Re: [OMPI devel] kernel 2.6.23 vs 2.6.24 - communication/wait times

2010-04-11 Thread Chris Samuel
On 10/04/10 06:59, Oliver Geisler wrote: This is the results of skampi pt2pt, first with shared memory allowed, second shared memory excluded. For what it's worth I can't replicate those results on an AMD Shanghai cluster running a 2.6.32 kernel and Open-MPI 1.4.1. Here is what I see (run und

Re: [OMPI devel] kernel 2.6.23 vs 2.6.24 - communication/wait times

2010-04-11 Thread Chris Samuel
On 10/04/10 15:12, Bogdan Costescu wrote: Have there been any process scheduler changes in the newer kernels ? Are there ever kernels where that doesn't get tweaked ? ;-) I'm not sure that they could explain four orders of magnitude differences though... One idea that comes to mind would b