[mvapich-discuss] mpi_ssend and system call (fortran) conflict

[Dhabaleswar Panda]

Noam,

Section 8.1.2 of MVAPICH2 1.0.3 user guide (a similar section exists for
MVAPICH 1.0.1 too) indicates the following for the use of fork() and
system()  calls.

=================================================================
fork() and system() calls are supported for the OpenFabrics device as long
as the kernel is being used is Linux 2.6.16 or newer. Additionally, the
version of OFED used should be 1.2 or higher. The environment variable
IBV_FORK_SAFE=1 must also be set to enable fork support.
=================================================================

Are all these constraints being satisfied?

Thanks,

DK


On Fri, 18 Jul 2008, Noam Bernstein wrote:

> I've been seeing a problem with mvapich with Intel ifort (10.1.015),
> where a call to system
> will cause subsequent calls to mpi_ssend to hang or crash.  Using
> mpi_send seems to be
> fine, and removing the call to system also fixes the problem.
>
> This is on a dual Opteron, Infiniband system (Mellanox HCAs), with
> OFED 1.2.5.1.  There
> A relaxed error (related to fork) was supposedly fixed in this
> version of  OFED (1.2.1 according
> to the release notes http://www.open-mpi.org/svn/new.php).
>
> mvapich-1.0.1 with make.mvapich.gen2 hangs
>
> mvapich2-1.0.3 with make.mvapich2.ofa crashes, with the message:
>
>    send desc error
>    [0] Abort: [] Got completion with error 1, vendor code=69, dest
> rank=1
>     at line 519 in file ibv_channel_manager.c
>
> (rank 0 is the sender).
>
> I'm starting with this list, since the fact that mpi_ssend has
> problems but
> mpi_send does not makes me think that it's either an mvapich problem or
> an mvapich specific interaction with OFED.
>
> 													thanks,
> 													Noam
>
>