I can confirm that removing all the snapshots seems to resolve the problem. A - I would propose a redesign of something like that snapshots from below the mountpoint are only taken into account and not snapshots in the entire filesystem. That should fix a lot of issues B - That reminds me about this mv command, that does not move data across different pools in the fs. I would like to see this. Because it is the logical thing to expect. > >> > >> >ISTR there were some anti-spam measures put in place. Is your account >> >waiting for manual approval? If so, David should be able to help. >> >> Yes if I remember correctly I get waiting approval when I try to log in. >> >> >> >> >> >> >> >> >> Dec 1 03:14:36 c04 kernel: ceph: build_snap_context 100020c9287 >> >> ffff911a9a26bd00 fail -12 >> >> Dec 1 03:14:36 c04 kernel: ceph: build_snap_context 100020c9283 >> > >> > >> >It is failing to allocate memory. "low load" isn't very specific, >> >can you describe the setup and the workload in more detail? >> >> 4 nodes (osd, mon combined), the 4th node has local cephfs mount, which >> is rsync'ing some files from vm's. 'low load' I have sort of test setup, >> going to production. Mostly the nodes are below a load of 1 (except when >> the concurrent rsync starts) >> >> >How many snapshots do you have? >> >> Don't know how to count them. I have script running on a 2000 dirs. If >> one of these dirs is not empty it creates a snapshot. So in theory I >> could have 2000 x 7 days = 14000 snapshots. >> (btw the cephfs snapshots are in a different tree than the rsync is >> using) > >Is there a reason you are snapshotting each directory individually >instead of just snapshotting a common parent? Yes because I am not sure the snapshot frequency on all folders is going to be the same. >If you have thousands of snapshots, you may eventually hit a different >bug: > >https://tracker.ceph.com/issues/21420 >https://docs.ceph.com/docs/master/cephfs/experimental-features/#snapsh ots > >Be aware that each set of 512 snapshots amplify your writes by 4K in >terms of network consumption. With 14000 snapshots, a 4K write would >need to transfer ~109K worth of snapshot metadata to carry itself out. > Also when I am not even writing to a tree with snapshots enabled? I am rsyncing to dir3 . ├── dir1 │ ├── dira │ │ └── .snap │ ├── dirb │ ├── dirc │ │ └── .snap │ └── dird │ └── .snap ├── dir2 └── dir3 _______________________________________________ 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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