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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 have an application which is mostly using master-slave kind of architecture. One master and <n> number of slaves. The slaves do not communicate between themselves and only sends/receives messages to/from master.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have two ways I can setup the application<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">1><span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>Static : Master and slaves are all in the same MPI World<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">2><span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>Dynamic : Each slave is connected to master using a MPI_Comm and the communicator is created using MPI_Comm_connect/MPI_Comm_accept. Essentially master has <n> communicators.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The way master works is : it uses MPI_WaitAny kind of method to check messages from slave.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Could you please tell me whether <2> can be significantly slow with respect to <1> if all the slaves send lots of small messages?<o:p></o:p></p>
<p class="MsoNormal">Is there some kind of buffering overhead in <2> for <n> communicators and which can be solved using some configuration.<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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