On Thu, Apr 7, 2016 at 4:19 PM, Jeff Hammond <jeff.scie...@gmail.com> wrote:
> > > On Thu, Apr 7, 2016 at 9:28 AM, Dave Love <d.l...@liverpool.ac.uk> wrote: > >> ... >> Anyhow, the lesson seems to be that you shouldn't use mpi_wtime if you >> need decent precision or realistic mpi_wtick across implementations. >> >> I certainly hope that this isn't the lesson anyone learns from this. It > is extremely important to application developers that MPI_Wtime represent a > "best effort" implementation on every platform. > +1 > Other implementations of MPI have very accurate counters. > This might be a discutable topic. A quick survey of some of the MPI libraries available on a Linux cluster give the following precision for MPI_Wtime implementation : mpich-3.1.4: wtick = 1.000000e-06 Intel(R) MPI Library 5.1.1 for Linux*: wtick = 1.000000e-06 ompi-1.10.2: wtick = 1.000000e-06 ompi-master: wtick = 1.000000e-09 George. > > Jeff > > -- > Jeff Hammond > jeff.scie...@gmail.com > http://jeffhammond.github.io/ > > _______________________________________________ > users mailing list > us...@open-mpi.org > Subscription: http://www.open-mpi.org/mailman/listinfo.cgi/users > Link to this post: > http://www.open-mpi.org/community/lists/users/2016/04/28906.php >
