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To: Mostyn/Annabella <mrl@teleport.com>
cc: questions@freebsd.org
Subject: Re: bounce buffers 
In-reply-to: Your message of "Thu, 25 Apr 1996 22:47:36 PDT."
             <199604260547.WAA07623@linda.teleport.com> 
From: David Greenman <davidg@Root.COM>
Reply-To: davidg@Root.COM
Date: Thu, 25 Apr 1996 22:55:15 -0700
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>> > Under what circumstances are bounce buffers indicated?
>> 
>> In a system with an ISA busmaster and more than 16M of RAM.
>
>What about a mixed PCI ISA busmaster - e.g.
>
>Have a system with an Adaptec 2940 UW (PCI) and an
>Adaptec 1542 (ISA).
>
>Have the bounce on for the 1542 - what about its impact for
>everything else?

   It will only affect the 1542 disk transfers. The PCI transfers will not be
bounced.

-DG

David Greenman
Core-team/Principal Architect, The FreeBSD Project