Re: work-load imbalance

From: Daniel Pfenniger <daniel.pfenniger_at_obs.unige.ch>
Date: Thu, 02 Nov 2006 18:26:08 +0100

You don't say how many processes you have used. Maybe you should
try running 1, 2, ...8 processes for a few time-steps and see the
optimal number. Cheers, Dan

Pedro Colin wrote:
> Hi,
>
> Does anyone have a sort of recipe to optimize the work load balance and
> thus to improve the multi-cpu computer performance? I just got a quad with
> double core opteron 64bits proccesors at 2.0 Ghz, so 8 procs in total.
> When I compare the wall time of this computer with a dual opteron at 2.4
> Ghz (single core) in a Gadget2 simulation (N-body only) I only get a
> factor of 2 gain. When I look at the timings.txt I see that this is due to
> work-load imbalance. The procs in the quad run on average twice slower
> than those in the dual. I have made some changes to *BufferSize* and
> *PartAllocFactor* and have got some improvement but still I think I am not
> getting the most of it.
>
> Cheers,
>
> Pedro
Received on 2006-11-02 21:26:49