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<p class="MsoNormal">Hi mpich team,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I am using MPICH 3.0.4 sock with dynamic connection (accept/connect).<o:p></o:p></p>
<p class="MsoNormal">I am facing issues with the following scenario, when there is a race condition in MPI_Comm_connect.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Here is the case <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l1 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">1><span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>Server opens a port, writes the port info in a file, calls MPI_Comm_accept<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l1 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">2><span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>Client1 & Client2 reads the port information from file and each client calls MPI_Comm_connect<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l1 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">3><span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>Server accepts one client, disconnects, closes the port, exit<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l1 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">4><span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>One of the client successfully connects, disconnects, exit<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l1 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">5><span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>The other client hangs in MPI_Comm_connect<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">If you do the following steps, you can reproduce the issue<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l0 level1 lfo2"><![if !supportLists]><span style="mso-list:Ignore">1><span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>Please set compiler and installation path of MPICH in makefile<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l0 level1 lfo2"><![if !supportLists]><span style="mso-list:Ignore">2><span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>make : compiles<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l0 level1 lfo2"><![if !supportLists]><span style="mso-list:Ignore">3><span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>make run_bad<o:p></o:p></p>
<p class="MsoListParagraph"><o:p> </o:p></p>
<p class="MsoNormal">I have noticed that in case client calls MPI_Comm_connect after the port is closed, the connect calls successfully terminates with error (make run_good).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Please let me know whether it is a bug or not.<o:p></o:p></p>
<p class="MsoNormal">Please also let me know if the connect call can be configured with a timeout or not.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,<o:p></o:p></p>
<p class="MsoNormal">Hirak<o:p></o:p></p>
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