From owner-cvs-src@FreeBSD.ORG Sun Mar 30 13:38:00 2003 Return-Path: Delivered-To: cvs-src@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 4659537B48A for ; Sun, 30 Mar 2003 13:37:58 -0800 (PST) Received: from relay.pair.com (relay.pair.com [209.68.1.20]) by mx1.FreeBSD.org (Postfix) with SMTP id D092744154 for ; Sun, 30 Mar 2003 13:34:44 -0800 (PST) (envelope-from silby@silby.com) Received: (qmail 32933 invoked from network); 30 Mar 2003 21:34:23 -0000 Received: from niwun.pair.com (HELO localhost) (209.68.2.70) by relay.pair.com with SMTP; 30 Mar 2003 21:34:23 -0000 X-pair-Authenticated: 209.68.2.70 Date: Sun, 30 Mar 2003 15:30:52 -0600 (CST) From: Mike Silbersack To: Jake Burkholder In-Reply-To: <20030330201113.GA32298@locore.ca> Message-ID: <20030330152920.D6586@odysseus.silby.com> References: <200303300524.h2U5Ora7061852@repoman.freebsd.org> <20030330061301.GC21973@locore.ca> <20030330070723.GE21973@locore.ca> <20030330012410.I3292@odysseus.silby.com> <20030330201113.GA32298@locore.ca> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII cc: cvs-src@FreeBSD.org cc: src-committers@FreeBSD.org cc: cvs-all@FreeBSD.org Subject: Re: HEADS UP Re: cvs commit: src/sys/conf options.i386 src/sys/i386/i386 bios.c locore.s machdep.c mpboot.s pmap.c vm86bios.s vm_machdep.c src/sys/i386/include _types.h bus_at386.h param.h pmap. X-BeenThere: cvs-src@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: CVS commit messages for the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 30 Mar 2003 21:38:10 -0000 On Sun, 30 Mar 2003, Jake Burkholder wrote: > > Do these changes allow something like a 3G KVA space without shrinking > > processes address spaces? > > No, it doesn't make the virtual address space any bigger, it just allows > more physical memory. This is a bit of a problem because the tunables that > are based on physical memory size don't scale well past 4G of ram, its easy > to end up with may too many vnodes. Is it practically possible with PAE and busdma'd drivers that such a configuration could work? > > it also be coaxed into acting in such a manner than busdma is _required_, > > so that a 256MB i386 box can be used to see if a driver is busdma > > compliant? > > Not really. The best way is to buy a sparc :). I suppose that you could > create your dma tags such that busdma thinks it needs to bounce, this would > at least test that you've got the right bus_dmamap_syncs. ie set lowaddr to > below the highest physical address in your machine. I'll give that a shot if I try to busdma a driver, thanks. Mike "Silby" Silbersack