<div dir="ltr">Hi,<div><br></div><div>In <a href="https://github.com/openstack/nova/blob/master/nova/virt/hardware.py#L396">https://github.com/openstack/nova/blob/master/nova/virt/hardware.py#L396</a> we calculated every possible CPU topologies and sorted by:</div><div><table class="gmail-highlight gmail-tab-size gmail-js-file-line-container" style="box-sizing:border-box;border-collapse:collapse;color:rgb(36,41,46);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji","Segoe UI Symbol";font-size:14px"><tbody style="box-sizing:border-box"><tr style="box-sizing:border-box"><td id="gmail-LC446" class="gmail-blob-code gmail-blob-code-inner gmail-js-file-line" style="box-sizing:border-box;padding:0px 10px;line-height:20px;vertical-align:top;overflow:visible;font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,Courier,monospace;font-size:12px;word-wrap:normal;white-space:pre"> <span class="gmail-pl-c" style="box-sizing:border-box;color:rgb(106,115,125)"><span class="gmail-pl-c" style="box-sizing:border-box">#</span> We want to</span></td></tr><tr style="box-sizing:border-box"><td id="gmail-L447" class="gmail-blob-num gmail-js-line-number" style="box-sizing:border-box;padding:0px 10px;width:50px;min-width:50px;font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,Courier,monospace;font-size:12px;line-height:20px;color:rgba(27,31,35,0.3);text-align:right;white-space:nowrap;vertical-align:top"></td><td id="gmail-LC447" class="gmail-blob-code gmail-blob-code-inner gmail-js-file-line" style="box-sizing:border-box;padding:0px 10px;line-height:20px;vertical-align:top;overflow:visible;font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,Courier,monospace;font-size:12px;word-wrap:normal;white-space:pre"><span class="gmail-pl-c" style="box-sizing:border-box;color:rgb(106,115,125)"><span class="gmail-pl-c" style="box-sizing:border-box">#</span>  - Minimize threads (ie larger sockets * cores is best)</span></td></tr><tr style="box-sizing:border-box"><td id="gmail-L448" class="gmail-blob-num gmail-js-line-number" style="box-sizing:border-box;padding:0px 10px;width:50px;min-width:50px;font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,Courier,monospace;font-size:12px;line-height:20px;color:rgba(27,31,35,0.3);text-align:right;white-space:nowrap;vertical-align:top"></td><td id="gmail-LC448" class="gmail-blob-code gmail-blob-code-inner gmail-js-file-line" style="box-sizing:border-box;padding:0px 10px;line-height:20px;vertical-align:top;overflow:visible;font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,Courier,monospace;font-size:12px;word-wrap:normal;white-space:pre"><span class="gmail-pl-c" style="box-sizing:border-box;color:rgb(106,115,125)"><span class="gmail-pl-c" style="box-sizing:border-box">#</span>  - Prefer sockets over cores</span></td></tr><tr style="box-sizing:border-box"><td id="gmail-L449" class="gmail-blob-num gmail-js-line-number" style="box-sizing:border-box;padding:0px 10px;width:50px;min-width:50px;font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,Courier,monospace;font-size:12px;line-height:20px;color:rgba(27,31,35,0.3);text-align:right;white-space:nowrap;vertical-align:top"></td><td id="gmail-LC449" class="gmail-blob-code gmail-blob-code-inner gmail-js-file-line" style="box-sizing:border-box;padding:0px 10px;line-height:20px;vertical-align:top;overflow:visible;font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,Courier,monospace;font-size:12px;word-wrap:normal;white-space:pre">possible <span class="gmail-pl-k" style="box-sizing:border-box;color:rgb(215,58,73)">=</span> <span class="gmail-pl-c1" style="box-sizing:border-box;color:rgb(0,92,197)">sorted</span>(possible, <span class="gmail-pl-v" style="box-sizing:border-box;color:rgb(227,98,9)">reverse</span><span class="gmail-pl-k" style="box-sizing:border-box;color:rgb(215,58,73)">=</span><span class="gmail-pl-c1" style="box-sizing:border-box;color:rgb(0,92,197)">True</span>,</td></tr><tr style="box-sizing:border-box"><td id="gmail-L450" class="gmail-blob-num gmail-js-line-number" style="box-sizing:border-box;padding:0px 10px;width:50px;min-width:50px;font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,Courier,monospace;font-size:12px;line-height:20px;color:rgba(27,31,35,0.3);text-align:right;white-space:nowrap;vertical-align:top"></td><td id="gmail-LC450" class="gmail-blob-code gmail-blob-code-inner gmail-js-file-line" style="box-sizing:border-box;padding:0px 10px;line-height:20px;vertical-align:top;overflow:visible;font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,Courier,monospace;font-size:12px;word-wrap:normal;white-space:pre"><span class="gmail-pl-v" style="box-sizing:border-box;color:rgb(227,98,9)">key</span><span class="gmail-pl-k" style="box-sizing:border-box;color:rgb(215,58,73)">=</span><span class="gmail-pl-k" style="box-sizing:border-box;color:rgb(215,58,73)">lambda</span> <span class="gmail-pl-smi" style="box-sizing:border-box">x</span>: (x.sockets <span class="gmail-pl-k" style="box-sizing:border-box;color:rgb(215,58,73)">*</span> x.cores,</td></tr><tr style="box-sizing:border-box"><td id="gmail-L451" class="gmail-blob-num gmail-js-line-number" style="box-sizing:border-box;padding:0px 10px;width:50px;min-width:50px;font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,Courier,monospace;font-size:12px;line-height:20px;color:rgba(27,31,35,0.3);text-align:right;white-space:nowrap;vertical-align:top"></td><td id="gmail-LC451" class="gmail-blob-code gmail-blob-code-inner gmail-js-file-line" style="box-sizing:border-box;padding:0px 10px;line-height:20px;vertical-align:top;overflow:visible;font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,Courier,monospace;font-size:12px;word-wrap:normal;white-space:pre">x.sockets,</td></tr><tr style="box-sizing:border-box"><td id="gmail-L452" class="gmail-blob-num gmail-js-line-number" style="box-sizing:border-box;padding:0px 10px;width:50px;min-width:50px;font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,Courier,monospace;font-size:12px;line-height:20px;color:rgba(27,31,35,0.3);text-align:right;white-space:nowrap;vertical-align:top"></td><td id="gmail-LC452" class="gmail-blob-code gmail-blob-code-inner gmail-js-file-line" style="box-sizing:border-box;padding:0px 10px;line-height:20px;vertical-align:top;overflow:visible;font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,Courier,monospace;font-size:12px;word-wrap:normal;white-space:pre">x.threads))

</td></tr></tbody></table></div></div>