Subject: Re: nore on disk stats
To: None <perry@piermont.com>
From: Chris G Demetriou <Chris_G_Demetriou@BALVENIE.PDL.CS.CMU.EDU>
List: tech-install
Date: 11/10/1995 15:48:21
> Take the NCR driver, for instance:
>
> ncr0 targ 0 lun 0: <QUANTUM, XP34301, 1051> SCSI2 0/direct fixed
> sd0 at scsibus0sd0(ncr0:0:0): FAST SCSI-2 100ns (10 Mb/sec) offset 8.
> : 4106MB, 4076 cyl, 20 head, 103 sec, 512 bytes/sec
That's really a bug in the NCR driver, rather than anything else. (It
doesn't print negotiation messages in any 'sane', organized way.)
> Incidently, grabbing the <QUANTUM, XP34301, 1051> in a standard way
> would be neat, too [ ... ]
right now, the SCSI code attaches things like (minus ncr negotiation
printf):
ncr0: restart (scsi reset).
scsibus0 at ncr0
ncr0 targ 0 lun 0: <DEC, RZ26L (C) DEC, 442D> SCSI2 0/direct fixed
sd0 at scsibus0: 1001MB, 3117 cyl, 8 head, 82 sec, 512 bytes/sec
It think it would be done much better as:
scsibus0 at ncr0
sd0 at scsibus0 targ 0 lun 0: <DEC, RZ26L (C) DEC, 442D> SCSI2 0/direct fixed
sd0: 1001MB, 3117 cyl, 8 head, 82 sec, 512 bytes/sec
(and, for unsupported/unconfigured devices:
<DEC, RZ26L (C) DEC, 442D> SCSI2 0/direct fixed at scsibus0 targ 0 lun 0 not supported
or something similar)
There's some redundancy in the way it's done now, but the fact that
"ncr0 targ 0 lun 0" is sd0 is never directly established (as it is
with my version). Additionally, I don't really think that the current
way is in line with the way the configuration code is meant to be
used...
> Also, it would be nice if disk drives and network interfaces gave you
> enough information about themselves that you didn't need to hard code
> what the device names were -- among other things, that could help in
> trying to make the install stuff machine independent and more
> maintainable.
it's very easy to have a machine-specific list of devices of "given
types" -- haven't we gone through this before, already?
> > This is similar to the approach Paul and I took with the hp300/sparc (and
> > sun3, too) install.sh. Eventually, most (all?) ports might be able to
> > use this script after .'ing in a machine-dependent module that defines
> > certain functions.
>
> I'd rather see things standardize sufficiently that you don't need
> much in the way of machine dependant stuff at all...
I think that's unreasonable. either:
(1) there are machine-specific lists, or code to handle weird
devices,
(2) there are no machine-specific lists and every device
type is known to the machine-independent code and/or
'standardized'
(2) has some disadvantages:
(a) driver name collisions might cause problems,
(b) how are devices of a given type recognized? what
if there are two different types of drivers that
want 'similar' autoconfig output, but shouldn't
be treated identically? certainly, it's unacceptable
to have "le0: ETHERNET DEVICE" spit out at boot time...
8-)
chris