UFS not handling errors correctly

Craig Boston cb at severious.net
Mon Sep 10 15:07:52 PDT 2007


On Mon, Sep 10, 2007 at 12:11:42AM +0200, Peter Schuller wrote:
> Kris Kenneway said:
> > Unfortunately there are many ways in which this can fail, mostly involving 
> > external factors violating the assumptions upon which soft updates relies.  
> > For example, the data written on disk may not correspond to the data 
> > dispatched by soft updates, due to things like write caching in the 
> > hardware, write reordering, data corruption, unpredictable disk behaviour 
> > during power loss, hardware failure, etc.
> 
> I am aware of this too (and paranoid about it).

Although it's still branded experimental for now, you may want to
look at ZFS after the 7.0 release.

There's a whole host of things to consider (different performance
characteristics, possible patent problems, etc), but it's one of the
most paranoid filesystems I've seen.  It doesn't really trust that the
disk actually works correctly and goes to great lengths to recover from
read failure or random data corruption.

It still sometimes panics on write failure, but that may be considered a
feature.

Craig


More information about the freebsd-fs mailing list