From owner-freebsd-questions@FreeBSD.ORG Wed Jan 14 20:18:45 2009 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 321B6106564A for ; Wed, 14 Jan 2009 20:18:45 +0000 (UTC) (envelope-from cswiger@mac.com) Received: from mail-out3.apple.com (mail-out3.apple.com [17.254.13.22]) by mx1.freebsd.org (Postfix) with ESMTP id 179B98FC0C for ; Wed, 14 Jan 2009 20:18:45 +0000 (UTC) (envelope-from cswiger@mac.com) Received: from relay14.apple.com (relay14.apple.com [17.128.113.52]) by mail-out3.apple.com (Postfix) with ESMTP id 026F84C6C3C5; Wed, 14 Jan 2009 12:18:45 -0800 (PST) Received: from relay14.apple.com (unknown [127.0.0.1]) by relay14.apple.com (Symantec Brightmail Gateway) with ESMTP id D9D2728083; Wed, 14 Jan 2009 12:18:44 -0800 (PST) X-AuditID: 11807134-a4052bb000000ff0-fa-496e48a47edd Received: from cswiger1.apple.com (cswiger1.apple.com [17.227.140.124]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) by relay14.apple.com (Apple SCV relay) with ESMTP id AFA2328087; Wed, 14 Jan 2009 12:18:44 -0800 (PST) Message-Id: From: Chuck Swiger To: Ewald Jenisch In-Reply-To: <20090114181522.GB4487@aurora.oekb.co.at> Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (Apple Message framework v930.3) Date: Wed, 14 Jan 2009 12:18:44 -0800 References: <496E06D1.2070706@gmail.com> <20090114181522.GB4487@aurora.oekb.co.at> X-Mailer: Apple Mail (2.930.3) X-Brightmail-Tracker: AAAAAA== Cc: icemaca , freebsd-questions@freebsd.org Subject: Re: kernel configuration 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: Wed, 14 Jan 2009 20:18:45 -0000 On Jan 14, 2009, at 10:15 AM, Ewald Jenisch wrote: > On Wed, Jan 14, 2009 at 04:37:53PM +0100, icemaca wrote: >> >> this i386 version has >> >> cpu I486_CPU >> cpu I586_CPU >> cpu I686_CPU >> > > Basically you can comment all but I686_CPU since the others are for > earlier x86 architectures. While it is true that you can comment out all but i686 and get a working kernel, you will experience reduced performance. There are a number of low-level assembly routines (cf sys/i386/i386/support.s such as i586_bcopy) that are conditionalized off of I586_CPU only, even though they provide an advantage on i686 platforms also. -- -Chuck