From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lists.gentoo.org ([140.105.134.102] helo=robin.gentoo.org) by nuthatch.gentoo.org with esmtp (Exim 4.60) (envelope-from ) id 1GDDNO-0001iM-2G for garchives@archives.gentoo.org; Wed, 16 Aug 2006 04:51:34 +0000 Received: from robin.gentoo.org (localhost [127.0.0.1]) by robin.gentoo.org (8.13.7/8.13.6) with SMTP id k7G4nT8F004177; Wed, 16 Aug 2006 04:49:29 GMT Received: from smtp.gentoo.org (smtp.gentoo.org [140.211.166.183]) by robin.gentoo.org (8.13.7/8.13.6) with ESMTP id k7G4lSZE022434 for ; Wed, 16 Aug 2006 04:47:29 GMT Received: from localhost (localhost [127.0.0.1]) by smtp.gentoo.org (Postfix) with ESMTP id DDB7F64766 for ; Wed, 16 Aug 2006 04:47:27 +0000 (UTC) Received: from smtp.gentoo.org ([127.0.0.1]) by localhost (smtp.gentoo.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 11003-16 for ; Wed, 16 Aug 2006 04:47:21 +0000 (UTC) Received: from wx-out-0506.google.com (wx-out-0506.google.com [66.249.82.234]) by smtp.gentoo.org (Postfix) with ESMTP id 2556B6466D for ; Wed, 16 Aug 2006 04:47:20 +0000 (UTC) Received: by wx-out-0506.google.com with SMTP id t13so44369wxc for ; Tue, 15 Aug 2006 21:47:20 -0700 (PDT) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:sender:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references:x-google-sender-auth; b=ESkGs/EwTkPcP6TNCOvkU9obQWfFtq7pvpwQtbuI7fbkrEeXkN8O38tr3QdPrsENfXSVNN3jL5unPaINhSQwlRtgG50RQPf2Lu1D96w85IHeJJLGfEa8Db8ASYO6LvMy6DiHmD+Xi76wuZ4WR0GKz5SCrAI8JZfgHFVZ86+E0VY= Received: by 10.70.48.15 with SMTP id v15mr346166wxv; Tue, 15 Aug 2006 21:47:20 -0700 (PDT) Received: by 10.70.110.1 with HTTP; Tue, 15 Aug 2006 21:47:20 -0700 (PDT) Message-ID: <7573e9640608152147l4497bd11o6b3a45bd746ca114@mail.gmail.com> Date: Tue, 15 Aug 2006 21:47:20 -0700 From: "Richard Fish" Sender: richard.j.fish@gmail.com To: gentoo-user@lists.gentoo.org Subject: Re: [gentoo-user] SATA tuning ? In-Reply-To: <20060816.055745.74748690.Meino.Cramer@gmx.de> Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <7573e9640608151032g4da3f3d4i54180e7b47ffda0c@mail.gmail.com> <20060815.195748.41652890.Meino.Cramer@gmx.de> <7573e9640608151941p2539bee4g500644bbfca4ef65@mail.gmail.com> <20060816.055745.74748690.Meino.Cramer@gmx.de> X-Google-Sender-Auth: eaba7f04e5c97d82 X-Virus-Scanned: amavisd-new at gentoo.org X-Spam-Status: No, score=-2.404 required=5.5 tests=[AWL=-0.082, BAYES_00=-2.599, DNS_FROM_RFC_ABUSE=0.2, TW_HD=0.077] X-Spam-Score: -2.404 X-Spam-Level: X-Archives-Salt: 800b4ad8-eef9-4021-9e1d-c9398bb001f0 X-Archives-Hash: 93983f3fdde76077c2a9d291c81be808 Moving this back to gentoo-user, as I accidentally replied off list. Meino, please don't CC me directly on replies. I'll read them on the list... On 8/15/06, Meino Christian Cramer wrote: > > > WHen doing things, which mixes higher CPU-loads with massive hd > > > utilization, things are going slow (compilation of Blender for > > > example). > > > > Ok, let's try to test that. We'll start by saturating your CPU(s). > > On one terminal start "bzip2 -9 < /dev/urandom >/dev/null". > > This commandline puts a BIG SMILE onto my face ! Yes, this is as > simple as it is genious!!! Great! Really a nice CPU barbeque ! > > > (If you > > have multiple processors, start one of these bzip2 commands on one > > terminal for each processor you have). > > > > Then on another, repeat the "hdparm -Tt /dev/sda" > > These are the results __without__ the CPU roaster: > > solfire:Mail/vim>sudo hdparm -tT /dev/sda > /dev/sda: > Timing cached reads: 2996 MB in 2.00 seconds = 1499.13 MB/sec > Timing buffered disk reads: 174 MB in 3.01 seconds = 57.79 MB/sec > > and this are the results __with__ the CPU roaster: > > solfire:/home/mccramer>sudo hdparm -Tt /dev/sda > solfire:/home/mccramer>sudo hdparm -Tt /dev/sda > /dev/sda: > Timing cached reads: 2160 MB in 2.10 seconds = 1030.12 MB/sec > Timing buffered disk reads: 174 MB in 3.03 seconds = 57.41 MB/sec > > > The chached reads dropped by ~469MByte/s. The buffered reads are > nearly the same. The buffered reads are all we care about. They are the actual reads from the disk to RAM. The cached reads is just a repeated read of the same sector of the disk, so today is really just a test of your memory bandwidth. Since we are loading memory and the CPU pretty heavily for this test, and significant drop is to be expected. So, it is not CPU utilization that is hurting your performance. You mentioned problems compiling. The most likely case I can think of is that you do not have enough memory, and are inducing the system to swap. Indeed when compiling most programs, you should see very little if any disk activity. This is particularly suspect if you have something like MAKEOPTS=-j4. Regards, -Richard -- gentoo-user@gentoo.org mailing list