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Subject: [OMPI devel] Please provide the pshmem_finalize symbol
From: Bert Wesarg (Bert.Wesarg_at_[hidden])
Date: 2014-05-14 02:19:22


Dear all,

the Score-P community is currently in the process to support the
OpenSHMEM API in its performance measurement infrastructure Score-P [1].
And we are near a release of a new major version of it. Now that Open
MPI also provides an OpenSHMEM implementation, we extended our testing
also to the new 1.8 version of Open MPI. We already submitted some bug
reports while we are working on this, but the last one isn't really a
bug though:

The OpenSHMEM standard does not include the shmem_finalize API, though
Open MPI provides one and also ensures (via the destructor attribute)
that this function is called in the end. But when a performance monitor
like Score-P intercepts the library calls via weak symbols we finally
need to call the original function too. As the user is free to call this
function itself, but Score-P still needs the parallel context to
finalize the measurement after exiting main, we need to intercept
shmem_finalize and call the real shmem_finalize after we are done. But
unfortunately we can't call the original shmem_finalize as there is no
pshmem_finalize in Open MPI. But without finalizing the Open MPI library
orterun will report errors because the application did not call
shmem_finalize.

So our pledge to the Open MPI community is to provide the
pshmem_finalize symbol, even though this function is not (yet) in the
OpenSHMEM standard.

Sincerely,
Bert Wesarg

[1] http://www.vi-hps.org/projects/score-p

-- 
Dipl.-Inf. Bert Wesarg
wiss. Mitarbeiter
Technische Universität Dresden
Zentrum für Informationsdienste und Hochleistungsrechnen (ZIH)
01062 Dresden
Tel.: +49 (351) 463-42451
Fax: +49 (351) 463-37773
E-Mail: Bert.Wesarg_at_tu-dresden.