From owner-freebsd-questions Sun Aug 4 10:12:43 2002 Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.FreeBSD.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 08C1D37B400 for ; Sun, 4 Aug 2002 10:12:40 -0700 (PDT) Received: from smtp3.southeast.rr.com (smtp3.southeast.rr.com [24.93.67.84]) by mx1.FreeBSD.org (Postfix) with ESMTP id DB4F643E42 for ; Sun, 4 Aug 2002 10:12:38 -0700 (PDT) (envelope-from bts@fake.com) Received: from mail6.nc.rr.com (fe6 [24.93.67.53]) by smtp3.southeast.rr.com (8.12.5/8.12.2) with ESMTP id g74HCRga016308; Sun, 4 Aug 2002 13:12:27 -0400 (EDT) Received: from this.is.fake.com ([66.26.254.93]) by mail6.nc.rr.com with Microsoft SMTPSVC(5.5.1877.757.75); Sun, 4 Aug 2002 13:12:38 -0400 Received: by this.is.fake.com (Postfix, from userid 111) id BBADDBB34; Sun, 4 Aug 2002 13:11:56 -0400 (EDT) Content-Type: text/plain; charset="iso-8859-1" From: "Brian T. Schellenberger" To: Nuno Teixeira , freebsd-questions@freebsd.org Subject: Re: ata_tags and write_cache question (CORRECTED) Date: Sun, 4 Aug 2002 13:11:56 -0400 User-Agent: KMail/1.4.2 References: <20020804163925.GB51994@gw.tex.bogus> <20020804165444.GC51994@gw.tex.bogus> In-Reply-To: <20020804165444.GC51994@gw.tex.bogus> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-Id: <200208041311.56345.bts@babbleon.org> Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Well, what you should *not* do is to use "plain" (untagged) write cache and softupdates at the same time, as the two together increase latency time even more, and when I briefly did that I lost work that I'd done just before shutting down, and left my file systems in a corrupt state (forced fsck on reboot). I solved the problem by disabling write caching. But in theory the tagging makes it safer. I wouldn't recommend it, but it depends on your tolerance for risk vs. speed. If you *do* do it, there are still potential latency problems. It would be wise not to do a "shutdown -p" with this setup, but rahther to do "shutdown -h" and then power off after waiting a few seconds until the disk has been quiet for a while. On Sunday 04 August 2002 12:54 pm, Nuno Teixeira wrote: | Hello to all, | | I made a mistake. | | The right question is: | | Can we use ata tags (it implies write cache) AND softupdates | simultaneosly? Or should only use this features separately? | | On Sun, Aug 04, 2002 at 05:39:25PM +0100, Nuno Teixeira wrote: | > Hello to all, | > | > I have searched at google about using ata tags and write cache on | > DTLA IBM disks but I haven't found a right answer to: | > | > Can we use ata tags and write cache simultaneosly? Or should only | > use this features separately? | > | > Thanks very much, | > | > Nuno Teixeira | > | > -- | > | > /* | > PGP fingerprint: | > C6D1 06ED EB54 A99C 6B14 6732 0A5D 810D 727D F6C6 | > */ | > | > To Unsubscribe: send mail to majordomo@FreeBSD.org | > with "unsubscribe freebsd-questions" in the body of the message -- Brian, the man from Babble-On . . . . bts@babbleon.org (personal) http://www.babbleon.org http://www.eff.org http://www.programming-freedom.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message