On Sat, May 2, 2009 at 12:16 PM, Martin Herrman <mar...@herrman.nl> wrote: > > After reading this: > > http://ext4.wiki.kernel.org/index.php/Ext4_Howto#Converting_an_ext3_filesystem_to_ext4 > > do you have any experience with mounting your ext3 filesystems using the > ext4 module? Is the performance improvement noticeable?
I have my ext3 mounted using ext4 driver, but I don't notice anything better or worse. The on-disk structures are the same, obviously, so any improvement would be the difference between how ext4 driver handles the ext3 data in a different way (dealloc and mballoc, as that wiki page says). To really gain any improvement you'd need to use the new on-disk format, which the tune2fs stuff will do for any NEW files, but all existing files will still be old. You'd probably be better off making a backup, formatting as ext4, then restoring backup. However, with that being said, I used a freshly-formatted ext4 in my laptop and still don't notice any difference compared to when it had ext3.
