When using Open MPI v1.4.5 I get ~1.1us. That's the same result as I get with Open MPI v1.5.x using mpi_yield_when_idle=0. So I think there is a bug in Open MPI (v1.5.4 and v1.5.5rc2) regarding to the automatic performance mode selection.
When enabling the degraded performance mode for Open MPI 1.4.5 (mpi_yield_when_idle=1) I get ~1.8us latencies. Matthias On Tuesday 28 February 2012 06:20:28 Christopher Samuel wrote: > On 13/02/12 22:11, Matthias Jurenz wrote: > > Do you have any idea? Please help! > > Do you see the same bad latency in the old branch (1.4.5) ? > > cheers, > Chris
