So then are you planning to re-engineer PetscLayout? Or is it acceptable to have a few PetscLayouts, in their current form, lying around?
On Thu, Nov 24, 2011 at 6:14 PM, Jed Brown <jedbrown at mcs.anl.gov> wrote: > On Thu, Nov 24, 2011 at 18:05, Dmitry Karpeev <karpeev at mcs.anl.gov> wrote: > >> Is O(commSize) storage considered unscalable in this model? > > > I would like to avoid it where possible. If we have million-way > parallelism at the network level (e.g. one million MPI processes), then we > have to justify the memory usage. One 64-bit integer per process is 8MB. If > that is needed once for the entire application, it is probably not an > issue, but if it's needed by every object, then it could add up to a > substantial amount (considering the low-memory estimates). > > The MPICH guys are thinking about this: > > http://www.mcs.anl.gov/~goodell/pdfs/mpi-mem-final.pdf > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-dev/attachments/20111124/a001c7f7/attachment.html>