<div dir="ltr">Dear Stefan,<div><br></div><div>Sorry, I didn't make myself clear. What I meant is whether we can further improve the parallel computing performance, as I am only using about 1/3 of the computing power of each node. Thank you very much!<br></div><div><br></div><div>Best regards,</div><div>Wei XU</div><div><br></div><div><span style="font-size:12.8px">Date: Wed, 07 Dec 2016 12:01:42 +0100</span><br style="font-size:12.8px"><span style="font-size:12.8px">From: </span><a href="mailto:nek5000-users@lists.mcs.anl.gov" style="font-size:12.8px" target="_blank">nek5000-users@lists.mcs.<wbr>anl.gov</a><br style="font-size:12.8px"><span style="font-size:12.8px">To: <</span><a href="mailto:nek5000-users@lists.mcs.anl.gov" style="font-size:12.8px" target="_blank">nek5000-users@lists.mcs.anl.g<wbr>ov</a><span style="font-size:12.8px">></span><br style="font-size:12.8px"><span style="font-size:12.8px">Subject: Re: [Nek5000-users] Parallel speedup on supercomputer</span><br style="font-size:12.8px"><span style="font-size:12.8px">        Tianhe-2</span><br style="font-size:12.8px"><span style="font-size:12.8px">Message-ID:</span><br style="font-size:12.8px"><span style="font-size:12.8px">        <</span><a href="mailto:mailman.7291.1481108507.3602.nek5000-users@lists.mcs.anl.gov" style="font-size:12.8px" target="_blank">mailman.7291.1481108507.3602.<wbr>nek5000-users@lists.mcs.anl.go<wbr>v</a><span style="font-size:12.8px">></span><br style="font-size:12.8px"><span style="font-size:12.8px">Content-Type: text/plain; charset="utf-8"</span><br style="font-size:12.8px"><br style="font-size:12.8px"><span style="font-size:12.8px">Why do think something is wrong i.e. you have a problem?</span><br style="font-size:12.8px"><br style="font-size:12.8px"><span style="font-size:12.8px">From: <</span><a href="mailto:nek5000-users-bounces@lists.mcs.anl.gov" style="font-size:12.8px" target="_blank">nek5000-users-bounces@lists.m<wbr>cs.anl.gov</a><span style="font-size:12.8px">> on behalf of <</span><a href="mailto:nek5000-users@lists.mcs.anl.gov" style="font-size:12.8px" target="_blank">nek5000-users@lists.mcs.anl.g<wbr>ov</a><span style="font-size:12.8px">></span><br style="font-size:12.8px"><span style="font-size:12.8px">Reply-To: <</span><a href="mailto:nek5000-users@lists.mcs.anl.gov" style="font-size:12.8px" target="_blank">nek5000-users@lists.mcs.anl.g<wbr>ov</a><span style="font-size:12.8px">></span><br style="font-size:12.8px"><span style="font-size:12.8px">Date: Wednesday, December 7, 2016 at 10:39 AM</span><br style="font-size:12.8px"><span style="font-size:12.8px">To: <</span><a href="mailto:nek5000-users@lists.mcs.anl.gov" style="font-size:12.8px" target="_blank">nek5000-users@lists.mcs.anl.g<wbr>ov</a><span style="font-size:12.8px">></span><br style="font-size:12.8px"><span style="font-size:12.8px">Subject: Re: [Nek5000-users] Parallel speedup on supercomputer Tianhe-2</span><br style="font-size:12.8px"><br style="font-size:12.8px"><span style="font-size:12.8px">Dear Stefan,</span><br style="font-size:12.8px"><br style="font-size:12.8px"><span style="font-size:12.8px">Thank you very much! Can I do anything on the Nek5000 side to reduce the problem?</span><br style="font-size:12.8px"><br style="font-size:12.8px"><span style="font-size:12.8px">Best regards</span><br style="font-size:12.8px"><span style="font-size:12.8px">Wei XU</span><br style="font-size:12.8px"><br style="font-size:12.8px"><span style="font-size:12.8px">Date: Tue, 6 Dec 2016 16:34:04 +0100</span><br style="font-size:12.8px"><span style="font-size:12.8px">From: </span><a href="mailto:nek5000-users@lists.mcs.anl.gov" style="font-size:12.8px" target="_blank">nek5000-users@lists.mcs.<wbr>anl.gov</a><br style="font-size:12.8px"><span style="font-size:12.8px">To: </span><a href="mailto:nek5000-users@lists.mcs.anl.gov" style="font-size:12.8px" target="_blank">nek5000-users@lists.mcs.<wbr>anl.gov</a><br style="font-size:12.8px"><span style="font-size:12.8px">Subject: Re: [Nek5000-users] Parallel speedup on supercomputer</span><br style="font-size:12.8px"><span style="font-size:12.8px">        Tianhe-2</span><br style="font-size:12.8px"><span style="font-size:12.8px">Message-ID:</span><br style="font-size:12.8px"><span style="font-size:12.8px">        <</span><a href="mailto:mailman.7242.1481038500.3602.nek5000-users@lists.mcs.anl.gov" style="font-size:12.8px" target="_blank">mailman.7242.1481038500.3602.