From owner-freebsd-questions Tue Oct 27 16:40:28 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id QAA22737 for freebsd-questions-outgoing; Tue, 27 Oct 1998 16:40:28 -0800 (PST) (envelope-from owner-freebsd-questions@FreeBSD.ORG) Received: from resnet.uoregon.edu (resnet.uoregon.edu [128.223.144.32]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id QAA22716; Tue, 27 Oct 1998 16:40:25 -0800 (PST) (envelope-from dwhite@resnet.uoregon.edu) Received: from localhost (dwhite@localhost) by resnet.uoregon.edu (8.8.8/8.8.8) with ESMTP id QAA21267; Tue, 27 Oct 1998 16:39:43 -0800 (PST) (envelope-from dwhite@resnet.uoregon.edu) Date: Tue, 27 Oct 1998 16:39:42 -0800 (PST) From: Doug White To: Rob Snow cc: freebsd-questions@FreeBSD.ORG, freebsd-scsi@FreeBSD.ORG Subject: Re: CAM question 3.0-RELEASE In-Reply-To: <000d01be0170$6d5b0880$05e48486@lgc.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Tue, 27 Oct 1998, Rob Snow wrote: > I'm still debugging my problems with lockups during heavy network writing. > I've installed two 2940's and can make it fail on either controller, > eliminating my thought about some SCSI bus trash. > > Now, both of my drives seem to reset the tag queues when they go under load, > is this normal? > > My Micrapolis 3243-19 (On 2940): > tagged openings now 35 > > My Segate 39173W (On 2940UW): > tagged openings now 63 > tagged openings now 62 > ....... > tagged openings now 49 This is normal. The system tries to figure out how many tags each unit can support by experimentation and observation. Some disks are broken here and have to be quirk'd to turn off or reduce tags. > Is that supposed to happen? I'm wondering if that is an indication of a > problem. The Seagate will drop them down slowly and then all of the sudden > they plumet before it locks the system cold. Sounds like your Seagate doesn't handle tags correctly. I'd suggest checking with Seagate for a firmware upgrade, and in the meantime adding a quirk entry to /sys/cam/cam_xpt.c Search for 'quirks' and you'll find it. > Now, this happens with either local or network writes to the drives, > however, local writes do not lock the machine. It's the heavy network > writes from the wire that kill the machine. It's simply high outstanding disk transactions (which heavy writes would cause). Nothing wrong the network code, in fact it's probably a good thing that our network code can do better than the disk code :) Doug White Internet: dwhite@resnet.uoregon.edu | FreeBSD: The Power to Serve http://gladstone.uoregon.edu/~dwhite | www.freebsd.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message