Ah, I see! The BIAS reflects the number of placement groups it should create. Since cephfs metadata pools are usually very small, but have many objects and high IO, the autoscaler gives them 4x the number of placement groups that it would normally give for that amount of data. So, your cephfs_data is set to a ratio of 0.9, and cephfs_metadata to 0.3? Are the two pools using entirely different device classes, so they are not sharing space? Anyway, I see that your overcommit is only "1.031x". So if you set cephfs_data to 0.85, it should go away. On Thu, Oct 24, 2019 at 10:09 AM Lars Täuber <taeuber@xxxxxxx> wrote: > > Thanks Nathan for your answer, > > but I set the the Target Ratio to 0.9. It is the cephfs_data pool that makes the troubles. > > The 4.0 is the BIAS from the cephfs_metadata pool. This "BIAS" is not explained on the page linked below. So I don't know its meaning. > > How can be a pool overcommited when it is the only pool on a set of OSDs? > > Best regards, > Lars > > Thu, 24 Oct 2019 09:39:51 -0400 > Nathan Fish <lordcirth@xxxxxxxxx> ==> Lars Täuber <taeuber@xxxxxxx> : > > The formatting is mangled on my phone, but if I am reading it correctly, > > you have set Target Ratio to 4.0. This means you have told the balancer > > that this pool will occupy 4x the space of your whole cluster, and to > > optimize accordingly. This is naturally a problem. Setting it to 0 will > > clear the setting and allow the autobalancer to work. > > > > On Thu., Oct. 24, 2019, 5:18 a.m. Lars Täuber, <taeuber@xxxxxxx> wrote: > > > > > This question is answered here: > > > https://ceph.io/rados/new-in-nautilus-pg-merging-and-autotuning/ > > > > > > But it tells me that there is more data stored in the pool than the raw > > > capacity provides (taking the replication factor RATE into account) hence > > > the RATIO being above 1.0 . > > > > > > How comes this is the case? - Data is stored outside of the pool? > > > How comes this is only the case when the autoscaler is active? > > > > > > Thanks > > > Lars > > > > > > > > > Thu, 24 Oct 2019 10:36:52 +0200 > > > Lars Täuber <taeuber@xxxxxxx> ==> ceph-users@xxxxxxx : > > > > My question requires too complex an answer. > > > > So let me ask a simple question: > > > > > > > > What does the SIZE of "osd pool autoscale-status" tell/mean/comes from? > > > > > > > > Thanks > > > > Lars > > > > > > > > Wed, 23 Oct 2019 14:28:10 +0200 > > > > Lars Täuber <taeuber@xxxxxxx> ==> ceph-users@xxxxxxx : > > > > > Hello everybody! > > > > > > > > > > What does this mean? > > > > > > > > > > health: HEALTH_WARN > > > > > 1 subtrees have overcommitted pool target_size_bytes > > > > > 1 subtrees have overcommitted pool target_size_ratio > > > > > > > > > > and what does it have to do with the autoscaler? > > > > > When I deactivate the autoscaler the warning goes away. > > > > > > > > > > > > > > > $ ceph osd pool autoscale-status > > > > > POOL SIZE TARGET SIZE RATE RAW CAPACITY RATIO > > > TARGET RATIO BIAS PG_NUM NEW PG_NUM AUTOSCALE > > > > > cephfs_metadata 15106M 3.0 2454G 0.0180 > > > 0.3000 4.0 256 on > > > > > cephfs_data 113.6T 1.5 165.4T 1.0306 > > > 0.9000 1.0 512 on > > > > > > > > > > > > > > > $ ceph health detail > > > > > HEALTH_WARN 1 subtrees have overcommitted pool target_size_bytes; 1 > > > subtrees have overcommitted pool target_size_ratio > > > > > POOL_TARGET_SIZE_BYTES_OVERCOMMITTED 1 subtrees have overcommitted > > > pool target_size_bytes > > > > > Pools ['cephfs_data'] overcommit available storage by 1.031x due > > > to target_size_bytes 0 on pools [] > > > > > POOL_TARGET_SIZE_RATIO_OVERCOMMITTED 1 subtrees have overcommitted > > > pool target_size_ratio > > > > > Pools ['cephfs_data'] overcommit available storage by 1.031x due > > > to target_size_ratio 0.900 on pools ['cephfs_data'] > > > > > > > > > > > > > > > Thanks > > > > > Lars > > > > > _______________________________________________ > > > > > ceph-users mailing list -- ceph-users@xxxxxxx > > > > > To unsubscribe send an email to ceph-users-leave@xxxxxxx > > > > _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
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