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<blockquote type=cite class=cite cite=""><font face="Calibri">Can someone
think of a reason to have the library do this over the app ? I can
see that letting the library do this will avoid potential race conditions
that could arise if we let the app do this - basically out of band with
respect to the expected communications traffic.<br>
</font></blockquote>The application can implement this functionality by
having somebody write the appropriate notification protocol as a PMPI
layer and just plugging it in between the application and MPI. If we have
piggybacking, this layer will also be fairly efficient. The only issue
may be that piggybacking over collectives is hard to define, putting a
limit on how efficient such application-level protocols will be. However,
the fact is that different people will want MPI to provide many more
services and protocols than MPI vendors can actually implement. As such,
we're much better off putting together a robust and efficient
piggybacking API than asking for more services to be implemented on top
of the library.<br>
<x-sigsep><p></x-sigsep>
Greg Bronevetsky<br>
Post-Doctoral Researcher<br>
1028 Building 451<br>
Lawrence Livermore National Lab<br>
(925) 424-5756<br>
bronevetsky1@llnl.gov</body>
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