[gmx-developers] MPI slower than Non-MPI gromacs
lindahl at csb.stanford.edu
Wed Feb 18 09:47:25 CET 2004
The Gromacs demo is an extremely small system. Since the innerloops are
coded in assembly it probably needs in the order of a millisecond to do
a step, and your MPI latencies are likely higher than this (or at least
in the same ballpark) if you are using the TCP/IP stack in windows and
Test it with the DPPC membrane system from the benchmark pages at
On Feb 18, 2004, at 3:26 AM, William Bagdan wrote:
> For win32 I have compiled MPICH, FFTW 2.1.5 with MPICH and then
> Gromacs 3.1.4 with MPI and the FFTW with MPI. After Testing the MPICH
> and FFTW with MPI, I then began testing the GMXDemo using MPI. The
> results are not reassuring. With MPI the time is longer than just
> running straight Gromacs without the MPI. Anybody have any ideas? I
> defined USE_MPI, but am not sure if I need to set some other defines
> to get the FFTW.
> If anybody is interested I would be willing to give you the setup for
> compiling everything and the instructions.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Size: 1884 bytes
Desc: not available
More information about the gromacs.org_gmx-developers