We won't know until 64k and 128k jobs get thru the queue. Will keep u posted. Thanks for your help.
David Trebotich sent from mobile (510) 384-6868 On May 29, 2015 8:32 AM, "Jed Brown" <[email protected]> wrote: > Mark Adams <[email protected]> writes: > > > I don't need your branch because 1) we are not doing any communication in > > this VecAssembly > > There is still synchronization cost in determining that nothing needs to > be done. Moreover, using a size P MPI_Allreduce for that (in > PetscMaxSum) is non-scalable. My branch uses MPI_Reduce_scatter_block > (scalable) when available (MPI-2.2). > > > and I added the IGNORE stuff > > So it takes no time now and everything is groovy? >
