[Techtalk] Journalling file systems.

[Mary Gardiner]

On Sat, Oct 27, 2001 at 11:31:46AM +0800, Malcolm Tredinnick wrote:
> On Sat, Oct 27, 2001 at 09:45:46AM +1000, Mary Gardiner wrote:
> > I've been exposed to a three way holy war between xfs users, reiserfs
> > users and ext3fs users, but not a very informative one.
> 
> That would possibly be because there is no right answer.

Well, not in general, but there may be *for me* - hence the request for
pointers to where I can research :)

> > I'm looking for a good rundown on their comparitive strengths.
> 
> Have a browse through the archives of the kernel-traffic summaries
> (http://kt.zork.net/kernel-traffic/back-issues.html). Journalling
> filesystem threads are often covered there and sometimes different
> benchmarks are posted (which usually prove you can't prove anything).
> A few are mentioned, for example, in the thread at
> http://kt.zork.net/kernel-traffic/kt20010910_132.html#1.

Thanks.

> > * ext3: Can convert existing ext2 partitions without moving all the
> >   data, formatting, and moving back. Can put the journal file on a
> >   different partition so that the partition can be read as ext2 by, for
> >   example, a boot floppy.
> 
> Having the journal on a different partition if, I believe, not
> necessary. You can just mount the ext3 partition as type ext2 and it
> will be fine. When converting all my systems over to ext3, I ran tune2fs
> on different partitions, remounted a few as ext3, played around a bit,
> then rebooted. They came back as ext2 and nothing appeared to have been
> corrupted. This gave me some confidence that I wasn't about to destroy
> my system.

:)

I know it isn't compulsory to have the journal on a different partition,
but it has been sold to me as a possible alternative, parlty because
ext3 won't mount as ext2 if it wasn't cleanly unmounted
(http://www.uow.edu.au/~andrewm/linux/ext3/ext3-usage.html, the
"Switching" section).

> I think the correct solution is to line up three of your housemates, put
> labels on their heads (Reiser, ext3 and xfs) and then swing about wildly
> until you hit one. Choose that filesystem. Of course, I'd prefer if you
> didn't credit me with this method of choosing when you are explaining it
> to them. :)

Righto. I'll keep you posted on what my housemates think of having
hatpins stuck in them while I decide.

-Mary.

-- 
Mary Gardiner
<mary at puzzling.org>