[ Cc: to <tech-kern@netbsd.org> removed ]

|> > therefore it would make sense to have at least 7 default devices for
|> > addressable devices (0-6).

Anyone who has more than four disks on a box is probably not Joe Average,
and can thus be reasonably expected to be able to MAKEDEV all he needs.

|> And traditionally id 6 is a tape drive...
|> These days 6 is more likely to be a CDROM.

Sun systems have different traditions - 0..3 disks, 4..5 tapes, 6 cdrom.

|> When we were sizing systems, it was generally not considered worthwhile
|> (from a throughput point of view) putting more than 1 disk on a scsi
|> channel.

"Configuration and Capacity Planning for Solaris Servers" shows some
test results which indicate that about four disks on a narrow bus and
eight to ten disks on a fast wide bus are optimal for access scenarios
which are likely to occur on mostly attribute intensive NFS servers.

Things are different for high volume data capture or video streaming,
of course.

	Volker