ext3 v. ext4 writeback mode

ext3 v. ext4 writeback mode

[Bojan Smojver]

Given this part of the diff between ext3.txt and ext4.txt in
Documentation/filesystems of 2.6.30-rc2, does that mean that ext4 in writeback
mode can still leave garbage in files after the crash?

-------------------------
 * writeback mode
-In data=writeback mode, ext3 does not journal data at all.  This mode provides
+In data=writeback mode, ext4 does not journal data at all.  This mode provides
 a similar level of journaling as that of XFS, JFS, and ReiserFS in its default
 mode - metadata journaling.  A crash+recovery can cause incorrect data to
 appear in files which were written shortly before the crash.  This mode will
-typically provide the best ext3 performance.
+typically provide the best ext4 performance.
-------------------------

Or is it just a quick cut'n'paste thing that never got rewritten?

--
Bojan

Re: ext3 v. ext4 writeback mode

[Bojan Smojver]

Bojan Smojver <bojan <at> rexursive.com> writes:

> Given this part of the diff between ext3.txt and ext4.txt in
> Documentation/filesystems of 2.6.30-rc2, does that mean that ext4 in writeback
> mode can still leave garbage in files after the crash?

Ted answered this in detail here:

http://lwn.net/Articles/329008/

Thanks!

--
Bojan