"Iliev, Hristo" writes:
> Hi Dave,
>
> Is it MPI_ALLTOALL or MPI_ALLTOALLV that runs slower?
Well, the output says MPI_ALLTOALL, but this prompted me to check, and
it turns out that it's lumping both together.
> If it is the latter,
> the reason could be that the default implementation of MPI_A
alf Of Dave Love
> Sent: Friday, October 18, 2013 6:18 PM
> To: us...@open-mpi.org
> Subject: [OMPI users] debugging performance regressions between versions
>
> I've been testing an application that turns out to be ~30% slower with
OMPI
> 1.6.5 than (the Red Hat packaged ver
I've been testing an application that turns out to be ~30% slower with
OMPI 1.6.5 than (the Red Hat packaged version of) 1.5.4, with the same
mca-params and the same binary, just flipping the runtime. It's running
over openib, and the profile it prints says that alltoall is a factor of
four slower
