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Date:      Thu, 30 Mar 1995 21:29:39 -0600 (CST)
From:      bob@obiwan.pmr.com (Bob Willcox)
To:        nate@trout.sri.MT.net (Nate Williams)
Cc:        se@MI.Uni-Koeln.DE, phk@ref.tfs.com, CVS-commiters@freefall.cdrom.com, cvs-sys@freefall.cdrom.com
Subject:   Re: cvs commit: src/sys/i386/conf BOOTFLP
Message-ID:  <m0ruXP1-000300C@obiwan.pmr.com>
In-Reply-To: <199503310003.RAA08748@trout.sri.MT.net> from "Nate Williams" at Mar 30, 95 05:03:40 pm

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Nate Williams wrote:
> 
> > For this reason we considered switching on FAST SCSI from 
> > rc.local or some other startup file might be not so good an 
> > idea. But we could go back to asynch as the default in the 
> > GENERIC kernel, too ...
> 
> I think you should add a comment to the GENERIC kernel above the ncr
> driver line which explains how to make the drive use SYNC mode.  Anyone
> who builds a custom kernel will then be informed how to get SYNC mode.
> 
> IMHO, leaving the default to ASYNC is better because even broken
> hardware works with it.

Problem is, many (most?) folks will never know why their drives are
running so slow on FreeBSD.  They will just assume that the system is
slow.  The unwashed masses may not build custom kernels, but they will
likely run benchmarks!

I feel that enabling FAST synchronous negotiation should -not-
require a rebuild of the kernel.

In my experience when working on the 53C810 device driver for AIX,
none of the problems I encountered went away or got better because
I lowered the bus speed.  Originally I was requested to slow the
bus down (to 5mHz) whenever someone plugged an external cable in.
Though I did implement this behavior at first, I simply could not
find any case where fast worked and slow failed.  They either both
worked or both failed.  Eventually it will be a configuration option
on a per device basis (I don't think it yet is and I don't work on
it anymore).

My experiences and opinons only...and I never worked with any of
the Toshiba drives (though we had some broken Quantums, Conners,
Satsumas, Maxtors, ...)


-- 
Bob Willcox
bob@obiwan.pmr.com (or obiwan%bob@uunet.uu.net)
Austin, TX



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