Hi, Le lundi 23 mars 2015 à 07:29 -0700, Gregory Farnum a écrit : > On Mon, Mar 23, 2015 at 6:21 AM, Olivier Bonvalet <ceph.list@xxxxxxxxx> wrote: > > Hi, > > > > I'm still trying to find why there is much more write operations on > > filestore since Emperor/Firefly than from Dumpling. > > Do you have any history around this? It doesn't sound familiar, > although I bet it's because of the WBThrottle and flushing changes. I only have history for block device stats and global stats reports by «ceph status». When I have upgrade from Dumpling to Firefly (via Emperor), write operations increased a lot on OSD. I suppose it's because of WBThrottle too, but can't find any parameter able to confirm that. > > > > So, I add monitoring of all perf counters values from OSD. > > > > From what I see : «filestore.ops» reports an average of 78 operations > > per seconds. But, block device monitoring reports an average of 113 > > operations per seconds (+45%). > > please thoses 2 graphs : > > - https://daevel.fr/img/firefly/osd-70.filestore-ops.png > > - https://daevel.fr/img/firefly/osd-70.sda-ops.png > > That's unfortunate but perhaps not surprising — any filestore op can > change a backing file (which requires hitting both the file and the > inode: potentially two disk seeks), as well as adding entries to the > leveldb instance. > -Greg > Ok thanks, so this part can be «normal». > > > > Do you see what can explain this difference ? (this OSD use XFS) > > > > Thanks, > > Olivier > > > > _______________________________________________ > > ceph-users mailing list > > ceph-users@xxxxxxxxxxxxxx > > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > -- > 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 > _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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