From owner-freebsd-current@FreeBSD.ORG Sat May 10 12:21:22 2003 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 5BA6E37B401 for ; Sat, 10 May 2003 12:21:22 -0700 (PDT) Received: from stork.mail.pas.earthlink.net (stork.mail.pas.earthlink.net [207.217.120.188]) by mx1.FreeBSD.org (Postfix) with ESMTP id 9677043FE0 for ; Sat, 10 May 2003 12:21:21 -0700 (PDT) (envelope-from tlambert2@mindspring.com) Received: from pool0084.cvx40-bradley.dialup.earthlink.net ([216.244.42.84] helo=mindspring.com) by stork.mail.pas.earthlink.net with asmtp (SSLv3:RC4-MD5:128) (Exim 3.33 #1) id 19EZuI-00062Z-00; Sat, 10 May 2003 12:21:19 -0700 Message-ID: <3EBD50D7.88A78B48@mindspring.com> Date: Sat, 10 May 2003 12:19:51 -0700 From: Terry Lambert X-Mailer: Mozilla 4.79 [en] (Win98; U) X-Accept-Language: en MIME-Version: 1.0 To: Heiko Schaefer References: <3EBC6C6A.1040602@myrealbox.com> <20030510130934.R93229@daneel.foundation.hs> <20030510203854.E93229@daneel.foundation.hs> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-ELNK-Trace: b1a02af9316fbb217a47c185c03b154d40683398e744b8a458bed8b69e3e694e2a4f180c2c91d21c2601a10902912494350badd9bab72f9c350badd9bab72f9c cc: freebsd-current@freebsd.org Subject: Re: data corruption with DISABLE_PSE+DISABLE_PG_G: unrelated X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 10 May 2003 19:21:22 -0000 Heiko Schaefer wrote: > i'm sorry, my mail was probably a bit confusing. > since it has been pointed out to me, i am running -current kernels with > > options DISABLE_PSE > options DISABLE_PG_G > > enabled. > > what i am asking myself: > is there any chance that i still get any data corruption because of the > issues that you write about in some configuration ?! No. Not with thouse flags set. If you are getting data corruption with the flags set, then you have some other problem, most likely hardware. > because with the 512mb (ddr) ram (which might or might not be defective) i > get data corruption, while with another 256mb (sdr) ram, i apparently > don't. At Whistle, we had a number of issues with matched simms; the simms from one manufacturer were not good vs. another, supposedly identically rated part. There's also the possibility that the RAM speed is too slow for your FSB speed. You should be careful here, because not all motherboards are able to detect this mismatch. Another less common problem with RAM is that the chipset you are using can delay referesh cycles under interrupt load, if it is programmed incorrectly. We saw this in the InterJet II with the Cyrix MediaGX chipset, which has a nasty DMA transfer bug, unless it's programmed *just so* by the BIOS. Doug Ambrisko can tell you more about the RAM problem, and Julian Elisher is the guy who rewrote the BIOS settings to program the Cyrix chipset correctly for us. Both of them are on these mailing lists, but probably not reading this thread. You may also want to try a different or bigger power supply; I've seen undervoltage and underrated power supplies cause this problem, as well, when they functioned fine with less RAM. It could also be cooling, inside the case. More RAM = more heat. Finally, I've personally seen problems when using SIMMs with gold connectors instead of tin; yeah, that's counter intuitive. This is "looking for zebras" territory, at this point, though, so take my speculations with a grain of salt. > so far i had the impression that my test (copying >30gb of checksummed > data between disks) shows these problems rather reliably. It's something other than the CPU bug; sorry. Please ignore the rest of the CPU related information to which you responded; more memory, etc., won't help you out of this one... -- Terry