To: linux-kernel@vger.kernel.org
From: Daniel Pittman <daniel@rimspace.net>
Subject: Re: mode data=journal in ext3. Is it safe to use?
Date: Thu, 17 Jun 2004 10:51:54 +1000
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On 17 Jun 2004, Timothy Miller wrote:
> Petter Larsen wrote:
>
>> Data integrity is much more important for us than speed.
>
> You might want to consider ReiserFS or one of the others which were
> designed with journaling in mind.  And I hope you're using RAID1 or
> RAID5.

I must admit, that isn't quite the response that I would have expected
for those requirements. :)

ReiserFS, XFS and (presumably) JFS all have considerably better
performance than ext3, for most tasks, because they were indeed designed
with journaling in mind.

OTOH, ReiserFS had an extremely long period of instability, and was
build by a group who felt that a working fsck was something you put
together after you got the filesystem working.

This, combined with the occasional "ReiserFS 3 ate my data" reports and
the reluctance of the developers to adapt to the 4K kernel stacks in
2.6.recent, would leave me hesitant to recommend it as "more
trustworthy" than ext3.


XFS, with the "null out data on recovery" mode, is less reliable than
ext3, full stop. It routinely destroys data in real world situations, a
secure, but irritating, choice.


ext3 remains the only journaling filesystem that I would, personally,
put any great degree of faith in, since it is still developed in a
cautious and safe fashion, and has a focus on getting the tools to
verify correctness in place before enabling kernel-side features.


Obviously, your millage may vary on these topics, as presumably have
your experiences.

Regards,
        Daniel
-- 
Advertising may be described as the science of arresting the human
intelligence long enough to get money from it.
        -- Stephen Leacock

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