From owner-freebsd-current Fri Jul 14 6:36:15 2000 Delivered-To: freebsd-current@freebsd.org Received: from smople.thehub.com.au (smople.thehub.com.au [203.143.240.10]) by hub.freebsd.org (Postfix) with ESMTP id 2D99437C87A; Fri, 14 Jul 2000 06:36:01 -0700 (PDT) (envelope-from mckay@thehub.com.au) Received: from dungeon.home (ppp228.dyn250.pacific.net.au [203.143.250.228]) by smople.thehub.com.au (8.9.3/8.9.1) with ESMTP id XAA49864; Fri, 14 Jul 2000 23:35:50 +1000 (EST) Received: from dungeon.home (localhost [127.0.0.1]) by dungeon.home (8.9.3/8.9.3) with ESMTP id XAA02458; Fri, 14 Jul 2000 23:37:57 +1000 (EST) (envelope-from mckay) Message-Id: <200007141337.XAA02458@dungeon.home> To: mjacob@feral.com Cc: wilko@FreeBSD.ORG, Stephen McKay , "Rodney W. Grimes" , "Brandon D. Valentine" , Stefan Esser , Bill Paul , freebsd-current@FreeBSD.ORG Subject: Re: dc driver and underruns (was: Strangeness with 4.0-S) References: In-Reply-To: from Matthew Jacob at "Fri, 14 Jul 2000 00:23:39 -0700" Date: Fri, 14 Jul 2000 23:37:57 +1000 From: Stephen McKay Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Friday, 14th July 2000, Matthew Jacob wrote: > >> That theory is not correct, I have seen multiple Alpha machines reporting >> buffer underruns as well. No ATA disk in sight there.. > >This has been a reported feature of the tulip chip and alphas (de driver >usually) forever forever forever. And there's no guarantee that there is just one cause. If the dc driver with BX and ZX chipsets never has an underrun, and the 2 VIA chipsets I've tried always cause underruns, there might be something we can fix. Even if we never manage to fix it on Alphas. >It's not a bug, per se, IMO. In the i386 case, there's some sort of PCI bus starvation. Maybe we can fix it. Maybe not. We can at least try to categorise it. Maybe it's as simple as a BIOS option we should tweak. Stephen. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message