Re: softdeps and NetBSD 6.0

[Matthias Scheler <tron%zhadum.org.uk@localhost>]

On Tue, Sep 22, 2009 at 11:29:07AM -0700, Dieter wrote:
> > softdeps are scheduled to be removed in 6.0
> 
> WHY?  WHY?  WHY?

Because the softdep code has a lot of problems. It can e.g. lock up your
system the right (or wrong?) access pattern. WAPBL also avoids long
lasting file-system checks after a system crash.

> Softdeps are ABSOLUTELY REQUIRED!

WAPBL provides similar performance gains as soft dependences.
Please have a look at the following articles:

http://zhadum.org.uk/2008/07/31/journaling-at-last/
http://zhadum.org.uk/2008/08/23/wapbl-vs-soft-dependences/

If you want to know more about WAPBL please have a look at the slides
of Jörg Sonnenberger's presentation from the EuroBSDCon 2009:

http://www.netbsd.org/gallery/presentations/joerg/bsdcan2009/wapbl.html

        Kind regards

-- 
Matthias Scheler                                  http://zhadum.org.uk/