Hi all, we have a new issue in our Nautilus cluster. The large omap warning seems to be more common for RGW usage, but we currently only use CephFS and RBD. I found one thread [1] regarding metadata pool, but it doesn't really help in our case. The deep-scrub of PG 36.6 brought up this message (deep-scrub finished with "ok"): 2019-09-30 20:18:22.548401 osd.9 (osd.9) 275 : cluster [WRN] Large omap object found. Object: 36:654134d2:::mds0_openfiles.0:head Key count: 238621 Size (bytes): 9994510 I checked xattr (none) and omapheader: ceph01:~ # rados -p cephfs-metadata listxattr mds0_openfiles.0 ceph01:~ # rados -p cephfs-metadata getomapheader mds0_openfiles.0 header (42 bytes) : 00000000 13 00 00 00 63 65 70 68 20 66 73 20 76 6f 6c 75 |....ceph fs volu| 00000010 6d 65 20 76 30 31 31 01 01 0d 00 00 00 74 c3 12 |me v011......t..| 00000020 00 00 00 00 00 01 00 00 00 00 |..........| 0000002a ceph01:~ # ceph fs volume ls [ { "name": "cephfs" } ] The respective OSD has default thresholds regarding large_omap: ceph02:~ # ceph daemon osd.9 config show | grep large_omap "osd_deep_scrub_large_omap_object_key_threshold": "200000", "osd_deep_scrub_large_omap_object_value_sum_threshold": "1073741824", Can anyone point me to a solution for this? Best regards, Eugen [1] http://lists.ceph.com/pipermail/ceph-users-ceph.com/2019-March/033813.html