buttersink fails transferring large snapshot

[kovaga]

I wonder if anyone has experienced the similar behaviour of buttersink?

I am sending a relatively large snapshot to offsite backup via ssh 90.47 Gb and it fails at 66.61.
Have tried many times with different snapshots but it always fails at exactly 73%. The smaller snapshots are transferred fine.

Any ideas?

Remote version: {u'btrfs': u'btrfs-progs v4.15.1', u'buttersink': u'0.6.9', u'linux': u'Linux-5.0.10-050010-generic-x86_64-with-Ubuntu-18.04-bionic'}
Optimal synchronization:
213.4 GiB from 9 diffs in ssh://buttersink@nas/mnt/red_storage/backup-btrfs-snapshots/xpska
105.1 GiB from 36 diffs in btrfs //
318.5 GiB from 45 diffs in TOTAL
Keep: c389...d685 /mnt/red_storage/backup-btrfs-snapshots/xpska/.snapshots/704/snapshot from None (23.68 GiB)
Keep: 279a...453b /mnt/red_storage/backup-btrfs-snapshots/xpska/.snapshots/2/snapshot from None (23.65 GiB)
Keep: 0aaf...b557 /mnt/red_storage/backup-btrfs-snapshots/xpska/.snapshots/628/snapshot from None (23.91 GiB)
Xfer: c7aa...5c4e //home/.snapshots/661/snapshot from None (90.47 GiB)
btrfs send errorsnt 66.61 GiB of 90.47 GiB (73%) ETA: 0:05:53.112918 (580 Mbps )
At subvol //home/.snapshots/661/snapshot
ERROR: send ioctl failed with -5: Input/output error

[AmesCornish]

First thing is to try a btrfs transfer without buttersink. Try using btrfs send and receive and see what happens.

[kovaga]

Hi Ames,
tried sending using the nc, and the same thing happens.
I came across a post https://www.spinics.net/lists/linux-btrfs/msg70468.html indicating that such things might happen due to corrupt fs, so will investigate in this direction.

btrfs send -v /home/.snapshots/334/snapshot | pv | nc nas 6666 [20:40:36]

At subvol /home/.snapshots/334/snapshot
ERROR: send ioctl failed with -5: Input/output error
66,6GiB 0:10:25 [ 109MiB/s] [

[kovaga]

Having performed btrfs scrub on the / found several cheksum errors, once corrected, the send/receive functions normally.