On Sat, 3 Jul 1999 02:37:57 +0200 
 Thilo Manske <Thilo.Manske@HEH.Uni-Oldenburg.DE> wrote:

 > UBC branch?!? What's that?
 > 
 > I suppose that UBC means something like "Unified Buffer Cache",
 > but I didn't know that there's already code for/in NetBSD. (Cool!)
 > Have I missed something?

{Unified,UVM} Buffer Cache, sure :-)

The name is slightly borrowed from Digital UNIX's subsystem of the
same functionality (well, similar; UBC will actually be able to handle
some cases that the Digital UNIX UBC can't :-)

There's been some discussion of it on tech-kern, and there have
been quite a few commits to the chs-ubc and chs-ubc2 branches of the
source tree.

Chuck Silvers has been doing all the work.  What I've done on it so
far is sync the branch w/ -current (so that I can hack on it :-) and
do a few minor things that make non-converted file systems continue
to work (with the old buffer cache).

 > I really would like to know do when we will see UBC in -current
 > (maybe optional) or if patches for -current are available anywhere.

I doubt patches against -current will ever be distributed; it's
fairly invasive in some places.  This is also why there isn't simply
#ifdef UBC all over.

However, once anoncvs is finished being deployed (there *was* an
experimental server, but it's being moved to a production server),
you'll be able to check out the chs-ubc2 branch of the syssrc module.

 > BTW: I don't find any hints to the "UBC project" on the NetBSD
 > Project Server (http://mail-index.netbsd.org/cgi-bin/projects.cgi).

Nope, you're right.  The author evidently didn't choose to list
it there.

        -- Jason R. Thorpe <thorpej@nas.nasa.gov>