On Tue, Apr 23, 2013 at 10:17:46AM -0700, Ralph Castain wrote: > > On Apr 23, 2013, at 10:09 AM, Nathan Hjelm <hje...@lanl.gov> wrote: > > > On Tue, Apr 23, 2013 at 12:21:49PM +0400, ???????????????????? ???????????? > > wrote: > >> Hi, > >> > >> Nathan, could you please advise what is expected startup time for OpenMPI > >> job at such scale (128K ranks)? I'm interesting in > >> 1) time from mpirun start to completion of MPI_Init() > > > > It takes less than a minute to run: > > > > mpirun -n 131072 /bin/true > > > > > >> 2) time from MPI_Init() start to completion of MPI_Init() > > > > A simple MPI application took about about 1.25 mins to run. If you want to > > see our setup you can take a look at contrib/platform/lanl/cray_xe6. > > > >>> From my experience for 52800 rank job > >> 1) took around 20 min > >> 2) took around 12 min > >> that actually looks like a hung. > > > > How many nodes? I have never seen launch times that bad on Cielo. You could > > try adding -mca routed debruijn -novm and see if that helps. It will reduce > > the amount of communication between compute nodes and the login node. > > I believe the debrujin module was turned off a while ago due to a bug that > wasn't fixed. However, try using
Was it turned off or was the priority lowered? If it was lowered then -mca routed debruijn should work. The -novm is to avoid the bug (as I understand it). I am working on fixing the bug now in hope it will be ready for 1.7.2. -Nathan
