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Date: Wed, 7 Jun 95 18:44:06 EDT
From: jleppek@suw2k.ess.harris.com (James Leppek)
Message-Id: <9506072244.AA21412@borg.ess.harris.com>
To: joerg_wunsch@uriah.heep.sax.de
Subject: Re: silo overflows
Cc: freebsd-hackers@freefall.cdrom.com
Sender: hackers-owner@FreeBSD.org
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The floppy is not on the adaptec, only a little used drive and an
exabyte tape drive for backups (which were not being dome).

I have changed sio.c and will see if the problem goes away with
the trigger at 8.

Since this has been seen by others when X is running could it
have something to do with the mouse events getting buffered up and
those interrupts getting served first. I seem to recall port 0 interrupts
at a higher level than 1 (irq 4 > irq 3).

just checked already had an overflow .... darn .. Oh well, only a few an
hour, guess I will try to see what happens at 115200 to see if it is
rate sensitive.

Jim

> From owner-freebsd-hackers@freefall.cdrom.com Wed Jun  7 17:56:49 1995
> From: J Wunsch <j@uriah.heep.sax.de>
> Subject: Re: silo overflows
> To: jleppek@suw2k.ess.harris.com (James Leppek)
> Date: Wed, 7 Jun 1995 23:31:45 +0200 (MET DST)
> Cc: freebsd-hackers@freefall.cdrom.com
> Reply-To: joerg_wunsch@uriah.heep.sax.de (Joerg Wunsch)
> X-Phone: +49-351-2012 669
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> 
> As James Leppek wrote:
> > 
> > The only bus hogging DMA I could think of is the 1542CF but it is
> > at the default settings which I thought were safe.
> 
> Adaptec's 154X controllers are the most `famous' bus hogs.  They do
> also cause all sort of troubles with floppy DMA operations (even
> though the FDC DMA overrun conditions are hidden from the user, but
> you will notice a _drastical_ floppy throughput drop when doing
> simultaneous operations on an AHA-154X controlled SCSI bus).
> 
> -- 
> cheers, J"org
> 
> joerg_wunsch@uriah.heep.sax.de -- http://www.sax.de/~joerg/
> Never trust an operating system you don't have sources for. ;-)
>