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<p class="MsoNormal"><span style="color:#1F497D">Will MPI_IProbe going to work here? I don’t want to block my thread on a receive. The client can be busy arbitrary amount of time and the server-thread can not be blocked on a receive.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Thanks,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Hirak<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> Roy, Hirak
<br>
<b>Sent:</b> Tuesday, October 21, 2014 9:37 AM<br>
<b>To:</b> discuss@mpich.org<br>
<b>Subject:</b> Re : MPI process killed and SIGUSR1 <o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<pre><span style="font-family:"Calibri","sans-serif";color:black">Hi Wesley,<o:p></o:p></span></pre>
<pre><span style="font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></pre>
<pre><span style="font-family:"Calibri","sans-serif";color:black">So if I do the following from the server side : <o:p></o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black">MPI_Irecv (&buf, 1, MPI_INT, 0, MPI_TAG_SANITY, clientCom, &req);<o:p></o:p></span></pre>
<pre><span style="color:black">MPI_Wait(&req, &stat);<o:p></o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="font-family:"Calibri","sans-serif";color:black">Now the client is killed. However, the wait does not terminate.<o:p></o:p></span></pre>
<pre><span style="color:black"><br></span><span style="font-family:"Calibri","sans-serif";color:black">Thanks,<o:p></o:p></span></pre>
<pre><span style="font-family:"Calibri","sans-serif";color:black">Hirak<o:p></o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
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<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black">It's not guaranteed that you will receive an error from a send (of any kind other than ssend). The reason is that the implementation can buffer the message internally and return to the application before the message is actually transferred. You will definitely receive an error related to any kind of receive, but sends are less reliable in that sense.<o:p></o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black">Thanks,<o:p></o:p></span></pre>
<pre><span style="color:black">Wesley<o:p></o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black">On Oct 20, 2014, at 7:53 AM, Roy, Hirak <<a href="https://lists.mpich.org/mailman/listinfo/discuss">Hirak_Roy at mentor.com</a><mailto:<a href="https://lists.mpich.org/mailman/listinfo/discuss">Hirak_Roy at mentor.com</a>>> wrote:<o:p></o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black">Hi Wesley,<o:p></o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black">Suppose my server-client connection is setup using MPI_Comm_accept/MPI_Comm_connect.<o:p></o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black">Now one of the clients dies.<o:p></o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black">If the server sends a non-blocking message to the dead client by MPI_Isend, will MPI_Wait guaranteed to return Error code?<o:p></o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black">Thanks,<o:p></o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black">Hirak<o:p></o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black">><i>You will only receive the notification if you use a communicating call. That call doesn't do any communication so it won't return the error.<o:p></o:p></i></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<p class="MsoNormal"><o:p> </o:p></p>
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