Hey ceph-users, may I ask (nag) again about this issue?  I am wondering if anybody can confirm my observations? I raised a bug https://tracker.ceph.com/issues/54136, but apart from the assignment to a dev a while ago here was not response yet. Maybe I am just holding it wrong, please someone enlighten me. Thank you and with kind regards Christian On 02/02/2022 20:10, Christian Rohmann wrote: > > Hey ceph-users, > > > I am debugging a mgr pg_autoscaler WARN which states a > target_size_bytes on a pool would overcommit the available storage. > There is only one pool with value for  target_size_bytes (=5T) defined > and that apparently would consume more than the available storage: > > --- cut --- > # ceph health detail > HEALTH_WARN 1 subtrees have overcommitted pool target_size_bytes > [WRN] POOL_TARGET_SIZE_BYTES_OVERCOMMITTED: 1 subtrees have > overcommitted pool target_size_bytes >     Pools ['backups', 'images', 'device_health_metrics', '.rgw.root', > 'redacted.rgw.control', 'redacted.rgw.meta', 'redacted.rgw.log', > 'redacted.rgw.otp', 'redacted.rgw.buckets.index', > 'redacted.rgw.buckets.data', 'redacted.rgw.buckets.non-ec'] overcommit > available storage by 1.011x due to target_size_bytes 15.0T on pools > ['redacted.rgw.buckets.data']. > --- cut --- > > > But then looking at the actual usage it seems strange that 15T (5T * 3 > replicas) should not fit onto the remaining 122 TiB AVAIL: > > > --- cut --- > # ceph df detail > --- RAW STORAGE --- > CLASS  SIZE     AVAIL    USED     RAW USED  %RAW USED > hdd    293 TiB  122 TiB  171 TiB   171 TiB      58.44 > TOTAL  293 TiB  122 TiB  171 TiB   171 TiB      58.44 > > --- POOLS --- > POOL                             ID  PGS   STORED   (DATA) (OMAP)   > OBJECTS  USED     (DATA)   (OMAP)   %USED  MAX AVAIL QUOTA OBJECTS  > QUOTA BYTES  DIRTY  USED COMPR  UNDER COMPR > backups                           1  1024   92 TiB   92 TiB  3.8 MiB   > 28.11M  156 TiB  156 TiB   11 MiB  64.77     28 TiB N/A            > N/A            N/A      39 TiB      123 TiB > images                            2    64  1.7 TiB  1.7 TiB  249 KiB  > 471.72k  5.2 TiB  5.2 TiB  748 KiB   5.81     28 TiB N/A            > N/A            N/A         0 B          0 B > device_health_metrics            19     1   82 MiB      0 B   82 > MiB       43  245 MiB      0 B  245 MiB      0     28 TiB > N/A            N/A            N/A         0 B          0 B > .rgw.root                        21    32   23 KiB   23 KiB 0 B       > 25  4.1 MiB  4.1 MiB      0 B      0     28 TiB N/A            > N/A            N/A         0 B          0 B > redacted.rgw.control             22    32      0 B      0 B 0 B        > 8      0 B      0 B      0 B      0     28 TiB N/A            > N/A            N/A         0 B          0 B > redacted.rgw.meta                23    32  1.7 MiB  394 KiB  1.3 > MiB    1.38k  237 MiB  233 MiB  3.9 MiB      0     28 TiB > N/A            N/A            N/A         0 B          0 B > redacted.rgw.log                 24    32   53 MiB  500 KiB   53 > MiB    7.60k  204 MiB   47 MiB  158 MiB      0     28 TiB > N/A            N/A            N/A         0 B          0 B > redacted.rgw.otp                 25    32  5.2 KiB      0 B  5.2 > KiB        0   16 KiB      0 B   16 KiB      0     28 TiB > N/A            N/A            N/A         0 B          0 B > redacted.rgw.buckets.index       26    32  1.2 GiB      0 B  1.2 > GiB    7.46k  3.5 GiB      0 B  3.5 GiB      0     28 TiB > N/A            N/A            N/A         0 B          0 B > redacted.rgw.buckets.data        27   128  3.1 TiB  3.1 TiB 0 B    > 3.53M  9.5 TiB  9.5 TiB      0 B  10.11     28 TiB N/A            > N/A            N/A         0 B          0 B > redacted.rgw.buckets.non-ec      28    32      0 B      0 B 0 B        > 0      0 B      0 B      0 B      0     28 TiB N/A            > N/A            N/A         0 B          0 B > --- cut --- > > > I then looked at how those values are determined at > https://github.com/ceph/ceph/blob/9f723519257eca039126a20aa6a2a7d2dbfb5dba/…. > Apparently "total_bytes" are compared with the capacity of the > root_map. I added a debug line and found that the total in my cluster > was already at: > >   total=325511007759696 > > so in excess of 300 TiB - Looking at "ceph df" again this usage seems > strange. > > > > Looking at how this total is calculated at > https://github.com/ceph/ceph/blob/9f723519257eca039126a20aa6a2a7d2dbfb5dba/…, > you see that the larger value (max) of "actual_raw_used" vs. > "target_bytes*raw_used_rate" is determined and then summed up. > > > I dumped the values for all pools my cluster with yet another line of > debug code: > > ---cut --- > pool_id 1 - actual_raw_used=303160109187420.0, target_bytes=0 > raw_used_rate=3.0 > pool_id 2 - actual_raw_used=5714098884702.0, target_bytes=0 > raw_used_rate=3.0 > pool_id 19 - actual_raw_used=256550760.0, target_bytes=0 raw_used_rate=3.0 > pool_id 21 - actual_raw_used=71433.0, target_bytes=0 raw_used_rate=3.0 > pool_id 22 - actual_raw_used=0.0, target_bytes=0 raw_used_rate=3.0 > pool_id 23 - actual_raw_used=5262798.0, target_bytes=0 raw_used_rate=3.0 > pool_id 24 - actual_raw_used=162299940.0, target_bytes=0 raw_used_rate=3.0 > pool_id 25 - actual_raw_used=16083.0, target_bytes=0 raw_used_rate=3.0 > pool_id 26 - actual_raw_used=3728679936.0, target_bytes=0 > raw_used_rate=3.0 > pool_id 27 - actual_raw_used=10035209699328.0, > target_bytes=5497558138880 raw_used_rate=3.0 > pool_id 28 - actual_raw_used=0.0, target_bytes=0 raw_used_rate=3.0 > --- cut --- > > > All values but those of pool_id 1 (backups) make sense. For backups > it's just reporting a MUCH larger actual_raw_used value than what is > shown via ceph df. > The only difference of that pool compared to the others is the enabled > compression: > > > --- cut --- > # ceph osd pool get backups compression_mode > compression_mode: aggressive > --- cut --- > > > Apparently there already was a similar issue > (https://tracker.ceph.com/issues/41567) with a resulting commit > (https://github.com/ceph/ceph/commit/dd6e752826bc762095be4d276e3c1b8d31293eb0) > > changing which from "bytes_used" to the "stored" field for > "pool_logical_used". > > But how does that take compressed (away) data into account? Does > "bytes_used" count all the "stored" bytes, summing up all uncompressed > bytes for pools with compression? > This surely must be a bug then, as those bytes are not really > "actual_raw_used". > > > > I was about to raise a bug, but I wanted to ask here on the ML first > if I misunderstood the mechanisms at play here. > Thanks and with kind regards, > > > Christian >