BTW, it should be noted that with XFS or ext3 in metadata journal mode (data=writeback), and probably any other FS that journals metadata only (JFS?, reiser3/4 in some modes?), it is always a good idea to disable write caching on your drives (unless you're absolutely sure that they really do flush their caches on sync). You can do so by using the "write_cache = off" option in /etc/hdparm.conf (or the -W0 command line to hdparm).