In article <42D41345.9050809@iinet.net.au>,
	James Buchanan <jamesb.au@iinet.net.au> writes:
> Would anyone like to join in a discussion on implementing a new file 
> system for NetBSD with huge file system support (> 3TB) and journaling? 
>   I know soft updates on BSD systems do work like journaling, but I'm 
> not knowledgeable enough to say if one or the other is superior under 
> certain circumstances.

Soft dependences are a performance kludge in UFS which allows it to
work more asynchronously without risking data integrity. They don't
provide the protection against unclean system shutdown that a
journaling file system does.

> Can a new file system somehow be implemented in userland first before 
> adding it into a kernel?

Yes, it can. Userland programs can present itself to the kernel as
a NFS server. amd(8) and "pkgsrc/net/sharity-light" use such an
approach.

	Kind regards

-- 
Matthias Scheler                                  http://scheler.de/~matthias/