From owner-freebsd-hardware Tue Jun 18 08:32:54 1996 Return-Path: owner-hardware Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id IAA03768 for hardware-outgoing; Tue, 18 Jun 1996 08:32:54 -0700 (PDT) Received: from portal.spi.net ([199.238.225.153]) by freefall.freebsd.org (8.7.5/8.7.3) with SMTP id IAA03738; Tue, 18 Jun 1996 08:32:47 -0700 (PDT) Received: from MindBender.HeadCandy.com (root@MindBender.HeadCandy.com [199.238.225.168]) by portal.spi.net (8.6.12/8.6.9) with ESMTP id IAA26603; Tue, 18 Jun 1996 08:32:38 -0700 Received: from localhost.HeadCandy.com (michaelv@localhost.HeadCandy.com [127.0.0.1]) by MindBender.HeadCandy.com (8.7.5/8.6.9) with SMTP id IAA16018; Tue, 18 Jun 1996 08:32:37 -0700 (PDT) Message-Id: <199606181532.IAA16018@MindBender.HeadCandy.com> X-Authentication-Warning: MindBender.HeadCandy.com: Host michaelv@localhost.HeadCandy.com [127.0.0.1] didn't use HELO protocol To: Alex Nash cc: bmk@fta.com, "Eloy A. Paris" , questions@freebsd.org, hardware@freebsd.org, hal@wwa.com Subject: Re: FreeBSD works with Cy486DLC processors? In-reply-to: Your message of Tue, 18 Jun 96 06:29:43 -0500. <31C69327.32639FD9@fa.tdktca.com> Date: Tue, 18 Jun 1996 08:32:28 -0700 From: "Michael L. VanLoon -- HeadCandy.com" Sender: owner-hardware@freebsd.org X-Loop: FreeBSD.org Precedence: bulk >> > I installed FreeBSD 2.1.0-RELEASE a couple of weeks ago and since then I >> > have been having programs exiting with signals 10 and 11, making my system >> > too unstable to work as a dedicated e-mail server and as a PPP to Ethernet >> > gateway. >> I had one given to me not too long ago. Mine is plagued with various >> sig 10 and 11's, same as yours. >> Here's the interesting part - disabling the internal and external cache >> makes the problem worse. >This should be fairly easy to explain: You have bad SIMMs. While your >program is running, erroneous results are returned from RAM and the >processor tries to execute them. Your program subsequently seg faults >due to an invalid instruction. This is a good candidate for the cause on the second guy's motherboard, since the problem gets worse when he turns off cache. >If your cache works properly and your >SIMMs don't, the cache can mitigate these effects since RAM accesses are >less frequent (thus missing the odd inverted bit somewhere :) ). Disable >the caches and now you will be much more likely to see a bad SIMM in action. This is typically the cause with motherboards that have 486DLC chips in them -- they're so cheap (usually just a 386 motherboard) that the cache coherency circuitry is bad to nonexistant. ----------------------------------------------------------------------------- Michael L. VanLoon michaelv@HeadCandy.com --< Free your mind and your machine -- NetBSD free un*x >-- NetBSD working ports: 386+PC, Mac 68k, Amiga, Atari 68k, HP300, Sun3, Sun4/4c/4m, DEC MIPS, DEC Alpha, PC532, VAX, MVME68k, arm32... NetBSD ports in progress: PICA, others... Roll your own Internet access -- Seattle People's Internet cooperative. If you're in the Seattle area, ask me how. -----------------------------------------------------------------------------