On 4/15/19 2:55 PM, Igor Fedotov wrote: > Hi Wido, > > the main driver for this backport were multiple complains on write ops > latency increasing over time. > > E.g. see thread named: "ceph osd commit latency increase over time, > until restart" here. > > Or http://tracker.ceph.com/issues/38738 > > Most symptoms showed Stupid Allocator as a root cause for that. > > Hence we've got a decision to backport bitmap allocator which should > work a fix/workaround. >
I see, that makes things clear. Anything users should take into account when setting: [osd] bluestore_allocator = bitmap bluefs_allocator = bitmap Writing this here for archival purposes so that users who have the same question can find it easily. Wido > > Thanks, > > Igor > > > On 4/15/2019 3:39 PM, Wido den Hollander wrote: >> Hi, >> >> With the release of 12.2.12 the bitmap allocator for BlueStore is now >> available under Mimic and Luminous. >> >> [osd] >> bluestore_allocator = bitmap >> bluefs_allocator = bitmap >> >> Before setting this in production: What might the implications be and >> what should be thought of? >> >> From what I've read the bitmap allocator seems to be better in read >> performance and uses less memory. >> >> In Nautilus bitmap is the default, but L and M still default to stupid. >> >> Since the bitmap allocator was backported there must be a use-case to >> use the bitmap allocator instead of stupid. >> >> Thanks! >> >> Wido >> _______________________________________________ >> ceph-users mailing list >> ceph-users@lists.ceph.com >> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com _______________________________________________ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
