On Thu, Dec 7, 2017 at 11:59 PM, Reed Dier <reed.dier@xxxxxxxxxxx> wrote: >> You can try doubling (several times if necessary) the MDS configs >> `mds_log_max_segments` and `mds_log_max_expiring` to make it more >> aggressively trim its journal. (That may not help since your OSD >> requests are slow.) > > > This may be obvious, but where is this mds_log located, and what are the bottlenecks for it to get behind? > > Is this something that is located on an OSD? Is this located in the metadata pool (which I had previously moved to live on SSDs rather than colocated on the HDDs that the filesystem pool lives on)? logs are stored in cephfs metadata pool > Just curious what would be the bottleneck in the MDS trying to trim this log. > see https://github.com/ceph/ceph/pull/18783. there was bug in log trimming log. By default, it trim 20 segments at most in each tick (5 seconds by default) > I see the MDS process on the active MDS with decent CPU util, but not any real disk traffic from the MDS side. > > So just looking to see what is bounding me with the trimming to keep it so far behind (I increased both max segments and max expiring by 4x each). > > Thanks, > > Reed > _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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