My current settings are: mds advanced mds_beacon_grace 15.000000 mds basic mds_cache_memory_limit 4294967296 mds advanced mds_cache_trim_threshold 393216 global advanced mds_export_ephemeral_distributed true mds advanced mds_recall_global_max_decay_threshold 393216 mds advanced mds_recall_max_caps 30000 mds advanced mds_recall_max_decay_threshold 98304 mds advanced mds_recall_warning_threshold 196608 global advanced mon_compact_on_start true I haven't had any noticeable slow downs or crashes in a while with 3 active MDS and 3 hot standbys. On 14/12/2020 22:33, Patrick Donnelly wrote:
On Mon, Dec 7, 2020 at 12:06 PM Patrick Donnelly <pdonnell@redhat.com> wrote:
Hi Dan & Janek,
My understanding is that the recall thresholds (see my list below) should be scaled proportionally. OTOH, I haven't played with the decay rates (and don't know if there's any significant value to tuning those). I haven't gone through this thread yet but I want to note for those reading that we do now have documentation (thanks for the frequent
On Sat, Dec 5, 2020 at 6:26 AM Dan van der Ster <dan@vanderster.com> wrote: pokes Janek!) for the recall configurations:
https://docs.ceph.com/en/latest/cephfs/cache-configuration/#mds-recall
Please let us know if it's missing information or if something could be more clear. I also now have a PR open for updating the defaults based on these and other discussions: https://github.com/ceph/ceph/pull/38574
Feedback welcome.