Off-Topic Question

Joerg Sonnenberger joerg at britannica.bec.de
Wed Feb 16 09:25:25 PST 2005


On Wed, Feb 16, 2005 at 06:09:48PM +0100, Tom Hummel wrote:
> Can you point me to the necessity of adding journaling to UFS? I thought 
> Softdeps haven been a comparable solution to the same problem journaling 
> addresses. Both's performance penaltys over async metadata writes seem 
> to happen in the same universe.

(a) softdep is complex. *very* complex.
(b) softdep doesn't solve the problems of fast reboots after crash
(c) softdep doesn't allow replaying changes for off-site synchronisation

I consider softdep a useful concept for a filesystem, it can really
help for those filesystems we can't add a journaling later on top.
But having native journaling support can be much better.

Joerg





More information about the Bugs mailing list