On Mon, Feb 05, 2001 at 04:50:13PM -0000, Peter Galbavy wrote:
> > Soft Updates use magically delicious write ordering to provide the same
> kind of
> > metadata integrity protection as a journaling filesystem, but without any
> > changes to the underlying filesystem structure. Soft Update support is
> pretty
> > stable in OpenBSD 2.8. As long as
>
> With the greatest of respect, let me refer the gentlemen to the word
> "bollocks".
>
> Sorry, I felt like being frivolous. In reality, softupdates to not provide
> the most important part of a journaling file system, next to ordered writes,
> and that is zero-integrity checking at boot.

You are correct! That is important. SoftUpdates provides that feature.
SoftUpdates, like journaling, ensures metadata integrity. If you read through
section 6.1 of McKusick's implementation doc:

(http://www.usenix.org/publications/library/proceedings/usenix99/full_papers/mckusick/mckusick.ps)

it is explained how you can mount a SoftUpdate fs immediately, and run fsck
in the background to take care of any cleanup. (The cleanup is in relation
to unreferenced blocks and inode link counts, which does not effect stored
data and its related metadata.) OpenBSD's fsck does not yet support the
background check yet. I am not sure if any of the other BSDs do either. So,
SoftUpdates supports zero-integrity checking,
Nevermind the bollocks, here comes the SoftUpdates....

Is anyone working on adding full SoftUpdate checking/support into OpenBSD?

-Paul

-- 
/Paul M. Hirsch              /
/elektrosatanvoltagenoir.org/
/GPGPGPkeyID: 0xD11A250E     /

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