We have a 19.2.3 cluster managed by cephadm with five management nodes and 21 OSD nodes. We have roughly 300 linux clients across several subnets doing cephfs kernel mounts running a wide range of applications. Each management node has 760GB of memory. We’re currently using a single active MDS daemon, but have experimented with multiple MDS daemons and directory pinning. Each OSD for the cephfs data pool uses hdd (SATA) drives, with the DB and WAL on nvme's internal to the storage node. The cephfs metadata pool is on nvme drives internal to the management nodes. After a lot of testing in attempts to quiet down persistent MDS_CLIENT_LATE_RELEASE "clients failing to respond to capability release” and MDS_CLIENT_RECALL "clients failing to respond to cache pressure” warnings, we’ve ended up with the following settings. This seems to be working well. We still get periodic MDS_CLIENT_RECALL warnings, but not nearly as many as we were seeing and they clear relatively quickly. I’d greatly appreciate any suggestions for further improvements, or any concerns anyone has with these. Many thanks, Devin ——— cephfs session_timeout 120 mds mds_cache_memory_limit 549755813888 mds mds_cache_mid 0.700000 mds mds_cache_reservation 0.100000 mds mds_cache_trim_decay_rate 0.900000 mds mds_cache_trim_threshold 524288 mds mds_cap_revoke_eviction_timeout 30.000000 mds mds_health_cache_threshold 2.000000 mds mds_log_max_segments 256 mds mds_max_caps_per_client 5000000 mds mds_recall_global_max_decay_threshold 1048576 mds mds_recall_max_caps 5000 mds mds_recall_max_decay_rate 1.500000 mds mds_recall_max_decay_threshold 524288 mds mds_recall_warning_decay_rate 120.000000 mds mds_recall_warning_threshold 262144 ———