I have the journals on a separate disk too. How do you disable the snapshotting on the OSD? Thanks, Erik. On 22-06-15 12:27, Krzysztof Nowicki wrote: > AFAIK the snapshots are useful when the journal sits inside the OSD > filesystem. In case the journal is on a separate filesystem/device then > OSD BTRFS snapshots can be safely disabled. I have done so on my OSDs as > they all use external journals and experienced a reduction in periodic > writes, but they are not completely gone. > > pon., 22.06.2015 o 11:27 użytkownik Jan Schermer <jan@xxxxxxxxxxx > <mailto:jan@xxxxxxxxxxx>> napisał: > > I don’t run Ceph on btrfs, but isn’t this related to the btrfs > snapshotting feature ceph uses to ensure a consistent journal? > > Jan > >> On 19 Jun 2015, at 14:26, Lionel Bouton <lionel+ceph@xxxxxxxxxxx >> <mailto:lionel+ceph@xxxxxxxxxxx>> wrote: >> >> On 06/19/15 13:42, Burkhard Linke wrote: >>> >>> Forget the reply to the list... >>> >>> -------- Forwarded Message -------- >>> Subject: Re: Unexpected disk write activity with >>> btrfs OSDs >>> Date: Fri, 19 Jun 2015 09:06:33 +0200 >>> From: Burkhard Linke >>> <Burkhard.Linke@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> >>> <mailto:Burkhard.Linke@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> >>> To: Lionel Bouton <lionel+ceph@xxxxxxxxxxx> >>> <mailto:lionel+ceph@xxxxxxxxxxx> >>> >>> >>> >>> Hi, >>> >>> On 06/18/2015 11:28 PM, Lionel Bouton wrote: >>> > Hi, >>> *snipsnap* >>> >>> > - Disks with btrfs OSD have a spike of activity every 30s (2 intervals >>> > of 10s with nearly 0 activity, one interval with a total amount of >>> > writes of ~120MB). The averages are : 4MB/s, 100 IO/s. >>> >>> Just a guess: >>> >>> btrfs has a commit interval which defaults to 30 seconds. >>> >>> You can verify this by changing the interval with the commit=XYZ mount >>> option. >> >> I know and I tested commit intervals of 60 and 120 seconds without >> any change. As this is directly linked to filestore max sync >> interval I didn't report this test result. >> >> Best regards, >> >> Lionel >> _______________________________________________ >> ceph-users mailing list >> ceph-users@xxxxxxxxxxxxxx <mailto:ceph-users@xxxxxxxxxxxxxx> >> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > > _______________________________________________ > ceph-users mailing list > ceph-users@xxxxxxxxxxxxxx <mailto:ceph-users@xxxxxxxxxxxxxx> > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > > > > _______________________________________________ > ceph-users mailing list > ceph-users@xxxxxxxxxxxxxx > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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