Hi Torkil, I have looked at the files that you attached. They were helpful: pool 11 is problematic, it complains about degraded objects for no obvious reason. I think that is the blocker. I also noted that you mentioned peering problems, and I suspect that they are not completely resolved. As a somewhat-irrational move, to confirm this theory, you can restart osd.237 (it is mentioned at the end of query.11.fff.txt, although I don't understand why it is there) and then osd.298 (it is the primary for that pg) and see if any additional backfills are unblocked after that. Also, please re-query that PG again after the OSD restart. On Sun, Mar 24, 2024 at 4:56 AM Torkil Svensgaard <torkil@xxxxxxxx> wrote: > > > > On 23-03-2024 21:19, Alexander E. Patrakov wrote: > > Hi Torkil, > > Hi Alexander > > > I have looked at the CRUSH rules, and the equivalent rules work on my > > test cluster. So this cannot be the cause of the blockage. > > Thank you for taking the time =) > > > What happens if you increase the osd_max_backfills setting temporarily? > > We already had the mclock override option in place and I re-enabled our > babysitter script which sets osd_max_backfills pr OSD to 1-3 depending > on how full they are. Active backfills went from 16 to 53 which is > probably because default osd_max_backfills for mclock is 1. > > I think 53 is still a low number of active backfills given the large > percentage misplaced. > > > It may be a good idea to investigate a few of the stalled PGs. Please > > run commands similar to this one: > > > > ceph pg 37.0 query > query.37.0.txt > > ceph pg 37.1 query > query.37.1.txt > > ... > > and the same for the other affected pools. > > A few samples attached. > > > Still, I must say that some of your rules are actually unsafe. > > > > The 4+2 rule as used by rbd_ec_data will not survive a > > datacenter-offline incident. Namely, for each PG, it chooses OSDs from > > two hosts in each datacenter, so 6 OSDs total. When a datacenter is > > offline, you will, therefore, have only 4 OSDs up, which is exactly > > the number of data chunks. However, the pool requires min_size 5, so > > all PGs will be inactive (to prevent data corruption) and will stay > > inactive until the datacenter comes up again. However, please don't > > set min_size to 4 - then, any additional incident (like a defective > > disk) will lead to data loss, and the shards in the datacenter which > > went offline would be useless because they do not correspond to the > > updated shards written by the clients. > > Thanks for the explanation. This is an old pool predating the 3 DC setup > and we'll migrate the data to a 4+5 pool when we can. > > > The 4+5 rule as used by cephfs.hdd.data has min_size equal to the > > number of data chunks. See above why it is bad. Please set min_size to > > 5. > > Thanks, that was a leftover for getting the PGs to peer (stuck at > creating+incomplete) when we created the pool. It's back to 5 now. > > > The rbd.ssd.data pool seems to be OK - and, by the way, its PGs are > > 100% active+clean. > > There is very little data in this pool, that is probably the main reason. > > > Regarding the mon_max_pg_per_osd setting, you have a few OSDs that > > have 300+ PGs, the observed maximum is 347. Please set it to 400. > > Copy that. Didn't seem to make a difference though, and we have > osd_max_pg_per_osd_hard_ratio set to 5.000000. > > Mvh. > > Torkil > > > On Sun, Mar 24, 2024 at 3:16 AM Torkil Svensgaard <torkil@xxxxxxxx> wrote: > >> > >> > >> > >> On 23-03-2024 19:05, Alexander E. Patrakov wrote: > >>> Sorry for replying to myself, but "ceph osd pool ls detail" by itself > >>> is insufficient. For every erasure code profile mentioned in the > >>> output, please also run something like this: > >>> > >>> ceph osd erasure-code-profile get prf-for-ec-data > >>> > >>> ...where "prf-for-ec-data" is the name that appears after the words > >>> "erasure profile" in the "ceph osd pool ls detail" output. > >> > >> [root@lazy ~]# ceph osd pool ls detail | grep erasure > >> pool 11 'rbd_ec_data' erasure profile DRCMR_k4m2 size 6 min_size 5 > >> crush_rule 0 object_hash rjenkins pg_num 4096 pgp_num 4096 > >> autoscale_mode off last_change 2257933 lfor 0/1291190/1755101 flags > >> hashpspool,ec_overwrites,selfmanaged_snaps,bulk stripe_width 16384 > >> fast_read 1 compression_algorithm snappy compression_mode aggressive > >> application rbd > >> pool 37 'cephfs.hdd.data' erasure profile DRCMR_k4m5_datacenter_hdd size > >> 9 min_size 4 crush_rule 7 object_hash rjenkins pg_num 2048 pgp_num 2048 > >> autoscale_mode off last_change 2257933 lfor 0/0/2139486 flags > >> hashpspool,ec_overwrites,bulk stripe_width 16384 fast_read 1 > >> compression_algorithm