I'm not sure I follow -- are you saying that Open MPI is disabling the large
mmap allocations, and we shouldn't?
On Jan 8, 2010, at 9:25 AM, Sylvain Jeaugey wrote:
> On Thu, 7 Jan 2010, Eugene Loh wrote:
>
> > Could someone tell me how these settings are used in OMPI or give any
> > guidance on
Jeff Squyres wrote:
I'm not sure I follow -- are you saying that Open MPI is disabling the large
mmap allocations, and we shouldn't?
Basically the reverse. The default (I think this means Linux, whether
with gcc, gfortran, Sun f90, etc.) is to use mmap to malloc large
allocations. We don
We should absolutely not change this. For simple applications, yes, things
work if large blocks are allocated on the heap. However, ptmalloc (and most
allocators, really), can't rationally cope with repeated allocations and
deallocations of large blocks. It would be *really bad* (as we've see
