From owner-freebsd-scsi Fri Sep 10 15:36:35 1999 Delivered-To: freebsd-scsi@freebsd.org Received: from caspian.plutotech.com (caspian.plutotech.com [206.168.67.80]) by hub.freebsd.org (Postfix) with ESMTP id 062D315E12; Fri, 10 Sep 1999 15:36:19 -0700 (PDT) (envelope-from gibbs@caspian.plutotech.com) Received: from caspian.plutotech.com (localhost [127.0.0.1]) by caspian.plutotech.com (8.9.3/8.9.1) with ESMTP id QAA03334; Fri, 10 Sep 1999 16:36:35 -0600 (MDT) (envelope-from gibbs@caspian.plutotech.com) Message-Id: <199909102236.QAA03334@caspian.plutotech.com> X-Mailer: exmh version 2.0.2 2/24/98 To: Andrew Gallatin Cc: "Justin T. Gibbs" , scsi@freebsd.org, gibbs@freebsd.org, anderson@cs.duke.edu Subject: Re: data corruption when using aic7890 In-reply-to: Your message of "Fri, 10 Sep 1999 17:49:48 EDT." <14297.30000.669959.29706@grasshopper.cs.duke.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Fri, 10 Sep 1999 16:36:35 -0600 From: "Justin T. Gibbs" Sender: owner-freebsd-scsi@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org >My tweak didn't seem to help either. The default setting seem to >be the most reliable. Should I continue to tweak this variable, or do >you have other ideas? I would continue to tweak the variable. I assume you tried setting the read threshold to MIN and the write threshold to MAX? In other words, don't start a read from host memory until the FIFO is almost empty, and don't start a write to host memory until the FIFO is almost full. The assumption here is that PCI is faster than the SCSI bus speed so we'll get the longest bursts this way. >I really appreciate your help. We've got 20 of these machines & I'd >really like to avoid having to purchase 20 scsi controllers to replace >the on-board ones. I'd like to ensure that the driver works correctly too. -- Justin To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-scsi" in the body of the message