From owner-freebsd-questions@FreeBSD.ORG Tue Nov 4 13:57:41 2008 Return-Path: Delivered-To: questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id CAC91106568D for ; Tue, 4 Nov 2008 13:57:41 +0000 (UTC) (envelope-from jdc@koitsu.dyndns.org) Received: from QMTA07.emeryville.ca.mail.comcast.net (qmta07.emeryville.ca.mail.comcast.net [76.96.30.64]) by mx1.freebsd.org (Postfix) with ESMTP id AFD918FC2C for ; Tue, 4 Nov 2008 13:57:41 +0000 (UTC) (envelope-from jdc@koitsu.dyndns.org) Received: from OMTA01.emeryville.ca.mail.comcast.net ([76.96.30.11]) by QMTA07.emeryville.ca.mail.comcast.net with comcast id b1nZ1a01E0EPchoA71xh2d; Tue, 04 Nov 2008 13:57:41 +0000 Received: from koitsu.dyndns.org ([69.181.141.110]) by OMTA01.emeryville.ca.mail.comcast.net with comcast id b1xg1a00D2P6wsM8M1xg6D; Tue, 04 Nov 2008 13:57:40 +0000 X-Authority-Analysis: v=1.0 c=1 a=xxItaQ_nTDsA:10 a=cYCDB_SSkBgA:10 a=QycZ5dHgAAAA:8 a=QlI0C7bW_xFoicBh44YA:9 a=WpBsuXQhQeQigkVBmONf-xI_p2MA:4 a=EoioJ0NPDVgA:10 a=LY0hPdMaydYA:10 Received: by icarus.home.lan (Postfix, from userid 1000) id 2E5AFC9419; Tue, 4 Nov 2008 05:57:40 -0800 (PST) Date: Tue, 4 Nov 2008 05:57:40 -0800 From: Jeremy Chadwick To: Alex Zhang Message-ID: <20081104135740.GA49361@icarus.home.lan> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.18 (2008-05-17) Cc: Questions Subject: Re: how much memory can be support in FreeBSD system? X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 04 Nov 2008 13:57:41 -0000 On Tue, Nov 04, 2008 at 09:52:20PM +0800, Alex Zhang wrote: > I'm a new comer and want to configure a Virtual server base on UNIX. The > safe, steady and easy for maintenance is needed. > > Approximately 8GB memory will be mounted. Can anyone tell me how much memory > can be supported in FreeBSD? On 64-bit FreeBSD (what's called "amd64", but is not specific to AMD CPUs; don't let the name mislead you), you should be able to use up to 1TB of memory. On 32-bit FreeBSD (what's called i386), you can use up to 4GB (but once you surpass ~3GB, you'll only see ~3.25GB usable; this is not a FreeBSD problem, it's an x86 design thing). On 32-bit FreeBSD, you can use what's called PAE mode to increase that 4GB limit to 64GB, but there are repercussions to using PAE (read the Wikipedia article). There are also numerous drivers on FreeBSD which do not work in PAE mode. If at all possible, make sure your processor works in 64-bit mode and go with amd64. -- | Jeremy Chadwick jdc at parodius.com | | Parodius Networking http://www.parodius.com/ | | UNIX Systems Administrator Mountain View, CA, USA | | Making life hard for others since 1977. PGP: 4BD6C0CB |