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<p class="MsoNormal">Hi All,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">We have a parallel program running on a cluster. We recently found a case, which decreases the CPU usage and increase the run-time when increases Nodes. Below is the results table.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The particular run requires a lot of data communication between nodes.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Any thoughts about this phenomena? Or is there any way we can improve the CPU usage when using higher number of nodes?
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">Average CPU Usage (%)<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">Number of Nodes<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">Number of Threads/Node<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">100<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">1<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">8<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">92<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">2<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">8<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">50<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">3<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">8<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">40<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">4<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">8<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">35<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">5<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">8<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">30<o:p></o:p></span></p>
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<td width="119" nowrap="" valign="bottom" style="width:89.0pt;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:15.0pt">
<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">6<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">8<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">25<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">7<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">8<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">20<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">8<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">8<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">20<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">8<o:p></o:p></span></p>
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<p class="MsoNormal" align="center" style="text-align:center"><span style="color:black">4<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks!<o:p></o:p></p>
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