Hints on improving performance with WRF and Pnetcdf

[Rob Latham]

On Sat, Sep 04, 2010 at 09:25:12PM -0500, Gerry Creager wrote:
> Ah, but I'm seeing the same thing on Ranger (UTexas). I'm likely
> going to have to modify the WRF pnetcdf code to identify a
> sufficiently large stripe count (Lustre file system) to see any sort
> of real improvement.

> More to the point, I see worse performance than with normal Lustre
> and regular netcdf. AND, there's no way to set MPI-IO-HINTS in the
> SGE as configured on Ranger. We've tried and their systems folk
> concur, so it's not just me saying it.

I know ranger's running openmpi, but can you give mpich2 a shot?  i
only ask because recent mpich2 releases have an optimized lustre
driver for collective i/o.

==rob

-- 
Rob Latham
Mathematics and Computer Science Division
Argonne National Lab, IL USA