On Mon, 2009-10-26 at 16:21 -0400, Jeff Squyres wrote:
> there's a tiny/
> small amount of overhead inserted by OMPI telling Valgrind "this
> memory region is ok", but we live in an intensely competitive HPC
> environment.
I may be wrong but I seem to remember Julian saying the overhead is
Jeff Squyres wrote:
> Verbs and Open MPI don't have these options on by default because a)
> you need to compile against Valgrind's header files to get them to
> work, and b) there's a tiny/small amount of overhead inserted by OMPI
> telling Valgrind "this memory region is ok", but we live in an
There's a whole class of valgrind warnings that are generated when you
use OS-bypass networks like OpenFabrics. The verbs library and Open
MPI can be configured and compiled with additional instructions that
tell Valgrind where the "problematic" spots are, and that the memory
is actually
Samuel K. Gutierrez wrote:
> Hi Jed,
>
> I'm not sure if this will help, but it's worth a try. Turn off OMPI's
> memory wrapper and see what happens.
>
> c-like shell
> setenv OMPI_MCA_memory_ptmalloc2_disable 1
>
> bash-like shell
> export OMPI_MCA_memory_ptmalloc2_disable=1
>
> Also add the
Hi Jed,
I'm not sure if this will help, but it's worth a try. Turn off OMPI's
memory wrapper and see what happens.
c-like shell
setenv OMPI_MCA_memory_ptmalloc2_disable 1
bash-like shell
export OMPI_MCA_memory_ptmalloc2_disable=1
Also add the following MCA parameter to you run command.
Jeff Squyres wrote:
> Using --enable-debug adds in a whole pile of developer-level run-time
> checking and whatnot. You probably don't want that on production runs.
I have found that --enable-debug --enable-memchecker actually produces
more valgrind noise than leaving them off. Are there
On Oct 26, 2009, at 3:29 PM, Jeff Squyres wrote:
On Oct 26, 2009, at 3:23 PM, Brock Palen wrote:
Is there a large overhead for
--enable-debug --enable-memchecker?
--enable-debug, yes, there is a pretty large penalty. --enable-
debug is really only intended for Open MPI developers. If
