On Mon, Mar 18, 2019 at 6:05 PM Dylan McCulloch <dmc@xxxxxxxxxxxxxx> wrote: > > > > > >cephfs does not create/use object "4.00000000". Please show us some > >of its keys. > > > > https://pastebin.com/WLfLTgni > Thanks > Is the object recently modified? rados -p hpcfs_metadata stat 4.00000000 > >On Mon, Mar 18, 2019 at 4:16 PM Dylan McCulloch <dmc@xxxxxxxxxxxxxx> wrote: > >> > >> Hi all, > >> > >> We have a large omap object warning on one of our Ceph clusters. > >> The only reports I've seen regarding the "large omap objects" warning from other users were related to RGW bucket sharding, however we do not have RGW configured on this cluster. > >> The large omap object ~10GB resides in a CephFS metadata pool. > >> > >> It's perhaps worth mentioning that we had to perform disaster recovery steps [1] on this cluster last year after a network issue, so we're not sure whether this large omap object is a result of those previous recovery processes or whether it's completely unrelated. > >> > >> Ceph version: 12.2.8 > >> osd_objectstore: Bluestore > >> RHEL 7.5 > >> Kernel: 4.4.135-1.el7.elrepo.x86_64 > >> > >> We have set: "mds_bal_fragment_size_max": "500000" (Default 100000) > >> > >> $ ceph health detail > >> HEALTH_WARN 1 large omap objects > >> LARGE_OMAP_OBJECTS 1 large omap objects > >> 1 large objects found in pool 'hpcfs_metadata' > >> Search the cluster log for 'Large omap object found' for more details. > >> > >> # Find pg with large omap object > >> $ for i in `ceph pg ls-by-pool hpcfs_metadata | tail -n +2 | awk '{print $1}'`; do echo -n "$i: "; ceph pg $i query |grep num_large_omap_objects | head -1 | awk '{print $2}'; done | grep ": 1" > >> 20.103: 1 > >> > >> # OSD log entry showing relevant object > >> osd.143 osd.143 172.26.74.23:6826/3428317 1380 : cluster [WRN] Large omap object found. Object: 20:c0ce80d4:::4.00000000:head Key count: 24698995 Size (bytes): 11410935690 > >> > >> # Confirm default warning thresholds for large omap object > >> $ ceph daemon osd.143 config show | grep osd_deep_scrub_large_omap > >> "osd_deep_scrub_large_omap_object_key_threshold": "2000000", > >> "osd_deep_scrub_large_omap_object_value_sum_threshold": "1073741824", > >> > >> # Dump keys/values of problematic object, creates 46.65GB file > >> $ rados -p hpcfs_metadata listomapvals '4.00000000' > /tmp/hpcfs_metadata_object_omap_vals_4.00000000_20190304 > >> $ ll /tmp/hpcfs_metadata_object_omap_vals_4.00000000_20190304 > >> -rw-r--r-- 1 root root 50089561860 Mar 4 18:16 /tmp/hpcfs_metadata_object_omap_vals_4.00000000_20190304 > >> > >> # Confirm key count matches OSD log entry warning > >> $ rados -p hpcfs_metadata listomapkeys '4.00000000' | wc -l > >> 24698995 > >> > >> # The omap keys/vals for that object appear to have been unchanged/static for at least a couple of months: > >> $ sha1sum /tmp/hpcfs_metadata_object_omap_vals_4.00000000_20190304 > >> fd00ceb68607b477626178b2d81fefb926460107 /tmp/hpcfs_metadata_object_omap_vals_4.00000000_20190304 > >> $ sha1sum /tmp/hpcfs_metadata_object_omap_vals_4_00000000_20190108 > >> fd00ceb68607b477626178b2d81fefb926460107 /tmp/hpcfs_metadata_object_omap_vals_4_00000000_20190108 > >> > >> I haven't gone through all 24698995 keys yet, but while most appear to relate to objects in the hpcfs_data CephFS data pool, there are a significant number of keys (rough guess 25%) that don't appear to have corresponding objects in the hpcfs_data pool. > >> > >> Any assistance or pointers to troubleshoot further would be very much appreciated. > >> > >> Thanks, > >> Dylan > >> > >> [1] http://docs.ceph.com/docs/luminous/cephfs/disaster-recovery/ > >> > >> _______________________________________________ > >> ceph-users mailing list > >> ceph-users@xxxxxxxxxxxxxx > >> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > > > _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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