XFS log handling issue (with patch) -- (was Request for updated Ubuntu virtual kernel images)
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux (Ubuntu) |
Confirmed
|
Medium
|
Unassigned |
Bug Description
I have a Ubuntu 12.04 virtual machine with a 400 GB volume attached to it. This volume uses XFS filesystem on top of LVM2 setup and the backup system we use takes hourly backups. Since we freeze and unfreeze the filesystem during backups, I started seeing the following in the logs a lot.
Oct 14 06:52:35 localhost kernel: [4269962.940638] XFS (dm-1): xlog_space_left: head behind tail
Oct 14 06:52:35 localhost kernel: [4269962.940639] tail_cycle = 7, tail_bytes = 38953984
Oct 14 06:52:35 localhost kernel: [4269962.940640] GH cycle = 7, GH bytes = 38953976
Oct 14 06:52:35 localhost kernel: [4269962.940656] XFS (dm-1): xlog_space_left: head behind tail
Oct 14 06:52:35 localhost kernel: [4269962.940657] tail_cycle = 7, tail_bytes = 38953984
Oct 14 06:52:35 localhost kernel: [4269962.940657] GH cycle = 7, GH bytes = 38953976
This started occurred a lot and the backups were working fine for a day and then they started failing because they failed to remove the LVM snapshot using `lvremove`. After a little bit of research I found this commit in the linux kernel: https:/
This commit fixes this issue form kernel version 3.4 onwards. The most recent virtual kernel available for Ubuntu 12.04 LTS release is "3.2.0-49-virtual". So the possible solutions are to either backport the xfs fix to 3.2.x kernel or release virtual kernel releases for the latest version of the kernel.
I'll be happy to provide more information regarding this issue.
affects: | ubuntu → linux-meta (Ubuntu) |
affects: | linux-meta (Ubuntu) → linux (Ubuntu) |
summary: |
- Request for updated Ubuntu virtual kernel images + XFS log handling issue (with patch) -- (was Request for updated Ubuntu + virtual kernel images) |
Changed in linux (Ubuntu): | |
importance: | Undecided → Medium |
Status changed to 'Confirmed' because the bug affects multiple users.