From owner-freebsd-questions Sun Aug 2 22:00:14 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id WAA26104 for freebsd-questions-outgoing; Sun, 2 Aug 1998 22:00:14 -0700 (PDT) (envelope-from owner-freebsd-questions@FreeBSD.ORG) Received: from dan.emsphone.com (dan.emsphone.com [199.67.51.101]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id WAA26088 for ; Sun, 2 Aug 1998 22:00:10 -0700 (PDT) (envelope-from dan@dan.emsphone.com) Received: (from dan@localhost) by dan.emsphone.com (8.8.8/8.8.8) id XAA03756; Sun, 2 Aug 1998 23:59:55 -0500 (CDT) (envelope-from dan) Message-ID: <19980802235955.A3493@emsphone.com> Date: Sun, 2 Aug 1998 23:59:55 -0500 From: Dan Nelson To: "Henry; Michael Kenneth" , freebsd-questions@FreeBSD.ORG Subject: Re: Processor References: <199808030250.TAA15503@hub.freebsd.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.94.2i In-Reply-To: <199808030250.TAA15503@hub.freebsd.org>; from "Henry; Michael Kenneth" on Mon Aug 3 12:50:24 GMT 1998 X-OS: FreeBSD 2.2.6-STABLE Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG In the last episode (Aug 03), Henry; Michael Kenneth said: > I am preparing to make my own kernel, but I have a question about > the processor options. > > The GENERIC config file has options for 386, 486, 586, and 686 processors. > > I am using a Cyrix 6x86MX, and therefore the 686 option seems to make > the most sense, but the LINT config file says the 586 is for Pentium > processors and the 686 is for Pentium Pro processors. > > I am unsure which option to choose, and would appreciate it if someone > could give me a clue. "dmesg | grep ^CPU" will do the trick: (machine1) CPU: i486 DX2 (486-class CPU) (machine2) CPU: AMD Am5x86 Write-Through (486-class CPU) (machine3) CPU: Pentium/P54C (132.61-MHz 586-class CPU) (machine4) CPU: Pentium II (quarter-micron) (398.29-MHz 686-class CPU) Note that on machine 2, an AMD 5x86 really only supports 486 instructions. According to identcpu.c, a "Cyrix 6x86" is a souped-up 486, but a "Cyrix 6x86MX" supports 686 instructions. Looking at the kernel source though, I doubt you'll get much of a performance increase by commenting out unneeded cputypes. Just leave 486, 586, and 686 in, and you won't have to worry about recompiling your kernel if you swap CPUs. -Dan Nelson dnelson@emsphone.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message