Cool, I look forward to reading it! -- Regards, Sébastien Han. On Thu, Jan 17, 2013 at 5:29 PM, Mark Nelson <mark.nelson@xxxxxxxxxxx> wrote: > On 01/17/2013 10:24 AM, Sébastien Han wrote: >> >> Hi Stephan, >> >>> - Increase the osdmax value >> >> >> Well actually this doesn't seem to be necessary because when you issue >> a "ceph osd create" the osdmax value is automatically incremented. It >> just that a while ago I saw on the ML or IRC that it was a good >> practice to do this. And this documentation >> http://ceph.com/docs/master/rados/operations/control/ says: >> >> "Set the max_osd parameter in the osd map. This is necessary when >> expanding the storage cluster." >> >> Maybe the doc is outdated on this option, I don't know. >> >>> - Set “filestore flusher” option to false, in your [osd] section >> >> >> During my benchmarks sessions I noticed that disabling this option >> brought way better performance, at least for old hardware. Fo recent >> hardware I haven't seen any difference, but I kept the habit to >> disable it. There are some discussions about this option on the ML. As >> far as I can remember, it's harmless to disable it. >> From the doc here >> http://ceph.com/docs/master/rados/configuration/filestore-config-ref/: > > > I actually have been doing parametric sweeps over the various ceph tunables > to try to see what affects performance. I'll have an article coming out > soonish documenting some of the findings. Typically disabling the flusher > seems to be beneficial on XFS and BTRFS, but it seems to be the opposite on > EXT4. > > >> >> "The filestore flusher forces data from large writes to be written out >> using sync file range before the sync in order to (hopefully) reduce >> the cost of the eventual sync. In practice, disabling ‘filestore >> flusher’ seems to improve performance in some cases." >> >> Cheers, >> >> -- >> Regards, >> Sébastien Han. >> >> >> On Wed, Jan 16, 2013 at 7:41 PM, Stefan Priebe <s.priebe@xxxxxxxxxxxx> >> wrote: >>> >>> >>> Hello Sebastien, >>> hello list, >>> >>> first nice article sebastien ;-) thanks for contributing. >>> >>> I've two question regarding the tips: >>> >>> Can somebody explain me why i should do this?: >>> - Increase the osdmax value >>> - Set “filestore flusher” option to false, in your [osd] section >>> >>> Greets, >>> Stefan >>> -- >>> To unsubscribe from this list: send the line "unsubscribe ceph-devel" in >>> the body of a message to majordomo@xxxxxxxxxxxxxxx >>> More majordomo info at http://vger.kernel.org/majordomo-info.html >> >> -- >> To unsubscribe from this list: send the line "unsubscribe ceph-devel" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
