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From: Patrick Geoffray (patrick_at_[hidden])
Date: 2007-10-23 12:58:19


Hi Bogdan,

Bogdan Costescu wrote:
> I made some progress: if I configure with "--without-memory-manager"
> (along with all other options that I mentioned before), then it works.
> This was inspired by the fact that the segmentation fault occured in
> ptmalloc2. I have previously tried to remove the MX support without
> any effect; with ptmalloc2 out of the picture I have had test runs
> over MX and TCP without problems.

We have had portability problems using ptmalloc2 in MPICH-GM, specially
relative to threads. In MX, we choose to use dlmalloc instead. It is not
as optimized and its thread-safety has a coarser grain, but it is much
more portable.

Disabling the memory manager in OpenMPI is not a bad thing for MX, as
its own dlmalloc-based registration cache will operate transparently
with MX_RCACHE=1 (default).

Patrick