On Tue, Apr 07, 2009 at 08:00:39AM -0700, Eugene Loh wrote: > Iain Bason wrote: > > >There are a bunch changes in the shared memory module between 1.2.9 > >and 1.3.1. One significant change is the introduction of the "sendi" > >internal interface. I believe George Bosilca did the initial > >implementation. This is just a wild guess, but maybe there is > >something about sendi that increases latency when using the shared > >memory module. > > But the sm BTL doesn't expose its sendi function, which puts it in the > same camp as most BTLs. > > And the slowdown doesn't seem to be observed by anyone other than Steve > and his colleague?
Is there a debug option that I can try? I've re-installed 1.3.1 several times yesterday using various combination of configure options. There was no change in observed performance. I've tried --disable-smp-locks. I've tried --enable-mpi-threads --with-threads=posix. I've tried --enable-ptmalloc2-internal. I'm willing to try whatever is required to debug this issue. -- Steve
