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I see discussion of this issue here: <br>
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<a href="https://github.com/mpi-forum/mpi-forum-historic/issues/83" id="LPlnk160777">https://github.com/mpi-forum/mpi-forum-historic/issues/83</a><br>
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Puri<br>
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<div id="divRplyFwdMsg" dir="ltr"><font style="font-size: 11pt;" data-ogsc="" face="Calibri, sans-serif" color="#000000"><b>From:</b> mpi-forum <mpi-forum-bounces@lists.mpi-forum.org> on behalf of Balaji, Pavan via mpi-forum <mpi-forum@lists.mpi-forum.org><br>
<b>Sent:</b> Saturday, August 8, 2020 8:51 AM<br>
<b>To:</b> mpi-forum@lists.mpi-forum.org <mpi-forum@lists.mpi-forum.org><br>
<b>Cc:</b> Balaji, Pavan <balaji@anl.gov><br>
<b>Subject:</b> [Mpi-forum] MPI_Request_free restrictions</font>
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<div class="" style="word-wrap:break-word; line-break:after-white-space">Folks,
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<div class="">Does someone remember why we disallowed users from calling MPI_Request_free on nonblocking collective requests?  I remember the reasoning for not allowing cancel (i.e., the operation might have completed on some processes, but not all), but not
 for Request_free.  AFAICT, allowing the users to free the request doesnít make any difference to the MPI library.  The MPI library would simply maintain its own refcount to the request and continue forward till the operation completes.  One of our users would
 like to free NBC requests so they donít have to wait for the operation to complete in some situations.</div>
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<div class="">Unfortunately, when I added the Rput/Rget operations in the RMA chapter, I copy-pasted that text into RMA as well without thinking too hard about it.  My bad!  Either the RMA committee missed it too, or they thought of a reason that I canít think
 of now.</div>
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<div class="">Can someone clarify or remind me what the reason was?</div>
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<div class="">Regards,</div>
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<div class="">  ó Pavan</div>
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<div class="">MPI-3.1 standard, page 197, lines 26-27:</div>
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<div class="">ď<span class="" style="font-size:11pt; font-family:CMR10">It is erroneous to call
</span><span class="" style="font-size:11pt; font-family:CMSS10">MPI</span><span class="" style="font-size:11pt; font-family:CMTT10">_</span><span class="" style="font-size:11pt; font-family:CMSS10">REQUEST</span><span class="" style="font-size:11pt; font-family:CMTT10">_</span><span class="" style="font-size:11pt; font-family:CMSS10">FREE
</span><span class="" style="font-size:11pt; font-family:CMR10">or </span><span class="" style="font-size:11pt; font-family:CMSS10">MPI</span><span class="" style="font-size:11pt; font-family:CMTT10">_</span><span class="" style="font-size:11pt; font-family:CMSS10">CANCEL
</span><span class="" style="font-size:11pt; font-family:CMR10">for a request associated with a nonblocking collective operation.</span>Ē</div>
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