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<?xml version="1.0" encoding="UTF-8" standalone="yes"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>LKML: Kevin Puetz: RE: Industry db benchmark result on recent 2.6 kernels</title><link href="/css/message.css" rel="stylesheet" type="text/css" /><link href="/css/wrap.css" rel="alternate stylesheet" type="text/css" title="wrap" /><link href="/css/nowrap.css" rel="stylesheet" type="text/css" title="nowrap" /><link href="/favicon.ico" rel="shortcut icon" /><script src="/js/simple-calendar.js" type="text/javascript"></script><script src="/js/styleswitcher.js" type="text/javascript"></script><link rel="alternate" type="application/rss+xml" title="lkml.org : last 100 messages" href="/rss.php" /><link rel="alternate" type="application/rss+xml" title="lkml.org : last messages by Kevin Puetz" href="/groupie.php?aid=8085" /><script> var _paq = window._paq = window._paq || []; /* tracker methods like "setCustomDimension" should be called before "trackPageView" */ _paq.push(["setDoNotTrack", true]); _paq.push(["disableCookies"]); _paq.push(['trackPageView']); _paq.push(['enableLinkTracking']); (function() { var u="//m.lkml.org/"; _paq.push(['setTrackerUrl', u+'matomo.php']); _paq.push(['setSiteId', '1']); var d=document, g=d.createElement('script'), s=d.getElementsByTagName('script')[0]; g.async=true; g.src=u+'matomo.js'; s.parentNode.insertBefore(g,s); })(); </script></head><body onload="es.jasper.simpleCalendar.init();" itemscope="itemscope" itemtype="http://schema.org/BlogPosting"><table border="0" cellpadding="0" cellspacing="0"><tr><td width="180" align="center"><a href="/"><img style="border:0;width:135px;height:32px" src="/images/toprowlk.gif" alt="lkml.org" /></a></td><td width="32">聽</td><td class="nb"><div><a class="nb" href="/lkml"> [lkml]</a> 聽 <a class="nb" href="/lkml/2005"> [2005]</a> 聽 <a class="nb" href="/lkml/2005/4"> [Apr]</a> 聽 <a class="nb" href="/lkml/2005/4/3"> [3]</a> 聽 <a class="nb" href="/lkml/last100"> [last100]</a> 聽 <a href="/rss.php"><img src="/images/rss-or.gif" border="0" alt="RSS Feed" /></a></div><div>Views: <a href="#" class="nowrap" onclick="setActiveStyleSheet('wrap');return false;">[wrap]</a><a href="#" class="wrap" onclick="setActiveStyleSheet('nowrap');return false;">[no wrap]</a> 聽 <a class="nb" href="/lkml/mheaders/2005/4/3/150" onclick="this.href='/lkml/headers'+'/2005/4/3/150';">[headers]</a>聽 <a href="/lkml/bounce/2005/4/3/150">[forward]</a>聽 </div></td><td width="32">聽</td></tr><tr><td valign="top"><div class="es-jasper-simpleCalendar" baseurl="/lkml/"></div><div class="threadlist">Messages in this thread</div><ul class="threadlist"><li class="root"><a href="/lkml/2005/3/28/161">First message in thread</a></li><li><a href="/lkml/2005/4/1/264">"Chen, Kenneth W"</a><ul><li><a href="/lkml/2005/4/1/268">Linus Torvalds</a><ul><li><a href="/lkml/2005/4/1/327">Nick Piggin</a></li><li class="origin"><a href="">Kevin Puetz</a></li></ul></li><li><a href="/lkml/2005/4/1/320">Paul Jackson</a><ul><li><a href="/lkml/2005/4/1/322">"Chen, Kenneth W"</a><ul><li><a href="/lkml/2005/4/1/331">Paul Jackson</a></li><li><a href="/lkml/2005/4/3/14">David Lang</a><ul><li><a href="/lkml/2005/4/3/17">Andreas Dilger</a></li></ul></li></ul></li></ul></li></ul></li></ul></td><td width="32" rowspan="2" class="c" valign="top"><img src="/images/icornerl.gif" width="32" height="32" alt="/" /></td><td