From owner-freebsd-scsi Mon Oct 25 2:59:13 1999 Delivered-To: freebsd-scsi@freebsd.org Received: from chuggalug.clues.com (chuggalug.clues.com [194.217.82.22]) by hub.freebsd.org (Postfix) with ESMTP id 1DE2115104 for ; Mon, 25 Oct 1999 02:59:06 -0700 (PDT) (envelope-from geoffb@chuggalug.clues.com) Received: (from geoffb@localhost) by chuggalug.clues.com (8.9.3/8.9.3) id KAA91369; Mon, 25 Oct 1999 10:58:47 +0100 (BST) (envelope-from geoffb) Date: Mon, 25 Oct 1999 10:58:47 +0100 From: Geoff Buckingham To: Michael Sinz Cc: Gerard Roudier , Mike Sinz , Randell Jesup , "scsi@FreeBSD.ORG" Subject: Re: FreeBSD 3.2 / Slow SCSI Dell PowerEdge 4300 Message-ID: <19991025105847.A91296@chuggalug.clues.com> References: <199910201401.KAA25925@vixen.sinz.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.95.4i In-Reply-To: <199910201401.KAA25925@vixen.sinz.org>; from Michael Sinz on Wed, Oct 20, 1999 at 10:01:46AM -0400 Sender: owner-freebsd-scsi@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Wed, Oct 20, 1999 at 10:01:46AM -0400, Michael Sinz wrote: > > IMHO: > For a general purpose server, one must assume that the special case of > the I/O working out to be single threaded will not happen. Multiple things > will be going on and the working set will be larger than the cache size. > A bit of overhead added to the "simple" cases will make the general > operation better. Benchmarks, however, may well show this as slower > since some extra overhead had to be added. Benchmarks would need to > become much more complex in order to show the real benefit or lack of > benefit for any one technique. > Which brings us back to the question as to wether or not disabling TAGs for WDE * is the correct thing to do? IMHO it is not. -- GeoffB To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-scsi" in the body of the message