From owner-freebsd-bugs Thu Apr 17 15:40:04 1997 Return-Path: Received: (from root@localhost) by freefall.freebsd.org (8.8.5/8.8.5) id PAA11585 for bugs-outgoing; Thu, 17 Apr 1997 15:40:04 -0700 (PDT) Received: (from gnats@localhost) by freefall.freebsd.org (8.8.5/8.8.5) id PAA11576; Thu, 17 Apr 1997 15:40:02 -0700 (PDT) Date: Thu, 17 Apr 1997 15:40:02 -0700 (PDT) Message-Id: <199704172240.PAA11576@freefall.freebsd.org> To: freebsd-bugs Cc: From: Bob Bishop Subject: Re: kern/3292: Cyrix 486 performance problem Reply-To: Bob Bishop Sender: owner-bugs@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk The following reply was made to PR kern/3292; it has been noted by GNATS. From: Bob Bishop To: "Justin T. Gibbs" Cc: FreeBSD-gnats-submit@freebsd.org Subject: Re: kern/3292: Cyrix 486 performance problem Date: Thu, 17 Apr 1997 23:19:06 +0100 At 11:34 pm +0100 14/4/97, Justin T. Gibbs wrote: >Have you played around with all of the new fangled CPU options? >They're documented in lint. My guess is that your cache is disabled. You're right, this CPU needs options CYRIX_CACHE_WORKS. I've never heard of cache problems with Cyrix 486DX; except perhaps when using them on old Cyrix-unaware motherboards, and then they often won't run period. I have a machine around with a (similar IIRC) TI486DX2/80, guess I'd better check that too. On a 486DX2/80 with the cache disabled you'd need over 3 hours to build a kernel to fix it. On the evidence so far I'd say the cache should be enabled by default for Cx486; I appreciate there are other gotchas with Cx586 and Cx686. -- Bob Bishop (0118) 977 4017 international code +44 118 rb@gid.co.uk fax (0118) 989 4254 between 0800 and 1800 UK