<div dir="ltr"><div dir="ltr"><br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Fri, Oct 29, 2021 at 4:40 AM Karthikeyan Chockalingam - STFC UKRI <<a href="mailto:karthikeyan.chockalingam@stfc.ac.uk">karthikeyan.chockalingam@stfc.ac.uk</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
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<p class="MsoNormal">Hello,<u></u><u></u></p>
<p class="MsoNormal"><u></u> <u></u></p>
<p class="MsoNormal">I used the flags <span style="font-size:10.5pt;font-family:"Segoe UI",sans-serif;color:rgb(36,36,36);background:rgb(233,234,246)">-memory_view -malloc_log
</span> to ran a problem on the same size on 32 cores and 64 cores.<u></u><u></u></p>
<p class="MsoNormal"><u></u> <u></u></p>
<p class="MsoNormal">I understand what is total, max and min memory usage of the problem is. </p></div></div></blockquote><div><br></div><div>Total is the sum of all 32/62 processes. Max is, as it says "<span style="background-color:rgb(233,234,246);color:rgb(36,36,36);font-family:"Segoe UI",sans-serif;font-size:14px">Maximum (over computational time)</span>" </div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div lang="EN-GB" style="overflow-wrap: break-word;"><div class="gmail-m_3983646568712557441WordSection1"><p class="MsoNormal">However I don’t understand the difference between Maximum and Current process memory?<u></u><u></u></p>
<p class="MsoNormal"><u></u> </p></div></div></blockquote><div><br></div><div>Current memory usage does not include some earlier high water mark in memory usage.</div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div lang="EN-GB" style="overflow-wrap: break-word;"><div class="gmail-m_3983646568712557441WordSection1"><p class="MsoNormal"><u></u></p>
<p class="MsoNormal">I also curious to understand why the memory usage is different on 32 cores (1 node, 2 sockets with 16 cores/socket) and 64 cores (2 nodes) for a problem of the same size?</p></div></div></blockquote><div><br></div><div>There is some data and metadata that is stored redundantly on each process.</div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div lang="EN-GB" style="overflow-wrap: break-word;"><div class="gmail-m_3983646568712557441WordSection1"><p class="MsoNormal"><span><u></u><u></u></span></p>
<p class="MsoNormal"><u></u> <u></u></p>
<p class="MsoNormal" style="background:rgb(233,234,246)"><span style="font-size:10.5pt;font-family:"Segoe UI",sans-serif;color:rgb(36,36,36)">On 32 core:<u></u><u></u></span></p>
<p class="MsoNormal"><span><u></u> <u></u></span></p>
<p class="MsoNormal" style="background:rgb(233,234,246)"><span style="font-size:10.5pt;font-family:"Segoe UI",sans-serif;color:rgb(36,36,36)">Summary of Memory Usage in PETSc<u></u><u></u></span></p>
<p class="MsoNormal" style="background:rgb(233,234,246)"><span style="font-size:10.5pt;font-family:"Segoe UI",sans-serif;color:rgb(36,36,36)">Maximum (over computational time) process memory: total 7.5014e+10 max 2.6396e+09 min 2.0659e+09<u></u><u></u></span></p>
<p class="MsoNormal" style="background:rgb(233,234,246)"><span style="font-size:10.5pt;font-family:"Segoe UI",sans-serif;color:rgb(36,36,36)">Current process memory: total 3.2583e+10 max 1.3562e+09
min 8.3587e+08<u></u><u></u></span></p>
<p class="MsoNormal"><span><u></u> <u></u></span></p>
<p class="MsoNormal" style="background:rgb(233,234,246)"><span style="font-size:10.5pt;font-family:"Segoe UI",sans-serif;color:rgb(36,36,36)">On 64 core:<u></u><u></u></span></p>
<p class="MsoNormal"><span><u></u> <u></u></span></p>
<p class="MsoNormal" style="background:rgb(233,234,246)"><span style="font-size:10.5pt;font-family:"Segoe UI",sans-serif;color:rgb(36,36,36)">Summary of Memory Usage in PETSc<u></u><u></u></span></p>
<p class="MsoNormal" style="background:rgb(233,234,246)"><span style="font-size:10.5pt;font-family:"Segoe UI",sans-serif;color:rgb(36,36,36)">Maximum (over computational time) process memory: total 7.9337e+10 max 1.5433e+09 min 1.0319e+09<u></u><u></u></span></p>
<p class="MsoNormal" style="background:rgb(233,234,246)"><span style="font-size:10.5pt;font-family:"Segoe UI",sans-serif;color:rgb(36,36,36)">Current process memory: total 6.4491e+10 max 1.2090e+09
min 8.4000e+08<u></u><u></u></span></p>
<p class="MsoNormal"><u></u> <u></u></p>
<p class="MsoNormal">Kind regards,<u></u><u></u></p>
<p class="MsoNormal">Karthik.<u></u><u></u></p>
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