[gmx-developers] Timing

Roland Schulz roland at utk.edu
Mon Jan 19 00:16:02 CET 2009


Is there a good reason to summing the time on all cores, when print the
timing (function wallcycle_sum)? In case there is a load imbalance the
maximum norm (multiplied with the number of cores) gives a much more
reasonable time, because the other cores will wait adding practially to the
time. In case their is no load imbalance changing the norm gives the same

I noticed that in the case where a significant amount of time is spent in
write_traj. Then the printed time is still very small, because only one core
(rank=0) is spending time so that the sum is not much affected (for many

BTW: what is GMX_CYCLE_ALL doing?


ORNL/UT Center for Molecular Biophysics cmb.ornl.gov
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://maillist.sys.kth.se/pipermail/gromacs.org_gmx-developers/attachments/20090118/3bf1233e/attachment.html>

More information about the gromacs.org_gmx-developers mailing list