Re: [ceph-users] cephfs 1 large omap objects
On Wed, Oct 30, 2019 at 9:28 AM Jake Grimmett wrote: > > Hi Zheng, > > Many thanks for your helpful post, I've done the following: > > 1) set the threshold to 1024 * 1024: > > # ceph config set osd \ > osd_deep_scrub_large_omap_object_key_threshold 1048576 > > 2) deep scrubbed all of the pgs on the two OSD that reported "Large omap > object found." - these were all in pool 1, which has just four osd. > > > Result: After 30 minutes, all deep-scrubs completed, and all "large omap > objects" warnings disappeared. > > ...should we be worried about the size of these OMAP objects? No. There are only a few of these objects and it's not caused problems up to now in any other cluster. -- Patrick Donnelly, Ph.D. He / Him / His Senior Software Engineer Red Hat Sunnyvale, CA GPG: 19F28A586F808C2402351B93C3301A3E258DD79D ___ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
Re: [ceph-users] cephfs 1 large omap objects
Hi Zheng, Many thanks for your helpful post, I've done the following: 1) set the threshold to 1024 * 1024: # ceph config set osd \ osd_deep_scrub_large_omap_object_key_threshold 1048576 2) deep scrubbed all of the pgs on the two OSD that reported "Large omap object found." - these were all in pool 1, which has just four osd. Result: After 30 minutes, all deep-scrubs completed, and all "large omap objects" warnings disappeared. ...should we be worried about the size of these OMAP objects? again many thanks, Jake On 10/30/19 3:15 AM, Yan, Zheng wrote: > see https://tracker.ceph.com/issues/42515. just ignore the warning for now > > On Mon, Oct 7, 2019 at 7:50 AM Nigel Williams > wrote: >> >> Out of the blue this popped up (on an otherwise healthy cluster): >> >> HEALTH_WARN 1 large omap objects >> LARGE_OMAP_OBJECTS 1 large omap objects >> 1 large objects found in pool 'cephfs_metadata' >> Search the cluster log for 'Large omap object found' for more details. >> >> "Search the cluster log" is somewhat opaque, there are logs for many >> daemons, what is a "cluster" log? In the ML history some found it in the OSD >> logs? >> >> Another post suggested removing lost+found, but using cephfs-shell I don't >> see one at the top-level, is there another way to disable this "feature"? >> >> thanks. >> >> ___ >> ceph-users mailing list >> ceph-users@lists.ceph.com >> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > ___ > ceph-users mailing list > ceph-users@lists.ceph.com > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > -- Jake Grimmett MRC Laboratory of Molecular Biology Francis Crick Avenue, Cambridge CB2 0QH, UK. ___ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
Re: [ceph-users] cephfs 1 large omap objects
see https://tracker.ceph.com/issues/42515. just ignore the warning for now On Mon, Oct 7, 2019 at 7:50 AM Nigel Williams wrote: > > Out of the blue this popped up (on an otherwise healthy cluster): > > HEALTH_WARN 1 large omap objects > LARGE_OMAP_OBJECTS 1 large omap objects > 1 large objects found in pool 'cephfs_metadata' > Search the cluster log for 'Large omap object found' for more details. > > "Search the cluster log" is somewhat opaque, there are logs for many daemons, > what is a "cluster" log? In the ML history some found it in the OSD logs? > > Another post suggested removing lost+found, but using cephfs-shell I don't > see one at the top-level, is there another way to disable this "feature"? > > thanks. > > ___ > ceph-users mailing list > ceph-users@lists.ceph.com > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com ___ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
Re: [ceph-users] cephfs 1 large omap objects
