System freeze on Ubuntu Jaunty (9.04) with ext4
If you set snapshots directory on a ext4 partition the system may freeze.
It seems to be a problem in ext4 on Ubuntu:
- https://bugs.launchpad.net/ubuntu/+source/linux/+bug/330824
- http://thunk.org/tytso/blog/2009/03/12/delayed-allocation-and-the-zero-length-file-problem/
Solution (thanks to mahikeulbody)
You need to set ‘nodelalloc’ option for each ext4 partition it accesses into fstab file .
2 Responses to “System freeze on Ubuntu Jaunty (9.04) with ext4”
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blurpo on December 25th, 2009
It doesn’t help for me. I have Ubuntu 9.10 64-bit, ext4 filesystem mounted with the nodelalloc option.
A backup job start with the command:
> backintime -b
will hang with the following stacktrace:
INFO: Save permissions
Traceback (most recent call last):
File “/usr/share/backintime/common/backintime.py”, line 174, in
start_app()
File “/usr/share/backintime/common/backintime.py”, line 86, in start_app
take_snapshot( cfg, True )
File “/usr/share/backintime/common/backintime.py”, line 42, in take_snapshot
snapshots.Snapshots( cfg ).take_snapshot( force )
File “/usr/share/backintime/common/snapshots.py”, line 424, in take_snapshot
ret_val = self._take_snapshot( snapshot_id, now, include_folders, ignore_folders, dict, force )
File “/usr/share/backintime/common/snapshots.py”, line 724, in _take_snapshot
fileinfo.close()
IOError: [Errno 5] Input/output error
This was the same before I mounted with nodelalloc.
Note that it is the filesystem that I’m backing up that is ext4. The filesystem I’m writing the backup to, is a remote disk on a NAS mounted using FTP, using curlftpfs. (The filesystem of the remote disk is xfs, but I doubt that that’s relevant?)
faber on May 12th, 2010
I’m currently backin up into an external ext4 partition with backintime 0.9.26 and ubuntu 9.10 x86_64 and I hopefully have no problems