From owner-freebsd-hackers Tue Nov 12 14: 3:51 2002 Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 35BC437B401; Tue, 12 Nov 2002 14:03:50 -0800 (PST) Received: from mail.eecs.harvard.edu (bowser.eecs.harvard.edu [140.247.60.24]) by mx1.FreeBSD.org (Postfix) with ESMTP id AC02543E4A; Tue, 12 Nov 2002 14:03:49 -0800 (PST) (envelope-from ellard@eecs.harvard.edu) Received: by mail.eecs.harvard.edu (Postfix, from userid 465) id 58C5454C6EE; Tue, 12 Nov 2002 17:03:43 -0500 (EST) Received: from localhost (localhost [127.0.0.1]) by mail.eecs.harvard.edu (Postfix) with ESMTP id 404B354C630; Tue, 12 Nov 2002 17:03:43 -0500 (EST) Date: Tue, 12 Nov 2002 17:03:43 -0500 (EST) From: Dan Ellard To: Chris Dillon Cc: freebsd-fs@FreeBSD.ORG, Subject: Re: how to control tagged queueing? In-Reply-To: <20021112120159.Y41695-100000@duey.wolves.k12.mo.us> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Tue, 12 Nov 2002, Chris Dillon wrote: > > I'm experimenting with the effects of SCSI tagged queueing on file > > system performance. Is there any kind of global toggle somewhere in > > the kernel to turn tagged queueing on and off, and/or knob to limit > > the number of outstanding tags? Tagged queue management all seems > > to be done at the device level, and I haven't found hooks for > > controlling it at a higher level (but I thought I'd ask before > > running off to write something). > > > > I'm running 4.6.2p4, in case things have changed. (If there's a > > nicer interface in 4.7, I'll install it immediately!) > > man camcontrol > > Specifically: > > camcontrol tags [device id] [generic args] [-N tags] [-q] [-v] > camcontrol negotiate [device id] [generic args] [-T enable|disable] Thanks, that's exactly what I needed. And thanks to the other people who have responded! -Dan To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message