Hi Paul, Nigel, I'm also seeing "HEALTH_WARN 6 large omap objects" warnings with cephfs after upgrading to 14.2.4: The affected osd's are used (only) by the metadata pool: POOLID STORED OBJECTS USED %USED MAX AVAIL mds_ssd 1 64 GiB 1.74M 65 GiB 4.47 466 GiB See below for more log details. While I'm glad we can silence the warning, should I be worried about the values reported in the log causing real problems? many thanks Jake [root@ceph1 ~]# zgrep "Large omap object found" /var/log/ceph/ceph.log* /log/ceph/ceph.log-20191022.gz:2019-10-21 15:43:45.800608 osd.2 (osd.2) 262 : cluster [WRN] Large omap object found. Object: 1:e5134dd5:::10007b4b304.0240:head Key count: 524005 Size (bytes): 242090310 /var/log/ceph/ceph.log-20191022.gz:2019-10-21 15:43:48.440425 osd.2 (osd.2) 263 : cluster [WRN] Large omap object found. Object: 1:e5347802:::1000861ecf6.:head Key count: 395404 Size (bytes): 182676204 /var/log/ceph/ceph.log-20191025.gz:2019-10-24 23:53:25.348227 osd.2 (osd.2) 58 : cluster [WRN] Large omap object found. Object: 1:2f12e2d8:::10007b4b304.0180:head Key count: 1041988 Size (bytes): 481398012 /var/log/ceph/ceph.log-20191026.gz:2019-10-25 10:54:57.478636 osd.2 (osd.2) 69 : cluster [WRN] Large omap object found. Object: 1:effe741b:::1000763dfe6.:head Key count: 640788 Size (bytes): 296043612 /var/log/ceph/ceph.log-20191026.gz:2019-10-25 19:57:11.894099 osd.3 (osd.3) 326 : cluster [WRN] Large omap object found. Object: 1:4b4f7436:::10007b4b304.0200:head Key count: 522689 Size (bytes): 241482318 /var/log/ceph/ceph.log-20191027.gz:2019-10-27 02:30:10.648346 osd.3 (osd.3) 351 : cluster [WRN] Large omap object found. Object: 1:a47c6896:::1000894a736.:head Key count: 768126 Size (bytes): 354873768 On 10/8/19 10:27 AM, Paul Emmerich wrote: > Hi, > > the default for this warning changed recently (see other similar > threads on the mailing list), it was 2 million before 14.2.3. > > I don't think the new default of 200k is a good choice, so increasing > it is a reasonable work-around. > > Paul > -- Jake Grimmett MRC Laboratory of Molecular Biology Francis Crick Avenue, Cambridge CB2 0QH, UK. ___ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
Re: [ceph-users] cephfs 1 large omap objects
Hi, the default for this warning changed recently (see other similar threads on the mailing list), it was 2 million before 14.2.3. I don't think the new default of 200k is a good choice, so increasing it is a reasonable work-around. Paul -- Paul Emmerich Looking for help with your Ceph cluster? Contact us at https://croit.io croit GmbH Freseniusstr. 31h 81247 München www.croit.io Tel: +49 89 1896585 90 On Mon, Oct 7, 2019 at 3:37 AM Nigel Williams wrote: > > I've adjusted the threshold: > > ceph config set osd osd_deep_scrub_large_omap_object_key_threshold 35 > > Colleague suggested that this will take effect on the next deep-scrub. > > Is the default of 200,000 too small? will this be adjusted in future > releases or is it meant to be adjusted in some use-cases? > ___ > ceph-users mailing list > ceph-users@lists.ceph.com > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com ___ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
Re: [ceph-users] cephfs 1 large omap objects
I've adjusted the threshold: ceph config set osd osd_deep_scrub_large_omap_object_key_threshold 35 Colleague suggested that this will take effect on the next deep-scrub. Is the default of 200,000 too small? will this be adjusted in future releases or is it meant to be adjusted in some use-cases? ___ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
Re: [ceph-users] cephfs 1 large omap objects
I followed some other suggested steps, and have this: root@cnx-17:/var/log/ceph# zcat ceph-osd.178.log.?.gz|fgrep Large 2019-10-02 13:28:39.412 7f482ab1c700 0 log_channel(cluster) log [WRN] : Large omap object found. Object: 2:654134d2:::mds0_openfiles.0:head Key count: 306331 Size (bytes): 13993148 root@cnx-17:/var/log/ceph# ceph daemon osd.178 config show | grep osd_deep_scrub_large_omap "osd_deep_scrub_large_omap_object_key_threshold": "20", "osd_deep_scrub_large_omap_object_value_sum_threshold": "1073741824", root@cnx-11:~# rados -p cephfs_metadata stat 'mds0_openfiles.0' cephfs_metadata/mds0_openfiles.0 mtime 2019-10-06 23:37:23.00, size 0 ___ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com