Le 23/02/2016 18:34, Marc MERLIN a écrit : > On Tue, Feb 23, 2016 at 09:26:35AM -0800, Marc MERLIN wrote: >> Label: 'dshelf2' uuid: d4a51178-c1e6-4219-95ab-5c5864695bfd >> Total devices 1 FS bytes used 4.25TiB >> devid 1 size 7.28TiB used 4.44TiB path /dev/mapper/dshelf2 >> >> btrfs fi df /mnt/btrfs_pool2/ >> Data, single: total=4.29TiB, used=4.18TiB >> System, DUP: total=64.00MiB, used=512.00KiB >> Metadata, DUP: total=77.50GiB, used=73.31GiB >> GlobalReserve, single: total=512.00MiB, used=31.22MiB >> >> Currently, it's btrfs on top of dmcrpyt on top of swraid5 > Sorry, I forgot to give the mount options: > /dev/mapper/dshelf2 on /mnt/dshelf2/backup type btrfs > (rw,noatime,compress=lzo,space_cache,skip_balance,subvolid=257,subvol=/backup)
Why don't you use autodefrag ? If you have writable snapshots and do write to them heavily it would not be a good idea (depending on how BTRFS handles this in most cases you would probably either break the reflinks or fragment a snapshot to defragment another) but if you only have read-only snapshots it may work for you (it does for me). The only BTRFS filesystems where I disabled autodefrag where Ceph OSDs with heavy in-place updates. Another option would have been to mark files NoCoW but I didn't want to abandon BTRFS checksumming. Lionel -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
