GSoC proposition: multiplatform UFS2 driver

[Ian Lepore]

On Fri, 2014-03-14 at 15:27 +0000, RW wrote:
> On Thu, 13 Mar 2014 18:22:10 -0800
> Dieter BSD wrote:
> 
> > Julio writes,
> > > That being said, I do not like the idea of using NetBSD's UFS2
> > > code. It lacks Soft-Updates, which I consider to make FreeBSD UFS2
> > > second only to ZFS in desirability.
> > 
> > FFS has been in production use for decades.  ZFS is still wet behind
> > the ears. Older versions of NetBSD have soft updates, and they work
> > fine for me. I believe that NetBSD 6.0 is the first release without
> > soft updates.  They claimed that soft updates was "too difficult" to
> > maintain.  I find that soft updates are *essential* for data
> > integrity (I don't know *why*, I'm not a FFS guru). 
> 
> NetBSD didn't simply drop soft-updates, they replaced it with
> journalling, which is the approach used by practically all modern
> filesystems. 
> 
> A number of people on the questions list have said that they find
> UFS+SU to be considerably less robust than the journalled filesystems
> of other OS's.  

What I've seen claimed is that UFS+SUJ is less robust.  That's a very
different thing than UFS+SU.  Journaling was nailed onto the side of UFS
+SU as an afterthought, and it shows.

-- Ian