zstd compression_mode aggressive application cephfs > >> pool 38 'rbd.ssd.data' erasure profile DRCMR_k4m5_datacenter_ssd size 9 > >> min_size 5 crush_rule 8 object_hash rjenkins pg_num 32 pgp_num 32 > >> autoscale_mode warn last_change 2198930 lfor 0/2198930/2198928 flags > >> hashpspool,ec_overwrites,selfmanaged_snaps stripe_width 16384 > >> compression_algorithm zstd compression_mode aggressive application rbd > >> > >> [root@lazy ~]# ceph osd erasure-code-profile get DRCMR_k4m2 > >> crush-device-class=hdd > >> crush-failure-domain=host > >> crush-root=default > >> jerasure-per-chunk-alignment=false > >> k=4 > >> m=2 > >> plugin=jerasure > >> technique=reed_sol_van > >> w=8 > >> [root@lazy ~]# ceph osd erasure-code-profile get DRCMR_k4m5_datacenter_hdd > >> crush-device-class=hdd > >> crush-failure-domain=datacenter > >> crush-root=default > >> jerasure-per-chunk-alignment=false > >> k=4 > >> m=5 > >> plugin=jerasure > >> technique=reed_sol_van > >> w=8 > >> [root@lazy ~]# ceph osd erasure-code-profile get DRCMR_k4m5_datacenter_ssd > >> crush-device-class=ssd > >> crush-failure-domain=datacenter > >> crush-root=default > >> jerasure-per-chunk-alignment=false > >> k=4 > >> m=5 > >> plugin=jerasure > >> technique=reed_sol_van > >> w=8 > >> > >> But as I understand it those profiles are only used to create the > >> initial crush rule for the pool, and we have manually edited those along > >> the way. Here are the 3 rules in use for the 3 EC pools: > >> > >> rule rbd_ec_data { > >> id 0 > >> type erasure > >> step set_chooseleaf_tries 5 > >> step set_choose_tries 100 > >> step take default class hdd > >> step choose indep 0 type datacenter > >> step chooseleaf indep 2 type host > >> step emit > >> } > >> rule cephfs.hdd.data { > >> id 7 > >> type erasure > >> step set_chooseleaf_tries 5 > >> step set_choose_tries 100 > >> step take default class hdd > >> step choose indep 0 type datacenter > >> step chooseleaf indep 3 type host > >> step emit > >> } > >> rule rbd.ssd.data { > >> id 8 > >> type erasure > >> step set_chooseleaf_tries 5 > >> step set_choose_tries 100 > >> step take default class ssd > >> step choose indep 0 type datacenter > >> step chooseleaf indep 3 type host > >> step emit > >> } > >> > >> Which should first pick all 3 datacenters in the choose step and then > >> either 2 or 3 hosts in the chooseleaf step, matching EC 4+2 and 4+5 > >> respectively. > >> > >> Mvh. > >> > >> Torkil > >> > >>> On Sun, Mar 24, 2024 at 1:56 AM Alexander E. Patrakov > >>> <patrakov@xxxxxxxxx> wrote: > >>>> > >>>> Hi Torkil, > >>>> > >>>> I take my previous response back. > >>>> > >>>> You have an erasure-coded pool with nine shards but only three > >>>> datacenters. This, in general, cannot work. You need either nine > >>>> datacenters or a very custom CRUSH rule. The second option may not be > >>>> available if the current EC setup is already incompatible, as there is > >>>> no way to change the EC parameters. > >>>> > >>>> It would help if you provided the output of "ceph osd pool ls detail". > >>>> > >>>> On Sun, Mar 24, 2024 at 1:43 AM Alexander E. Patrakov > >>>> <patrakov@xxxxxxxxx> wrote: > >>>>> > >>>>> Hi Torkil, > >>>>> > >>>>> Unfortunately, your files contain nothing obviously bad or suspicious, > >>>>> except for two things: more PGs than usual and bad balance. > >>>>> > >>>>> What's your "mon max pg per osd" setting? > >>>>> > >>>>> On Sun, Mar 24, 2024 at 1:08 AM Torkil Svensgaard <torkil@xxxxxxxx> wrote: > >>>>>> > >>>>>> On 2024-03-23 17:54, Kai Stian Olstad wrote: > >>>>>>> On Sat, Mar 23, 2024 at 12:09:29PM +0100, Torkil Svensgaard wrote: > >>>>>>>> > >>>>>>>> The other output is too big for pastebin and I'm not familiar with > >>>>>>>> paste services, any suggestion for a preferred way to share such > >>>>>>>> output? > >>>>>>> > >>>>>>> You can attached files to the mail here on the list. > >>>>>> > >>>>>> Doh, for some reason I was sure attachments would be stripped. Thanks, > >>>>>> attached. > >>>>>> > >>>>>> Mvh. > >>>>>> > >>>>>> Torkil > >>>>> > >>>>> > >>>>> > >>>>> -- > >>>>> Alexander E. Patrakov > >>>> > >>>> > >>>> > >>>> -- > >>>> Alexander E. Patrakov > >>> > >>> > >>> > >> > >> -- > >> Torkil Svensgaard > >> Systems Administrator > >> Danish Research Centre for Magnetic Resonance DRCMR, Section 714 > >> Copenhagen University Hospital Amager and Hvidovre > >> Kettegaard Allé 30, 2650 Hvidovre, Denmark > >> > > > > > > -- > Torkil Svensgaard > Systems Administrator > Danish Research Centre for Magnetic Resonance DRCMR, Section 714 > Copenhagen University Hospital Amager and Hvidovre > Kettegaard Allé 30, 2650 Hvidovre, Denmark -- Alexander E. Patrakov _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx