Skip site navigation (1)Skip section navigation (2)
Date:      31 Jan 2001 21:07:45 +0100
From:      Dag-Erling Smorgrav <des@ofug.org>
To:        Dan Nelson <dnelson@emsphone.com>
Cc:        Seigo Tanimura <tanimura@r.dl.itc.u-tokyo.ac.jp>, arch@FreeBSD.ORG
Subject:   Re: Bumping up {MAX,DFLT}*PHYS (was Re: Bumping up {MAX,DFL}*SIZ in i386)
Message-ID:  <xzphf2fo57y.fsf@flood.ping.uio.no>
In-Reply-To: Dan Nelson's message of "Wed, 31 Jan 2001 14:04:17 -0600"
References:  <vmhf2g5lrj.wl@rina.r.dl.itc.u-tokyo.ac.jp> <20010131140416.C21193@dan.emsphone.com>

next in thread | previous in thread | raw e-mail | index | archive | help
Dan Nelson <dnelson@emsphone.com> writes:
> On a similar note, is there any reason for us to have DFLTPHYS at 64k
> anymore?  With the insane interface speeds of SCSI and ATA devices
> nowadays, you can easily hit 600 I/Os per second on sequential reads
> (40MB/sec, 64K per I/O).  Would anything break if MAXPHYS/DFLTPHYS was
> bumped to say, 1mb?

I think so; we can't do DMA transfers larger than 64k (128k in word
mode) - at least for ISA devices, I don't know much about PCI.

DES
-- 
Dag-Erling Smorgrav - des@ofug.org


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-arch" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?xzphf2fo57y.fsf>