From owner-freebsd-stable@FreeBSD.ORG Wed Feb 20 20:58:37 2008 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 4B28916A401 for ; Wed, 20 Feb 2008 20:58:37 +0000 (UTC) (envelope-from bright@elvis.mu.org) Received: from elvis.mu.org (elvis.mu.org [192.203.228.196]) by mx1.freebsd.org (Postfix) with ESMTP id 3747913C46E for ; Wed, 20 Feb 2008 20:58:37 +0000 (UTC) (envelope-from bright@elvis.mu.org) Received: by elvis.mu.org (Postfix, from userid 1192) id 151911A4D7E; Wed, 20 Feb 2008 12:58:37 -0800 (PST) Date: Wed, 20 Feb 2008 12:58:37 -0800 From: Alfred Perlstein To: Tom Samplonius Message-ID: <20080220205837.GX99258@elvis.mu.org> References: <20080220035752.GR99258@elvis.mu.org> <4594886.5961203490569242.JavaMail.root@ly.sdf.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4594886.5961203490569242.JavaMail.root@ly.sdf.com> User-Agent: Mutt/1.4.2.3i Cc: Kevin K , freebsd-stable@freebsd.org Subject: Re: Dual Core Xeon / i386 install w/ more than 4gb of RAM X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 20 Feb 2008 20:58:37 -0000 * Tom Samplonius [080219 23:00] wrote: > > ----- "Alfred Perlstein" wrote: > > > > > > > Does anyone have any alternative solutions that would provide a > > more > > > reliable environment other than PAE? > > > > Besideds PAE some people have mentioned running an amd64 system. > > > > One thing to consider is that PAE in 6-stable (6.3 and beyond) > > is considered very stable, so if you can't make the jump to amd64 > > system because you'd have to recompile too much, you might have luck > > updating sources to 6-stable and trying that kernel, then installing > > 6.3 userland. > > Is PAE really that stable? I thought it was fairly unpolished, mainly because PAE is seen as a weak kludge implemented by Intel because they all thought we would all be using Itanium's by now. Intel reversed their folly pretty quickly, adopted the x86-64 extensions as-is from AMD, and pushed them onto every piece of silicon they make. The 6-stable (6.3 and beyond) has been in use at Yahoo and other sites for quite some time. > I also really don't know how anyone would properly use 16GB of RAM under PAE anyways? Each process is going to limited to just under 4GB. The kernel memory space can't be bigger than 4GB either, so forget about a huge disk cache. Actually this is incorrect, the kernel can use physical memory outside of its address space as cache, so you can get more than 4GB of cache. > And is there some really stability fear about FreeBSD on x86-64? Seems just the same as i386. It's fine, people are just suggesting that the person upgrade to -stable (not stay at 6.2) and are concerned that reinstalling the machine as amd64 might be too much of a move. -Alfred