<wbr>nek5000-users@lists.mcs.anl.go<wbr>v</a><span style="font-size:12.8px">></span><br style="font-size:12.8px"><span style="font-size:12.8px">Content-Type: text/plain; charset="us-ascii"</span><br style="font-size:12.8px"><br style="font-size:12.8px"><span style="font-size:12.8px">That'a reasonable. The core compete for shared resources (L3 and DDR).</span><br style="font-size:12.8px"><br style="font-size:12.8px"><span style="font-size:12.8px">______________________________</span><span style="font-size:12.8px"><wbr>_________________ Nek5000-users mailing list </span><a href="mailto:Nek5000-users@lists.mcs.anl.gov" style="font-size:12.8px" target="_blank">Nek5000-users@lists.mcs.<wbr>anl.gov</a><span style="font-size:12.8px"> </span><a href="https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users" rel="noreferrer" style="font-size:12.8px" target="_blank">https://lists.mcs.anl.<wbr>gov/mailman/listinfo/nek5000-<wbr>users</a><br style="font-size:12.8px"><br style="font-size:12.8px"><span style="font-size:12.8px">-------------- next part --------------</span><br style="font-size:12.8px"><span style="font-size:12.8px">An HTML attachment was scrubbed...</span><br style="font-size:12.8px"><span style="font-size:12.8px">URL: <</span><a href="http://lists.mcs.anl.gov/pipermail/nek5000-users/attachments/20161207/c5b7a050/attachment-0001.html" rel="noreferrer" style="font-size:12.8px" target="_blank">http://lists.mcs.anl.gov/pipe<wbr>rmail/nek5000-users/attachment<wbr>s/20161207/c5b7a050/attachment<wbr>-0001.html</a><span style="font-size:12.8px">></span><br style="font-size:12.8px"><br style="font-size:12.8px"><span style="font-size:12.8px">------------------------------</span><br></div><div><br></div><div><span style="font-size:12.8px">Date: Tue, 6 Dec 2016 16:25:22 +0800</span><br style="font-size:12.8px"><span style="font-size:12.8px">From: </span><a href="mailto:nek5000-users@lists.mcs.anl.gov" style="font-size:12.8px" target="_blank">nek5000-users@lists.mcs.<wbr>anl.gov</a><br style="font-size:12.8px"><span style="font-size:12.8px">To: </span><a href="mailto:nek5000-users@lists.mcs.anl.gov" style="font-size:12.8px" target="_blank">nek5000-users@lists.mcs.<wbr>anl.gov</a><br style="font-size:12.8px"><span style="font-size:12.8px">Subject: Re: [Nek5000-users] Parallel speedup on supercomputer</span><br style="font-size:12.8px"><span style="font-size:12.8px">        Tianhe-2</span><br style="font-size:12.8px"><span style="font-size:12.8px">Message-ID:</span><br style="font-size:12.8px"><span style="font-size:12.8px">        <</span><a href="mailto:mailman.7221.1481012750.3602.nek5000-users@lists.mcs.anl.gov" style="font-size:12.8px" target="_blank">mailman.7221.1481012750.3602.<wbr>nek5000-users@lists.mcs.anl.go<wbr>v</a><span style="font-size:12.8px">></span><br style="font-size:12.8px"><span style="font-size:12.8px">Content-Type: text/plain; charset="utf-8"</span><br style="font-size:12.8px"><br style="font-size:12.8px"><span style="font-size:12.8px">Dear Stefan,</span><br style="font-size:12.8px"><br style="font-size:12.8px"><span style="font-size:12.8px">Thank you for your reply. There are 139056 elements and the polynomial</span><br style="font-size:12.8px"><span style="font-size:12.8px">order is 7 (lx1=8).  I measure the solver time to compute the speedup. For</span><br style="font-size:12.8px"><span style="font-size:12.8px">example, the serial job takes 2564.59s and the same job with 24 tasks takes</span><br style="font-size:12.8px"><span style="font-size:12.8px">302.18s. The speedup is about 8.5. This is on a single Tianhe-2 node. The</span><br style="font-size:12.8px"><span style="font-size:12.8px">speedup between nodes is quite good.</span><br style="font-size:12.8px"><br style="font-size:12.8px"><span style="font-size:12.8px">I also test the code on my 36-core computer (Dual Xeon E5 18-Core). I can</span><br style="font-size:12.8px"><span style="font-size:12.8px">only get about 12 times speedup when I use 36 tasks. It is also about 1/3.</span><br style="font-size:12.8px"><br style="font-size:12.8px"><span style="font-size:12.8px">Best regards,</span><br style="font-size:12.8px"><span style="font-size:12.8px">Wei XU</span><br></div><div><br></div></div>