From owner-freebsd-hackers Tue Nov 12 10: 6:10 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 C631437B401; Tue, 12 Nov 2002 10:06:08 -0800 (PST) Received: from testmail.wolves.k12.mo.us (testmail.wolves.k12.mo.us [207.160.214.10]) by mx1.FreeBSD.org (Postfix) with ESMTP id 45ADC43E75; Tue, 12 Nov 2002 10:06:08 -0800 (PST) (envelope-from cdillon@wolves.k12.mo.us) Received: by testmail.wolves.k12.mo.us (Postfix, from userid 1001) id 017C81A951; Tue, 12 Nov 2002 12:06:06 -0600 (CST) Received: from localhost (localhost [127.0.0.1]) by testmail.wolves.k12.mo.us (Postfix) with ESMTP id F0B1F1A947; Tue, 12 Nov 2002 12:06:06 -0600 (CST) Date: Tue, 12 Nov 2002 12:06:06 -0600 (CST) From: Chris Dillon To: Dan Ellard Cc: freebsd-fs@FreeBSD.ORG, Subject: Re: how to control tagged queueing? In-Reply-To: Message-ID: <20021112120159.Y41695-100000@duey.wolves.k12.mo.us> 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, Dan Ellard 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] -- Chris Dillon - cdillon(at)wolves.k12.mo.us FreeBSD: The fastest and most stable server OS on the planet - Available for IA32 (Intel x86) and Alpha architectures - IA64, PowerPC, UltraSPARC, ARM, and S/390 under development - http://www.freebsd.org No trees were harmed in the composition of this message, although some electrons were mildly inconvenienced. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message