<html><body class="ApplePlainTextBody" style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">On 2012-11-13, at 4:59 PM, Christopher J. Walker wrote:<br><blockquote type="cite">On 13/11/12 18:49, Richard Henwood wrote:<br></blockquote><blockquote type="cite"><blockquote type="cite">On Tue, Nov 13, 2012 at 12:33 PM, Christopher J. Walker<br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><C.J.Walker@qmul.ac.uk> wrote:<br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">In the Lustre 2.1 manual,<br></blockquote></blockquote></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">http://wiki.whamcloud.com/display/PUB/Documentation<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">has a link titled Lustre Manual 2.1 - though in a row titled 2.x<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">http://git.whamcloud.com/?p=fs/lustre-release.git;a=tree;f=lustre-iokit/mds-survey;hb=HEAD<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">It doesn't seem to work on Lustre 1.8. Should it?<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">No, mds-survey arrived with Lustre 2.2:<br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">http://wiki.whamcloud.com/display/PUB/Lustre+2.2<br></blockquote></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">I was hoping (obviously incorrectly) that whilst it arrived in 2.2, it <br></blockquote><blockquote type="cite">would work with 1.8.<br></blockquote><br>The problem is that the mds-survey tool needs hooks in the Lustre kernel code in order to generate the metadata operations. While this is driven from userspace, the kernel hooks are not in Lustre 1.8.<br><br>Cheers, Andreas<br><br><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">What I'm actually trying to do is migrate an MDS to new hardware - and<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">I'd like to perform some basic tests - partly to see if using LVM has a<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">significant performance impact.<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">mds-survey appeals to me because you don't need any OSTs. I don't know<br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">if a 'OST-free' performance setup is possible for your 1.8 testing -<br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">others may know differently?<br></blockquote></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">That's a clear advantage, and being a standard Lustre tool give some <br></blockquote><blockquote type="cite">confidence too.<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">Chris<br></blockquote><blockquote type="cite">_______________________________________________<br></blockquote><blockquote type="cite">Lustre-discuss mailing list<br></blockquote><blockquote type="cite">Lustre-discuss@lists.lustre.org<br></blockquote><blockquote type="cite">http://lists.lustre.org/mailman/listinfo/lustre-discuss<br></blockquote><br><br>Cheers, Andreas<br>--<br>Andreas Dilger Whamcloud, Inc.<br>Principal Lustre Engineer http://www.whamcloud.com/<br><br><br><br><br></body></html>