Questions regarding journal replay

[Theodore Tso]

On Wed, Feb 25, 2009 at 07:11:08PM +0100, Ralf Hildebrandt wrote:
> > TBH external journals probably aren't tested that much (though they
> > certainly should work)
> > 
> > I'll give it a quick sanity test on ext4.
> 
> They DO work, but apparently the docs are wrong! I mean, no sane
> person needs 32GB of journal

The docs don't warn against needing that large of a journal, yes.  One
of the things which never got finished (although it was in the
original design of the jbd layer) was the ability to share the journal
across multiple filesystems.  This would mean that it might more sense
to have a single large journal.  Probably not 32GB in size, though. 

Did you find some documentation that actually recommend that large of
an external journal?

					- Ted