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<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt">Hello,</span><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> </span><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt">I have a question regarding the timing of algorithms. I am recording the solving times of SCIP on 100 problems. My end goal is to compare SCIP under different configurations. I am running my experiments
on a dedicated 48-core virtual machine. I have run these problems in two settings:</span><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> </span><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">1. </span><span lang="EN-US" style="font-size:11.0pt">Submit a single job which solves the problems sequentially on a single core. I did not submit any other job, but the machine has regular processes
going on in the background.</span><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">2. </span><span lang="EN-US" style="font-size:11.0pt">Submit 100 jobs and use all cores of the machine. The jobs get assigned to different cores of the machine and run in parallel. </span><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> </span><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt">I use HTCondor for scheduling jobs. I observed that the solving time can go up by up to 70% in case 2 compared to case 1. In addition, running case 1 several times gives very consistent runtimes,
but the runtimes vary a lot more in case 2. </span><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> </span><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt">I was wondering if there are certain measures to take so that timing values are stable (one can guarantee to get the a similar solving time for every run on the same problem) and are short. Even
though the results from case 1 are satisfactory, it is highly time consuming to run all jobs on a single core and keep the remaining 47 cores idle.</span><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> </span><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt">I would be happy to take any suggestions on this matter.</span><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> </span><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt">Thanks.</span><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="TR" style="font-family:"Calibri",sans-serif;color:#333333;mso-ligatures:none">Selin Bayramoglu<o:p></o:p></span></b></p>
<p class="MsoNormal"><span lang="TR" style="font-family:"Calibri",sans-serif;color:#333333;mso-ligatures:none">Ph.D. Student<o:p></o:p></span></p>
<p class="MsoNormal"><b><span style="font-family:"Calibri",sans-serif;color:#333333;mso-ligatures:none">H. Milton Stewart School of Industrial and Systems Engineering</span></b><span style="font-family:"Calibri",sans-serif;color:black;mso-ligatures:none"><br>
</span><span style="font-family:"Calibri",sans-serif;color:#333333;mso-ligatures:none">Georgia Institute of Technology</span><span style="font-family:"Calibri",sans-serif;color:black;mso-ligatures:none"><o:p></o:p></span></p>
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<p class="MsoNormal"><a href="mailto:sbayramoglu3@gatech.edu"><span lang="TR" style="font-family:"Calibri",sans-serif;color:#0563C1;mso-ligatures:none">sbayramoglu3@gatech.edu</span></a></p>
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