[ extract of message from Colin Wood on "Re: dmaintr: and esp0: ?" ]
} Steve Revilak wrote:
} > Recently, I installed NetBSD 1.3 on a Quadra 605 (with FPU), and I'm
} > experencing an anamoly that I'm not quite sure how to resolve.  The
} > following message lines keep appearing (although numbers are not always the
} > same).
} > 
} > Mar  6 13:39:40  /netbsd: dmaintr: discarded 32 b (last transfer was 1008
} > b).
} > Mar  6 13:39:40  /netbsd: esp0: !TC [intr 10, stat 87, step 4] prevphase 0,
} > resid 3f0
} > 
} > When booting in single user mode, it happens only occasionally.  When in
} > Multi-User, this message will appear every 30-120 seconds, sometimes
} > several at once.  Happens regardless of what I'm doing--running a program,
} > doing somethin at the command prompt.
} > 
} > The message lines seem most prone to appearing when a SCSI transaction is
} > taking place.  NetBSD is installed on a Syquest EZ135 removable.
} 
} My guess would be that you're getting bitten by the fact that NetBSD SCSI
} drivers seem to have a long history of _not_ liking removable media.
}  
} > Would presuming that there is a misconfiguration in either disktab, the
} > disklabel, or fstab be  correct?  For the sake of keeping this to a
} > reasonable length, I'll include only fstab and the disklabel.  If more info
} > is needed, I can supply that too.  I'm using the Generic 1.3 kernel.
} 
} I doubt that any of the above is the problem.
} 
} > Fsck also reports that the disk is getting trashed alot.  (Unallocated
} > blocks, unknown files).  I've already tried reformatting and re-installing.
} > Any help would be deeply appreciated.
} 
} The above isn't all that surprising.  Unfortunately, I don't know of any
} workarounds at the moment other than to try a non-removable SCSI disk.  If
} you get the chance, please file a PR on this problem, noting the exact
} error message (you can use the web form on www.netbsd.org if you don't
} want to use the send-pr command in NetBSD).
}

Unfortunately I don't think this has anything to do with removable media
as such. I think it has more to do with the LC475/Q605 motherboard + new
quadra SCSI driver not liking certain disks, particularly slow ones.

I have an LC475 and I had lots of identical problems with several Quantum
disks I own. The problem was worse the slower the disk was - with a fast
1Gig fireball I would very occasionally get such errors, with a medium speed
540MB fireball I would get it more often and with a slow 40MB quantum I got
it almost continuously. The problem seemed to occur more often when writing
to the disk rather then when reading from it.

I spoke to Allen Briggs about this problem four months or so ago, but he
wasn't able to find the problem at the time.

I bought a Segate 2Gig medalist disk and stuck it in the machine and have
never seen the problem again in several months of continuous operation.

	david

--

David Johnston
david@canopus.apana.org.au