From owner-freebsd-arch Wed Mar 21 13:30:34 2001 Delivered-To: freebsd-arch@freebsd.org Received: from critter.freebsd.dk (critter.freebsd.dk [212.242.86.163]) by hub.freebsd.org (Postfix) with ESMTP id 1CBAF37B720 for ; Wed, 21 Mar 2001 13:30:32 -0800 (PST) (envelope-from phk@critter.freebsd.dk) Received: from critter (localhost [127.0.0.1]) by critter.freebsd.dk (8.11.3/8.11.3) with ESMTP id f2LLUK189283; Wed, 21 Mar 2001 22:30:20 +0100 (CET) (envelope-from phk@critter.freebsd.dk) To: mjacob@feral.com Cc: arch@FreeBSD.ORG Subject: Re: remind me again, why is MAXPHYS only 128k ? In-Reply-To: Your message of "Wed, 21 Mar 2001 13:25:17 PST." Date: Wed, 21 Mar 2001 22:30:20 +0100 Message-ID: <89281.985210220@critter> From: Poul-Henning Kamp Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG In message , Matthew Jacob writes: > >Folks complained about some VM issues for trying to wire down a megabyte, etc. > >You sent me a suggestion as to how we could do specific device wiring w/o >increasing MAXPHYS itself. > >That said, in NetBSD I've run 1024K MAXPHYS- you just have to make sure that >the max buffer size doesn't track MAXPHYS 'coz you run out of memory rather >quick. Yeah, it's a mistake for struct buf/bio to use a fixed array of pages (b->b_pages) If we made that a ** instead we could have a variable MAXPHYS... -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk@FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message