised
> how much impact it has on the X5677 Intel CPUs (quad-core westmere ep
> with 3.5GHz). just proves that there is always something new to learn...
>

Yes, that is true. On the machines that I have worked, this was a rule too.
Difficult to explain the reasons (cache size, cache.memory protocol??) :)

cheers,
-- 
[]'s
Christiane Pousa Ribeiro

"Judge a man by his questions, rather than by his answers"
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.cp2k.org/archives/cp2k-user/attachments/20120127/fdcf62c3/attachment.html>


More information about the CP2K-user mailing list