From: Latham, Robert J. [mailto:[email protected]] Sent: Friday, April 21, 2017 4:32 PM
good news, maybe?
I can't reproduce this with today's MPICH . I get some debug-logging warnings that you didn't free two of your types, but it doesn't hang on my laptop. Those datatype-related allocations are the only valgrind error I see when I run "mpiexec -np 3 ./mpi-gather 256 256"
That *is* good news. Thanks! The leak is probably because I didn't call MPI_Type_free on the tmp arrays I use to build up the compound types. They are never committed, and it wasn't clear to me if they needed to be freed or not.
Is it possible a 256 by 256 grids could overflow an integer anywhere? I think master has some integer overflow fixes in the gather path that might not have made it into an MPICH release. Aside from that, I'd have to dig through the history to figure out what might be different.
It's tricky to bisect when the error is 'this thing doesn't return at all'! I don't see how that size grid could get in trouble with overflow. It should use (256+4)^2 * 4 * 8 bytes = ~2Mb. The fact that it only shows up with 3 or more ranks suggest that it might be more than just the grid size, but maybe I'm wrong. Now I need to see about getting the Intel MPI fixed... Cheers, Jason _______________________________________________ discuss mailing list [email protected] To manage subscription options or unsubscribe: https://lists.mpich.org/mailman/listinfo/discuss