From owner-freebsd-arch@FreeBSD.ORG Sat Jul 4 19:15:07 2009 Return-Path: Delivered-To: freebsd-arch@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id BB5631065674 for ; Sat, 4 Jul 2009 19:15:07 +0000 (UTC) (envelope-from mav@FreeBSD.org) Received: from cmail.optima.ua (cmail.optima.ua [195.248.191.121]) by mx1.freebsd.org (Postfix) with ESMTP id 449708FC14 for ; Sat, 4 Jul 2009 19:15:06 +0000 (UTC) (envelope-from mav@FreeBSD.org) Received: from [212.86.226.226] (account mav@alkar.net HELO mavbook.mavhome.dp.ua) by cmail.optima.ua (CommuniGate Pro SMTP 5.2.9) with ESMTPSA id 247655131 for freebsd-arch@freebsd.org; Sat, 04 Jul 2009 22:15:03 +0300 Message-ID: <4A4FAA2D.3020409@FreeBSD.org> Date: Sat, 04 Jul 2009 22:14:53 +0300 From: Alexander Motin User-Agent: Thunderbird 2.0.0.21 (X11/20090405) MIME-Version: 1.0 To: freebsd-arch@freebsd.org Content-Type: text/plain; charset=KOI8-R; format=flowed Content-Transfer-Encoding: 7bit Subject: DFLTPHYS vs MAXPHYS X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 04 Jul 2009 19:15:08 -0000 Hi. Can somebody explain me a difference between DFLTPHYS and MAXPHYS constants? As I understand, the last one is a maximal amount of memory, that can be mapped to the kernel, or passed to the hardware drivers. But why then DFLTPHYS is used in so many places and what does it mean? Isn't it a time to review their values for increasing? 64KB looks funny, comparing to modern memory sizes and data rates. It just increases interrupt rates, but I don't think it really need to be so small to improve interactivity now. -- Alexander Motin