Hi, in my 7 OSD node cluster I have the following disks: Node 1 48x 1.6TB Node 2 48x 1.6TB Node 3 48x 1.6TB Node 4 48x 1.6TB Node 5 48x 7.2TB Node 6 48x 7.2TB Node 7 48x 7.2TB The disk sizes are represented in CRUSH map accordingly. For these disks only I created a pool "hdb_backup" with size 3. Based on output of rados df this pool is using 247TB currently. root@ld3955:~# rados df POOL_NAME USED OBJECTS CLONES COPIES MISSING_ON_PRIMARY UNFOUND DEGRADED RD_OPS RD WR_OPS WR USED COMPR UNDER COMPR cephfs_data 345 GiB 99092 0 297276 0 0 0 1638 811 MiB 109235 365 GiB 0 B 0 B cephfs_metadata 102 MiB 48 0 144 0 0 0 8 8 KiB 8588 106 MiB 0 B 0 B hdb_backup 247 TiB 64671398 0 194014194 0 0 0 12902005 4.3 TiB 323647757 601 TiB 0 B 0 B hdd 2.4 TiB 635457 0 1270914 0 0 0 13237278 321 GiB 21526953 3.0 TiB 0 B 0 B nvme 0 B 0 0 0 0 0 0 0 0 B 0 0 B 0 B 0 B ssd 251 GiB 64307 0 128614 0 0 0 615475 29 GiB 885085 55 GiB 0 B 0 B total_objects 65470302 total_used 747 TiB total_avail 784 TiB total_space 1.5 PiB In order to rebalance the data in this pool I have configured balance mode upmap: root@ld3955:~# ceph balancer status { "active": true, "plans": [], "mode": "upmap" } Unfortunately the data distribution is not balanced at all on 1.6TB disks, means the range is between 53.37% and 83.04%. root@ld3955:~# ceph osd df | awk '{ print "osd."$1, "size: "$5, "usage: " $17, "reweight: "$4 }' | sort -nk5 osd.ID size: SIZE usage: reweight: REWEIGHT osd.MIN/MAX size: 26.45 usage: reweight: STDDEV: osd.TOTAL size: TiB usage: reweight: 747 osd.265 size: 1.6 usage: 53.37 reweight: 1.00000 osd.248 size: 1.6 usage: 53.41 reweight: 1.00000 osd.111 size: 1.6 usage: 53.43 reweight: 1.00000 osd.161 size: 1.6 usage: 53.46 reweight: 1.00000 osd.85 size: 1.6 usage: 53.46 reweight: 1.00000 osd.241 size: 1.6 usage: 53.49 reweight: 1.00000 osd.238 size: 1.6 usage: 53.51 reweight: 1.00000 osd.259 size: 1.6 usage: 53.56 reweight: 1.00000 osd.88 size: 1.6 usage: 53.57 reweight: 1.00000 osd.204 size: 1.6 usage: 53.58 reweight: 1.00000 osd.159 size: 1.6 usage: 55.16 reweight: 1.00000 osd.81 size: 1.6 usage: 55.16 reweight: 1.00000 osd.116 size: 1.6 usage: 55.20 reweight: 1.00000 osd.195 size: 1.6 usage: 55.25 reweight: 1.00000 osd.169 size: 1.6 usage: 55.33 reweight: 1.00000 osd.158 size: 1.6 usage: 55.34 reweight: 1.00000 [...] osd.146 size: 1.6 usage: 79.31 reweight: 1.00000 osd.140 size: 1.6 usage: 79.34 reweight: 0.89999 osd.262 size: 1.6 usage: 79.38 reweight: 0.89999 osd.217 size: 1.6 usage: 79.48 reweight: 1.00000 osd.83 size: 1.6 usage: 79.50 reweight: 1.00000 osd.239 size: 1.6 usage: 79.52 reweight: 0.79999 osd.190 size: 1.6 usage: 80.87 reweight: 1.00000 osd.97 size: 1.6 usage: 80.95 reweight: 1.00000 osd.216 size: 1.6 usage: 80.97 reweight: 1.00000 osd.160 size: 1.6 usage: 81.03 reweight: 1.00000 osd.145 size: 1.6 usage: 81.19 reweight: 1.00000 osd.137 size: 1.6 usage: 81.20 reweight: 0.89999 osd.136 size: 1.6 usage: 81.21 reweight: 0.89999 osd.54 size: 1.6 usage: 82.88 reweight: 1.00000 osd.252 size: 1.6 usage: 83.04 reweight: 0.89999 Question: Why is the data distribution on the 1.6TB disks unequal? How can I correct this? THX _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx