Description of problem: Converting a btrfs RAID10 filesystem to RAID1 using balance ends with ENOSPC errors although there should be ample space Version-Release number of selected component (if applicable): kernel-3.10.9-200.fc19.x86_64 How reproducible: Always Steps to Reproduce: # mkfs.btrfs -f -m raid10 -d raid10 /dev/sd{b,c,d,e,f,g} [...] # mount /dev/sdb /tank # btrfs filesystem show /dev/sdb Label: none uuid: 64fc9652-004c-4cf1-8be9-90e7a6ea546e Total devices 6 FS bytes used 28.00KB devid 6 size 2.73TB used 2.00GB path /dev/sdg devid 5 size 2.73TB used 2.00GB path /dev/sdf devid 4 size 2.73TB used 2.00GB path /dev/sde devid 3 size 2.73TB used 2.00GB path /dev/sdd devid 2 size 2.73TB used 2.00GB path /dev/sdc devid 1 size 2.73TB used 2.02GB path /dev/sdb # dd if=/dev/zero of=/tank/outfile bs=1M count=10k 10240+0 records in 10240+0 records out 10737418240 bytes (11 GB) copied, 19.3461 s, 555 MB/s # umount /tank # mount /dev/sdb /tank # md5sum /tank/outfile 2dd26c4d4799ebd29fa31e48d49e8e53 /tank/outfile # btrfs balance start -dconvert=raid1 -mconvert=raid1 /tank ERROR: error during balancing '/tank' - No space left on device There may be more info in syslog - try dmesg | tail --- [ 320.348412] device fsid 64fc9652-004c-4cf1-8be9-90e7a6ea546e devid 1 transid 8 /dev/sdb [ 320.350086] btrfs: disk space caching is enabled [ 320.351432] SELinux: initialized (dev sdg, type btrfs), uses xattr [ 453.781449] btrfs: relocating block group 12914130944 flags 65 [ 453.978438] btrfs: relocating block group 9692905472 flags 65 [ 463.650472] btrfs: found 3 extents [ 475.883302] btrfs: found 3 extents [ 476.117307] btrfs: relocating block group 6471680000 flags 65 [ 476.295196] btrfs: relocating block group 3250454528 flags 65 [ 476.450862] btrfs: relocating block group 29229056 flags 68 [ 477.161875] btrfs: found 3265 extents [ 477.351047] btrfs: relocating block group 20971520 flags 66 [ 477.550992] btrfs: found 2 extents [ 477.744960] btrfs: relocating block group 12582912 flags 1 [ 477.940231] btrfs: relocating block group 4194304 flags 4 [ 478.153028] btrfs: 3 enospc errors during balance --- # btrfs filesystem df /tank Data, RAID10: total=9.00GB, used=8.59GB Data, RAID1: total=11.00GB, used=1.41GB System, RAID1: total=32.00MB, used=12.00KB System: total=4.00MB, used=0.00 Metadata, RAID1: total=1.00GB, used=12.98MB # umount /tank # mount /dev/sdb /tank # md5sum /tank/outfile 2dd26c4d4799ebd29fa31e48d49e8e53 /tank/outfile The fs is still mountable, and the file seems to be intact. It seems the file is in some kind of limbo, part RAID10, part RAID1.
Not quite sure where to put this, but this is the kernel-bugzilla entry for this: https://bugzilla.kernel.org/show_bug.cgi?id=60808
*********** MASS BUG UPDATE ************** We apologize for the inconvenience. There is a large number of bugs to go through and several of them have gone stale. Due to this, we are doing a mass bug update across all of the Fedora 19 kernel bugs. Fedora 19 has now been rebased to 3.11.1-200.fc19. Please test this kernel update and let us know if you issue has been resolved or if it is still present with the newer kernel. If you experience different issues, please open a new bug report for those.
Fixed the upstream bugzilla.