Hi Zakhar, you might want to try offline DB compaction using ceph-kvstore-tool for this specific OSD. Periodically we observe OSD perf drop due to degraded RocksDB performance, particularly after bulk data removal/migration.. Compaction is quite helpful in this case. Thanks, Igor On 26/04/2023 20:22, Zakhar Kirpichenko wrote:
Hi,
I have a Ceph 16.2.12 cluster with uniform hardware, same drive make/model, etc. A particular OSD is showing higher latency than usual in `ceph osd perf`, usually mid to high tens of milliseconds while other OSDs show low single digits, although its drive's I/O stats don't look different from those of other drives. The workload is mainly random 4K reads and writes, the cluster is being used as Openstack VM storage.
Is there a way to trace, which particular PG, pool and disk image or object cause this OSD's excessive latency? Is there a way to tell Ceph to
I would appreciate any advice or pointers.
Best regards, Zakhar _______________________________________________ ceph-users mailing list -- ceph-users@ceph.io To unsubscribe send an email to ceph-users-leave@ceph.io