I have a Luminous 12.2.7 cluster with 2 EC pools, both using k=8 and m=2. Each pool lives on 20 dedicated OSD hosts with 18 OSDs each. Each pool has 2048 PGs and is distributed across its 360 OSDs with host failure domains. The OSDs are identical (4TB) and are weighted with default weights (3.73). Initially, and not surprisingly, the PG distribution was all over the place with PG counts per OSD ranging from 40 to 83. I enabled the balancer module in upmap mode and let it work its magic, which reduced the range of the per-OSD PG counts to 56-61. While 56-61 is obviously a whole lot better than 40-83, with upmap I expected the range to be 56-57. If I run 'ceph balancer optimize <plan>' again to attempt to create a new plan I get 'Error EALREADY: Unable to find further optimization,or distribution is already perfect.' I set the balancer's max_misplaced value to 1 in case that was preventing further optimization, but I still get the same error. I'm sure I'm missing some config option or something that will allow it to do better, but thus far I haven't been able to find anything in the docs, mailing list archives, or balancer source code that helps. Any ideas? Steve Taylor | Senior Software Engineer | StorageCraft Technology Corporation 380 Data Drive Suite 300 | Draper | Utah | 84020 Office: 801.871.2799 | If you are not the intended recipient of this message or received it erroneously, please notify the sender and delete it, together with any attachments, and be advised that any dissemination or copying of this message is prohibited. _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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