Jeff and I were looking at a similar issue today and suddenly realized that the
mappings were different - i.e., what ranks are on what nodes differs depending
on how you launch. You might want to check if that's the issue here as well.
Just launch the attached program using mpirun vs srun and ch
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On 04/09/13 18:33, George Bosilca wrote:
> You can confirm that the slowdown happen during the MPI
> initialization stages by profiling the application (especially the
> MPI_Init call).
NAMD helpfully prints benchmark and timing numbers during the in
Hi,
I and my colleague found 3 OSC-related bugs in OMPI datatype code.
One for trunk and v1.6/v1.7 branches, and two for only v1.6 branch.
(1) OMPI_DATATYPE_ALIGN_PTR should be placed after memcpy
Last year I reported a bug in OMPI datatype code and it was
fixed in r25721. But the fix was no
On Sep 4, 2013, at 4:33 AM, George Bosilca wrote:
> You can confirm that the slowdown happen during the MPI initialization stages
> by profiling the application (especially the MPI_Init call).
You can also try just launching "MPI hello world" (i.e., examples/hello_c.c).
It just calls MPI_INIT
This is 1.7.3 - there is no comm thread in ORTE in that version.
On Sep 4, 2013, at 1:33 AM, George Bosilca wrote:
> You can confirm that the slowdown happen during the MPI initialization stages
> by profiling the application (especially the MPI_Init call).
>
> Another possible cause of slowdo
OK, I take that back. Based on the MPI standard (age 488) only the thread that
called MPI_Init or MPI_Init_thread must return true in this case. The logic I
was exposing in my previous email is left to the user.
George.
On Sep 4, 2013, at 12:11 , George Bosilca wrote:
> You're in the SERIA
You're in the SERIALIZED mode, so any thread can make MPI calls. As in such
mode there is no notion of thread_main, consistently returning true out of
MPI_Is_thread_main seem like a reasonable approach.
This function will have a different behavior in the FUNNELED mode.
George.
On Sep 4, 2013
I'm using Open MPI 1.6.5 as packaged in Fedora 19. This build does not
enable THREAD_MULTIPLE support:
$ ompi_info | grep Thread
Thread support: posix (MPI_THREAD_MULTIPLE: no, progress: no)
In my code I call MPI_Init_thread(required=MPI_THREAD_MULTIPLE). After
that, MPI_Query_thread()
You can confirm that the slowdown happen during the MPI initialization stages
by profiling the application (especially the MPI_Init call).
Another possible cause of slowdown might be the communication thread in the
ORTE. If it remains active outside the initialization it will definitively
distu
