On Tue, 27 Aug 1996 08:31:40 -0700 
 "Justin T. Gibbs" <gibbs@freefall.freebsd.org> wrote:

[ Jukka sez... ]
 > >Is there any hope of improvement in the future?  This is a real problem
 > >for us.  CCD is just great, especially on news servers, but the SCSI
 > >driver problems limit the number of disks to two. :-(

Let's be a little more clear, here... The problem is that come models of 
the Adaptec controller (aic7xxx-family) have a rediculously small amount 
of RAM on them, limiting the number of commands they can concurrently 
process.  Under high-load conditions (which isn't much load, 
unfortunately, on these controllers), the NetBSD MI SCSI subsystem is 
unable to queue commands on these controllers due to resource shortage...

[ Justin sez... ]
 > ftp://Freefall.FreeBSD.org/incoming/scsi-diffs.96-815.gz
 > 
 > I have a lot of other changes in the pipe and will probably release another
 > snapshot today or tomorrow.  The plan is to port the entire MI layer to
 > NetBSD once I've incorperated all of NetBSD's improvements and the
 > interfaces have settled down a bit, but if someone wants to step in and track
 > these changes as they happen, be my guest.

Personally, I would really appreciate it if someone could track these 
changes somewhere ... I'd like to see these changes go in incrementally, 
in order to better stress-test the new code (on as many architectures as 
possible).

 -- save the ancient forests - http://www.bayarea.net/~thorpej/forest/ -- 
Jason R. Thorpe                                       thorpej@nas.nasa.gov
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