<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>
<body style="overflow-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;">
<div>Can you run command "ncoffsets -sg file.nc" that shows the sizes of file header</div>
<div>and all variables? For the cesm case, is _enddef called only once?</div>
<div><br>
</div>
<div>Could you also point me to the program files that call PnetCDF APIs, including</div>
<div>writing attributes and variables?</div>
<div><br>
</div>
<div><br>
</div>
<div>
<div>Wei-keng </div>
<div><br>
<blockquote type="cite">
<div>On Aug 4, 2023, at 11:05 AM, Jim Edwards <jedwards@ucar.edu> wrote:</div>
<br class="Apple-interchange-newline">
<div>
<div dir="ltr">
<div class="gmail_default" style="font-family:comic sans ms,sans-serif;color:#38761d">
I am using the new ncar system, <a href="https://urldefense.com/v3/__https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwigtcytrsOAAxWXHjQIHVoDD6YQFnoECBcQAQ&url=https*3A*2F*2Farc.ucar.edu*2Fknowledge_base*2F74317833&usg=AOvVaw2aXlWuOfLnua7fFmIgvfoV&opi=89978449__;JSUlJSU!!Dq0X2DkFhyF93HkjWTBQKhk!Xq6u5krREolkIRHG8AL2taDCmg6HsEdgcEoviUVyzqUINi-ipPM1EhtMcJkQfUYghDhutn7DfH5Wjm57wJ9lQhc$" target="_blank">
derecho</a>, which has a lustre parallel file system.</div>
<div class="gmail_default" style="font-family:comic sans ms,sans-serif;color:#38761d">
<br>
</div>
<div class="gmail_default" style="font-family:comic sans ms,sans-serif;color:#38761d">
Looking at the difference between the two headers below makes me wonder if the issue is with variable attributes?<br>
</div>
<div class="gmail_default" style="font-family:comic sans ms,sans-serif;color:#38761d">
<br>
</div>
</div>
</div>
</blockquote>
<div><br>
</div>
snip</div>
<div><br>
<blockquote type="cite">
<div><br>
<div class="gmail_quote">
<div dir="ltr" class="gmail_attr">On Fri, Aug 4, 2023 at 9:39 AM Wei-Keng Liao <<a href="mailto:wkliao@northwestern.edu" target="_blank">wkliao@northwestern.edu</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">
<div>Hi, Jim
<div><br>
</div>
<div>Can your provide the test program and the file header dumped by "ncdump -h", if that is available?</div>
<div>Also, what machine was used in the tests and its the parallel file system configuration is?</div>
<div>These can help diagnose.</div>
<div><br>
</div>
<div>
<div>Wei-keng </div>
<div><br>
<blockquote type="cite">
<div>On Aug 4, 2023, at 8:49 AM, Jim Edwards <<a href="mailto:jedwards@ucar.edu" target="_blank">jedwards@ucar.edu</a>> wrote:</div>
<br>
<div>
<div dir="ltr">
<div class="gmail_default" style="font-family:comic sans ms,sans-serif;color:rgb(56,118,29)">
I am using ncmpi_iput_varn and ncmpi_wait_all to write output from my model. I have a test program that does nothing but test the
<br>
</div>
<div class="gmail_default" style="font-family:comic sans ms,sans-serif;color:rgb(56,118,29)">
performance of the write operation. Attached is a plot of performance in the model and in the standalone application. I'm looking for
<br>
</div>
<div class="gmail_default" style="font-family:comic sans ms,sans-serif;color:rgb(56,118,29)">
clues as to why the model performance is scaling so badly with the number of variables but the standalone program performance is fine.
<br>
</div>
<div class="gmail_default" style="font-family:comic sans ms,sans-serif;color:rgb(56,118,29)">
<br>
</div>
<div class="gmail_default" style="font-family:comic sans ms,sans-serif;color:rgb(56,118,29)">
<br clear="all">
</div>
<br>
<span class="gmail_signature_prefix">-- </span><br>
<div dir="ltr" class="gmail_signature">
<div dir="ltr">
<div>
<div>
<div>Jim Edwards<br>
<br>
</div>
<font size="1">CESM Software Engineer<br>
</font></div>
<font size="1">National Center for Atmospheric Research<br>
</font></div>
<font size="1">Boulder, CO</font> <br>
</div>
</div>
</div>
<span id="m_2599353008599558804m_3752102915513421155m_3416875553179895269m_1419731810550872517m_-4661512969452605678cid:f_lkwn4kse0"><Screenshot 2023-07-27 at 11.49.03 AM.png></span></div>
</blockquote>
</div>
<br>
</div>
</div>
</blockquote>
</div>
<br clear="all">
<br>
<span class="gmail_signature_prefix">-- </span><br>
<div dir="ltr" class="gmail_signature">
<div dir="ltr">
<div>
<div>
<div>Jim Edwards<br>
<br>
</div>
<font size="1">CESM Software Engineer<br>
</font></div>
<font size="1">National Center for Atmospheric Research<br>
</font></div>
<font size="1">Boulder, CO</font> <br>
</div>
</div>
</div>
</blockquote>
</div>
<br>
</div>
</body>
</html>