class="c" rowspan="2" valign="top" style="padding-top: 1em"><table><tr><td><table><tr><td class="lp">From</td><td class="rp" itemprop="author">Kevin Puetz <></td></tr><tr><td class="lp">Subject</td><td class="rp" itemprop="name">RE: Industry db benchmark result on recent 2.6 kernels</td></tr><tr><td class="lp">Date</td><td class="rp" itemprop="datePublished">Sun, 03 Apr 2005 20:40:12 -0500</td></tr></table></td><td></td></tr></table><pre itemprop="articleBody">Linus Torvalds wrote:<br /><br />> <br />> <br />> On Fri, 1 Apr 2005, Chen, Kenneth W wrote:<br />>> <br />>> Paul, you definitely want to check this out on your large numa box. I<br />>> booted a kernel with this patch on a 32-way numa box and it took a long<br />>> .... time to produce the cost matrix.<br />> <br />> Is there anything fundamentally wrong with the notion of just initializing<br />> the cost matrix to something that isn't completely wrong at bootup, and<br />> just lettign user space fill it in?<br /><br />Wouldn't getting rescheduled (and thus having another program trash the<br />cache on you) really mess up the data collection though? I suppose by<br />spawning off threads, each with a fixed affinity and SCHED_FIFO one could<br />hang onto the CPU to collect the data. But then it's not (a lot) different<br />than doing it in-kernel.<br /><br />> Then you couple that with a program that can do so automatically (ie<br />> move the in-kernel heuristics into user-land), and something that can<br />> re-load it on demand.<br /><br />This part seems sensible though :-)<br /><br />> Voila - you have something potentially expensive that you run once, and<br />> then you have a matrix that can be edited by the sysadmin later and just<br />> re-loaded at each boot.. That sounds pretty optimal, especially in the<br />> sense that it allows the sysadmin to tweak things depending on the use of<br />> the box is he really wants to.<br />> <br />> Hmm? Or am I just totally on crack?<br />> <br />> Linus<br /><br /><br />-<br />To unsubscribe from this list: send the line "unsubscribe linux-kernel" in<br />the body of a message to majordomo@vger.kernel.org<br />More majordomo info at <a href="http://vger.kernel.org/majordomo-info.html">http://vger.kernel.org/majordomo-info.html</a><br />Please read the FAQ at <a href="http://www.tux.org/lkml/">http://www.tux.org/lkml/</a><br /><br /></pre></td><td width="32" rowspan="2" class="c" valign="top"><img src="/images/icornerr.gif" width="32" height="32" alt="\" /></td></tr><tr><td align="right" valign="bottom"> 聽 </td></tr><tr><td align="right" valign="bottom">聽</td><td class="c" valign="bottom" style="padding-bottom: 0px"><img src="/images/bcornerl.gif" width="32" height="32" alt="\" /></td><td class="c">聽</td><td class="c" valign="bottom" style="padding-bottom: 0px"><img src="/images/bcornerr.gif" width="32" height="32" alt="/" /></td></tr><tr><td align="right" valign="top" colspan="2"> 聽 </td><td class="lm">Last update: 2005-04-06 13:31 聽聽 [from the cache]<br />漏2003-2020 <a href="http://blog.jasper.es/"><span itemprop="editor">Jasper Spaans</span></a>|hosted at <a href="https://www.digitalocean.com/?refcode=9a8e99d24cf9">Digital Ocean</a> and my Meterkast|<a href="http://blog.jasper.es/categories.html#lkml-ref">Read the blog</a></td><td>聽</td></tr></table><script language="javascript" src="/js/styleswitcher.js" type="text/javascript"></script></body></html>