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<p class="MsoNormal"><span style="font-family:Palatino">Hi MITgcmers,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:Palatino"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:Palatino">As part of an HPC bid I need to provide some scaling information for MITgcm on their cluster. The test configuration is a reentrant channel 600x800x50 grid points, using just the ocean component and some
idealised forcing fields. As I increased the core count between 48 and 384 the model scaled better than the theoretical scaling (see attached figure). I’m not complaining that it ran faster, but I was surprised. Any thoughts about what would cause this sort
of behaviour? I wondered if it might be something to do with the tiles not fitting in the cache for the low core count simulations. The bid might be more convincing if I can give a plausible explanation for why the model scales better than ideal.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:Palatino"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:Palatino;color:black;mso-fareast-language:EN-GB">Cheers,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:Palatino;color:black;mso-fareast-language:EN-GB">Ed<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:Palatino;color:black;mso-fareast-language:EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black;mso-fareast-language:EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal" align="center" style="text-align:center"><span style="font-family:Palatino;color:black;mso-fareast-language:EN-GB"><img width="1373" height="1" style="width:14.302in;height:.0104in" id="Rectangle_x0020_1" src="cid:image001.png@01D6A171.A7B39970"><o:p></o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:Palatino;color:black;mso-fareast-language:EN-GB">Edward Doddridge</span></b><span style="font-size:10.0pt;font-family:Palatino;color:black;mso-fareast-language:EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><i><span style="font-size:10.0pt;font-family:Palatino;color:black;mso-fareast-language:EN-GB">Research Associate and Theme Leader</span></i><span style="font-size:11.0pt;font-family:Palatino;mso-fareast-language:EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><i><span style="font-size:10.0pt;font-family:Palatino;color:black;mso-fareast-language:EN-GB">Australian Antarctic Program Partnership (AAPP)</span></i><span style="font-size:11.0pt;font-family:Palatino;color:black;mso-fareast-language:EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><i><span style="font-size:10.0pt;font-family:Palatino;color:black;mso-fareast-language:EN-GB">Institute for Marine and Antarctic Studies (IMAS)</span></i><span style="font-size:11.0pt;font-family:Palatino;color:black;mso-fareast-language:EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><i><span style="font-size:10.0pt;font-family:Palatino;color:black;mso-fareast-language:EN-GB">University of Tasmania (UTAS)</span></i><span style="font-size:11.0pt;font-family:Palatino;color:black;mso-fareast-language:EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:Palatino;color:black"><a href="doddridge.me"><span style="color:#0563C1">doddridge.me</span></a></span><o:p></o:p></p>
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