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Date: Mon, 22 Mar 2010 12:40:18 +0100
From: Gary Jennejohn <gary.jennejohn@freenet.de>
To: Alexander Motin <mav@FreeBSD.org>
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Cc: Scott Long <scottl@samsco.org>,
	FreeBSD-Current <freebsd-current@freebsd.org>, freebsd-arch@freebsd.org
Subject: Re: Increasing MAXPHYS
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On Sun, 21 Mar 2010 19:03:56 +0200
Alexander Motin <mav@FreeBSD.org> wrote:

> Scott Long wrote:
> > Are there non-CAM drivers that look at MAXPHYS, or that silently assume that
> > MAXPHYS will never be more than 128k?
> 
> That is a question.
> 

I only did a quick&dirty grep looking for MAXPHYS in /sys.

Some drivers redefine MAXPHYS to be 512KiB.  Some use their own local
MAXPHYS which is usually 128KiB.

Some look at MAXPHYS to figure out other things; the details escape me.

There's one driver which actually uses 100*MAXPHYS for something, but I
didn't check the details.

Lots of them were non-CAM drivers AFAICT.

--
Gary Jennejohn