On Mar 06, 2009 09:37 -0800, Evan Felix wrote: > Sebastion, you are correct on the OST Memory, you probably wont need the > 16GB, and if you can save money on using only 4GB, and buy bigger/more > drives, you will probably be better off.
In the 1.8 release the OSS nodes will cache reads with little/no performance impact even if your app doesn't use them, but of course performance improvement if you app DOES re-read files commonly, so that should be taken into account. > On 3/5/09 6:29 PM, "Sebastian Gutierrez" > <[email protected]> wrote: > > > Hello > > > > I am looking for advice or suggestions on specking the MDS and OSS for a > > new file system I am building. > > > > The IO patterns as have been explained to me are jobs that either create a > > big mpeg file or thousands of about 100kb frames for video. > > This could grow to hudreds of thousands of 100k files. > > > > I have specked > > 2 MDS for a cluster > > 8x300GB SAS 15k drives for the MDT in a raid 10(I used raid 10 to reduce > > the chance of the MDT becomming a bottleneck with many small files) > > 2x300GB SAS 15k drives for the MGS in a raid 1 The MGS needs virtually no disk IO, so using smallest/cheapest SATA drives is fine. > > 4 OSS servers > > 16GB 667mhz ram > > 2.5 ghz dual quad core procs > > 6x1TB SATA 3 7.2k disks 5TB OST in a raid 5 (possibly running software raid) > > expandable to 2 5TB OSTs Per OSS > > 1xHotspare > > > > Since this is the first Lustre file system I am building. I noticed the > > sizing page: > > http://manual.lustre.org/manual/LustreManual16_HTML/SystemLimits.html#50548887 > > _46859 > > > > The document mentions only dual core procs in regards to the MDS. That's because this section is old. If you want more MDS performance (up to a limit) adding more cores + RAM is useful. > > The document also mentions a much lower amount of system RAM required for > > the OST. > > > > Am I wasting resources here by over-specking these boxes or is it a good > > idea to over spec a bit? > > > > Am I on the right track based on the IO pattern as I understand it? > > > > Sebastian > > > > _______________________________________________ > > Lustre-discuss mailing list > > [email protected] > > http://lists.lustre.org/mailman/listinfo/lustre-discuss > > _______________________________________________ > Lustre-discuss mailing list > [email protected] > http://lists.lustre.org/mailman/listinfo/lustre-discuss Cheers, Andreas -- Andreas Dilger Sr. Staff Engineer, Lustre Group Sun Microsystems of Canada, Inc. _______________________________________________ Lustre-discuss mailing list [email protected] http://lists.lustre.org/mailman/listinfo/lustre-discuss
