Re: SCSI Kernel Problem - BAD

Simon Shapiro (Shimon@i-connect.net)
Mon, 11 Mar 1996 16:20:30 -0600 (CST)

Hi "Leonard N. Zubkoff"; On 10-Mar-96 you wrote:
> > Date: Sun, 10 Mar 1996 11:10:21 -0500 (EST)
> From: Steve Thompson <stevet@bofh.1984.net>
>
> Recently, I got an active terminator for the 486 and it's been OK
> for three days, but this does not necessarily explain some of the symptoms.
> One odd fact is that I have seen the "SCSI command aborting due to timeout
> for PID xxxxxx" where xxxxxx _is_ a six-digit number. I was under the
> impression that PIDs were 15 bits.
>
> Inadequate termination can definitely lead to nasty problems, especially once
> you start boosting performance and trying to push the SCSI bus harder.

Good suggestion, was already tried here to no avail;
One system uses Brand-new micropolis fdrives and Quantum drives on a DPT PM3224
(SE Wide). The other is BusLogic 956CD (Diff. WIDE) with HP drives.
Both are terminated CORRECTLY (as per spec). READS from disk are OK, WRITEs are
a disaster. Tape Operations are particularly bad. I could panic Linux 1.2.0 wi
th
a DAT drive on a DPT with blocking factor of 1MB. Still can do it on 1.3.71 wit
h
blocking factor of 32K.

>
> The PID in question here is specific to the SCSI Command structure and bears n
o
> relationship to the process IDs attached to processes. That's one of the
> reasons I'm using a different term in my discussion.
>
> BTW, Micropolis drives suck if you bought them in the summer/fall.
>
> The 4110 sucks no matter when you bought it. I've added a blacklist feature t
o
> disable tagged queuing on these drives and any others that are just plain
> buggy.
>
> Leonard
>

Sincerely Yours,
(Sent on 03/11/96, 16:20:30)
Simon Shapiro i-Connect.Net, a Division of iConnect Corp.
Shimon@i-Connect.Net 13455 SW Allen Blvd., Suite 140 Beaverton OR 97008