From owner-freebsd-questions Thu Aug 30 1: 0:58 2001 Delivered-To: freebsd-questions@freebsd.org Received: from guru.mired.org (okc-94-248-46.mmcable.com [24.94.248.46]) by hub.freebsd.org (Postfix) with SMTP id 2EF0937B406 for ; Thu, 30 Aug 2001 01:00:54 -0700 (PDT) (envelope-from mwm@mired.org) Received: (qmail 1320 invoked by uid 100); 30 Aug 2001 08:00:47 -0000 From: Mike Meyer MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15245.62127.417241.42347@guru.mired.org> Date: Thu, 30 Aug 2001 03:00:47 -0500 To: Trevin Chow Cc: Mike Meyer , Subject: Re: Performance tuning and adding RAM In-Reply-To: <20010830004542.A80091-100000@benny.geektank.org> References: <15245.52453.614096.245669@guru.mired.org> <20010830004542.A80091-100000@benny.geektank.org> X-Mailer: VM 6.90 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid X-face: "5Mnwy%?j>IIV\)A=):rjWL~NB2aH[}Yq8Z=u~vJ`"(,&SiLvbbz2W`;h9L,Yg`+vb1>RG% *h+%X^n0EZd>TM8_IB;a8F?(Fb"lw'IgCoyM.[Lg#r\ 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 Trevin Chow types: > On Thu, 30 Aug 2001, Mike Meyer wrote: > > > For IDE drives, you disable this by setting the sysctl hw.ata.wc to 0, > > but it has to be done from the boot loader at boot time. If you are > > running 4.3-RELEASE, it's set off by default. If you're running > > something prior to 4.3-RELEASE, you may not be able to set it at > > all. The drive manufacturer may provide a DOS utility that will let > > you turn it off as well. > > > > If you are using SCSI disks, you can use the camcontrol modepage > > command to check and disable it. It's the WCE value on page 8; use > > "camcontrol modepage daX -m 8 -e" to start an editor, change the 1 to > > a 0, and then exit. > What will provide a "bigger" performance boost? Soft updates or IDE Cache > (hw.ata.wc)? Oh, leaving the disk caching enabled is definitely faster. After all, it's sort of like running a RAM disk through a slow interface. If you're going to do that, mount your file systems async buy a UPS, and make more frequent backups. http://www.mired.org/home/mwm/ Independent WWW/Perforce/FreeBSD/Unix consultant, email for more information. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message