> ...About one year ago I considered moving to a journaling file system, but
> opted not to because it seems like that's what WAL does for us already. How
> does putting a journaling file system under it add more reliability?
WAL only works if the WAL files are actually written to disk and can be
read off it again. Ext2 has a number of deficiencies which can cause
problems with this basic operation (inode corruptions, etc). Journaling
does not directly help.