changes-only filesystem

[Yedidyah Bar-David]

On Sun, Sep 25, 2011 at 02:03:06PM +0300, Oleg Goldshmidt wrote:
> 2011/9/25 Erez D <erez0001 at gmail.com>:
> 
> > There used to be a filesystem which one would mount over a read-only
> > filesystem, and that filesystem would only hold the changes.
> >
> > anyone remembers which filesystem it was ?
> 
> UnionFS?
> 
> There is also MVFS from Rational (the basis of ClearCase), but it's
> proprietary and I doubt you meant it.

A few years ago lwn published a two-part review on a few such things:
http://lwn.net/Articles/324291/
http://lwn.net/Articles/327738/
You might read them through if interested, or just use as a list of
pointers to projects.
-- 
Didi