Path: utzoo!mnetor!uunet!unisoft!hoptoad!dasys1!manes
From: manes@dasys1.UUCP (Steve Manes)
Newsgroups: comp.unix.questions
Subject: Re: Unix (Microport) internal question
Message-ID: <2621@dasys1.UUCP>
Date: 18 Jan 88 11:40:46 GMT
References: <2788@killer.UUCP>
Reply-To: manes@dasys1.UUCP (Steve Manes)
Organization: Datamerica Systems, NYC
Lines: 30
Keywords: Unix Microport internals

In article <2788@killer.UUCP> ajohnson@killer.UUCP (Andy Johnson) writes:
>I have been running Microport's Unix V2.2 for about 7 months now
>and have encountered the messages:
>            tss fault
>            double panic tss fault
>
>I have contacted Microport on more than one occasion and asked them
>about this.  Their answer was, it shouldn't happen, but they never
>could/would tell me what it is.

They're right -- it shouldn't happen.  But I ran a multiuser BBS and had
fairly heavy UUCP traffic running on my V/AT and suffered panic attacks
at least once a week.  The last time, on Jan 2nd, fsstat completely trashed
my root file system on reboot and I'm still trying to liberate files on
/usr.  The problem seems to be in Microport's serial driver, or at least it
was rare to see tss faults unless I had a tty process active.  Microport
knows about the problem and is working on it.  For instance, you could, in
2.2, expect a tss fault if you attempted to force a steady-stream upload at
9.6 kbaud into a serial port.  2.3 seems to have reduced the liklihood of a
complete system crash but it still won't buy a 9.6 kbaud upload with large
block file protocol like Ymodem (and Xenix won't reliably do better than
4.8k either).  Experience indicates that Microport chokes on too many IRQ
requests, which also means that running something like 'doscp' with a tty
user online is risky at best.

-- 
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+ Steve Manes         Roxy Recorders, Inc.                 NYC
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