From owner-freebsd-hackers Wed Oct 30 21:53:10 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 8EE0137B401 for ; Wed, 30 Oct 2002 21:53:09 -0800 (PST) Received: from HAL9000.homeunix.com (12-232-220-15.client.attbi.com [12.232.220.15]) by mx1.FreeBSD.org (Postfix) with ESMTP id ED5C043E4A for ; Wed, 30 Oct 2002 21:53:08 -0800 (PST) (envelope-from dschultz@uclink.Berkeley.EDU) Received: from HAL9000.homeunix.com (localhost [127.0.0.1]) by HAL9000.homeunix.com (8.12.6/8.12.5) with ESMTP id g9V5r5Tx026802; Wed, 30 Oct 2002 21:53:05 -0800 (PST) (envelope-from dschultz@uclink.Berkeley.EDU) Received: (from das@localhost) by HAL9000.homeunix.com (8.12.6/8.12.5/Submit) id g9V5qqWF026801; Wed, 30 Oct 2002 21:52:52 -0800 (PST) (envelope-from dschultz@uclink.Berkeley.EDU) Date: Wed, 30 Oct 2002 21:52:52 -0800 From: David Schultz To: Peter Wemm Cc: "Daniel O'Connor" , Chuck Robey , Kenneth Culver , "Wilkinson, Alex" , hackers@FreeBSD.ORG Subject: Re: [hardware] Tagged Command Queuing or Larger Cache ? Message-ID: <20021031055252.GB26692@HAL9000.homeunix.com> Mail-Followup-To: Peter Wemm , Daniel O'Connor , Chuck Robey , Kenneth Culver , "Wilkinson, Alex" , hackers@FreeBSD.ORG References: <20021029103133.GA18812@HAL9000.homeunix.com> <20021030012824.8E54B2A88D@canning.wemm.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20021030012824.8E54B2A88D@canning.wemm.org> 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 Thus spake Peter Wemm : > > > Actually, not even then. Modern IDE drives only write entire tracks at a > > > time. If you modify a single sector, then the drive has to read the entire > > > track into the buffer, in-place edit the sector, and then rewrite the entir > e > > > track. [...] > ie: if writing to every 10th or 20th (or whatever) sector is just as slow > as writing to every sector with write caching turned off, then you have a > track-write drive. This is because every single sector write causes the > entire track to be written. I remember you mentioning this trick the last time this topic came up. I was hoping someone had the results of running this test on some actual drives. ;-) Another strategy, I suppose, would be to look at which patents the drives claim to use. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message