[]ext4
インストールしたあとに見つけたやつ
要リリースノート
http://www.ubuntu.com/getubuntu/releasenotes/910
Possible corruption of large files with ext4 filesystem
There have been some reports of data corruption with fresh (not upgraded) ext4 file systems using the Ubuntu 9.10 kernel when writing to large files (over 512MB). The issue is under investigation, and if confirmed will be resolved in a post-release update. Users who routinely manipulate large files may want to consider using ext3 file systems until this issue is resolved.