[mpich-discuss] MPI_Allgatherv complexity
balaji at mcs.anl.gov
Mon Nov 2 18:37:33 CST 2009
On 11/02/2009 06:27 PM, Justin Luitjens wrote:
> Actually I just realized I was wrong with what I said. Our code has a
> lot of variation but the allgather test that I wrote and timed in the
> graph I attached will only have a single element of variation between
> each process. Is there an environment variable I can set to force
> either the ring algorithm or the recursive doubling algorithm to compare
> the times?
No, there's no such provisioning (though we should probably add it).
This does look like a performance issue. Can you create a ticket here:
More information about the mpich-discuss