We're with a problem with filesystem corruption in guest machines in a XenServer 6.2
It only happens in Linux Machines. Randomly the filesystem remounts as read-only and them corruption starts on the root filesystem.
Here is some info from dmesg:
[894425.330993] end_request: I/O error, dev xvda, sector 768272
[894425.331019] Buffer I/O error on device dm-0, logical block 33058
[894425.331035] EXT4-fs warning (device dm-0): ext4_end_bio:250: I/O error writing to inode 2999 (offset 0 size 4096 starting block 33058)
[894425.331057] end_request: I/O error, dev xvda, sector 777616
[894425.331067] Buffer I/O error on device dm-0, logical block 34226
[894425.331079] EXT4-fs warning (device dm-0): ext4_end_bio:250: I/O error writing to inode 3010 (offset 0 size 4096 starting block 34226)
[894425.331093] end_request: I/O error, dev xvda, sector 5048224
[894425.331134] JBD2: Detected IO errors while flushing file data on dm-0-8
[894425.331162] Aborting journal on device dm-0-8.
[894425.331221] EXT4-fs error (device dm-0) in ext4_free_blocks:4766: Journal has aborted
[894457.732827] EXT4-fs (dm-0): Remounting filesystem read-only
[894457.732853] EXT4-fs error (device dm-0) in ext4_reserve_inode_write:4499: Journal has aborted
[894457.774125] EXT4-fs error (device dm-0) in ext4_reserve_inode_write:4499: Journal has aborted
[894457.840951] EXT4-fs error (device dm-0) in ext4_ext_remove_space:2742: Journal has aborted
[894457.841677] EXT4-fs error (device dm-0) in ext4_reserve_inode_write:4499: Journal has aborted
[894457.847755] EXT4-fs error (device dm-0) in ext4_orphan_del:2110: Journal has aborted
[894457.857108] EXT4-fs error (device dm-0) in ext4_reserve_inode_write:4499: Journal has aborted
[894457.858184] EXT4-fs error (device dm-0): ext4_journal_start_sb:327: Detected aborted journal
[980980.704070] EXT4-fs (dm-0): error count: 8
[980980.704087] EXT4-fs (dm-0): initial error at 1394156871: ext4_free_blocks:4766
[980980.704097] EXT4-fs (dm-0): last error at 1394156904: ext4_reserve_inode_write:4499
[994860.307102] adclient[2625]: segfault at 7fbfbb454660 ip 00007fbfb969b07d sp 00007fbfb63cc640 error 4 in libc-2.13.so[7fbfb9624000+182000]
[1067488.224066] EXT4-fs (dm-0): error count: 8
[1067488.224083] EXT4-fs (dm-0): initial error at 1394156871: ext4_free_blocks:4766
[1067488.224093] EXT4-fs (dm-0): last error at 1394156904: ext4_reserve_inode_write:4499
Searching across the internet points to some info about this problem with Debian and Ubuntu, in our case we use Debian Wheezy, but the workarround to set barrier=0 in the ext4 options in /etc/fstab makes no effect.
Any ideia how to debug this problem?
