From owner-freebsd-questions Tue Sep 18 6:13:53 2001 Delivered-To: freebsd-questions@freebsd.org Received: from mailrelay3.inwind.it (mailrelay3.inwind.it [212.141.54.103]) by hub.freebsd.org (Postfix) with ESMTP id 4D9F337B403 for ; Tue, 18 Sep 2001 06:13:44 -0700 (PDT) Received: from [62.98.224.180] (62.98.224.180) by mailrelay3.inwind.it (5.5.029) id 3BA608A100069310 for freebsd-questions@freebsd.org; Tue, 18 Sep 2001 15:13:41 +0200 Received: (qmail 1386 invoked by uid 1000); 18 Sep 2001 13:12:20 -0000 Date: Tue, 18 Sep 2001 15:12:19 +0200 From: Francesco Casadei To: Mike Meyer Cc: freebsd-questions mailing list Subject: Re: soft updates Message-ID: <20010918151219.A1300@goku.kasby> Mail-Followup-To: Mike Meyer , freebsd-questions mailing list References: <89370727@toto.iv> <15270.56819.636304.261065@guru.mired.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-md5; protocol="application/pgp-signature"; boundary="yrj/dFKFPuw6o+aM" Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <15270.56819.636304.261065@guru.mired.org>; from mwm@mired.org on Tue, Sep 18, 2001 at 12:38:59AM -0500 X-Operating-System: FreeBSD 4.4-RC i386 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 --yrj/dFKFPuw6o+aM Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Sep 18, 2001 at 12:38:59AM -0500, Mike Meyer wrote: > Brian T.Schellenberger types: > > On Sunday 16 September 2001 20:53, Nathan Mace wrote: > > > basically what i'm asking is is it stable? and how much of a perform= ance > > > gain am i gonna see? thanks > >=20 > > "Yes," and "a lot", respectively, but you *must* turn off write-cache o= n your=20 > > disk if you are going to use soft updates. >=20 > Only for IDE drives. SCSI provides features that let you use > write-cache safely - if the driver you are using supports the > feature. Check the driver manual page for "tagged queuing". If the > driver supports that, you can turn write caching on for the SCSI > drives attached to it. >=20 > IDE disks that support tagged queuing are coming and the ATA driver > supports them, but the most recent report I have says they aren't very > reliable. >=20 > -- > Mike Meyer http://www.mired.org/home/mwm/ > Q: How do you make the gods laugh? A: Tell them your plans. >=20 > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-questions" in the body of the message >=20 > end of the original message =46rom ata(4) manpage: [...] hw.ata.wc set to 1 to enable Write Caching, 0 to disable (default is enabled) (WARNING might cause data loss on power failures) hw.ata.tags set to 1 to enable Tagged Queuing support (default is disabled) (only = IBM DPTA and DTLA drives support that) [...] IBM IC35L0[246]0AVER07 drives support Tagged Queuing and Write Caching. Does this mean that I can safely set hw.ata.wc=3D1 and hw.ata.tags=3D1 with soft= updates enabled without going into consistency troubles? What "recent report" are you referring to? Do you know of reliablity issues with IBM drives with WC and TQ enabled? =20 Francesco Casadei --=20 You can download my public key from http://digilander.iol.it/fcasadei/ or retrieve it from a keyserver (pgpkeys.mit.edu, wwwkeys.pgp.net, ...) Key fingerprint is: 1671 9A23 ACB4 520A E7EE 00B0 7EC3 375F 164E B17B --yrj/dFKFPuw6o+aM Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.6 (FreeBSD) Comment: For info see http://www.gnupg.org iD8DBQE7p0gzfsM3XxZOsXsRAoGUAJ9YUj3I1fOW5T3Y+uS1aZN7/J+TigCg7rrv xHVkcp3H/q9hvuFX8cHSx2o= =6pVf -----END PGP SIGNATURE----- --yrj/dFKFPuw6o+aM-- To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message