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Date: Sun, 2 Mar 1997 17:54:55 -0500 (EST)
From: Drew Derbyshire <ahd@kew.com>
Message-Id: <199703022254.RAA00722@athena.hh.kew.com>
To: questions@freebsd.org
Subject: serial port console performance issues
Sender: owner-questions@freebsd.org
X-Loop: FreeBSD.org
Precedence: bulk

On a ISA based 386/33DX machine I just brought up with 2.2-GAMMA
(2/25/97 edition), bizarre stuff is happening with the serial
console (COM1/sio0)

During boot, it initially works fine, and then just about when
syslog starts (the first or second message after the dmesg buffer
ends), output runs VERY slowly, like one character per second.
Attempts to type at the terminal when the boot messages do finish
(minutes later) usually result in a silo overflow.

I am also seeing reports of 'stray IRQ 7', which continue even
after disabling the LPT port, and pulling three of the five cards
in the unit (leaving only two modems and the two on-board serial
ports, all of which response to their properly configured IRQs)

The port runs slowly until shutdown, the final messages (syncing disk)
resumes a normal 9600 baud pace.

Suggestions?  I'm tempted to put in a PR on it ...

-ahd-