From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965646AbXDIUrO (ORCPT ); Mon, 9 Apr 2007 16:47:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965393AbXDIUrO (ORCPT ); Mon, 9 Apr 2007 16:47:14 -0400 Received: from srv5.dvmed.net ([207.36.208.214]:57845 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965646AbXDIUrM (ORCPT ); Mon, 9 Apr 2007 16:47:12 -0400 Message-ID: <461AA64E.5040109@garzik.org> Date: Mon, 09 Apr 2007 16:47:10 -0400 From: Jeff Garzik User-Agent: Thunderbird 1.5.0.10 (X11/20070302) MIME-Version: 1.0 To: Valdis.Kletnieks@vt.edu CC: Gene Heskett , linux-kernel@vger.kernel.org, John Stoffel Subject: Re: I give up References: <200704091007.58535.gene.heskett@gmail.com> <200704091137.01336.gene.heskett@gmail.com> <17946.29660.368403.553290@smtp.charter.net> <200704091549.51805.gene.heskett@gmail.com> <461A9D42.9000008@garzik.org> <6624.1176150799@turing-police.cc.vt.edu> In-Reply-To: <6624.1176150799@turing-police.cc.vt.edu> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: -4.3 (----) X-Spam-Report: SpamAssassin version 3.1.8 on srv5.dvmed.net summary: Content analysis details: (-4.3 points, 5.0 required) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Valdis.Kletnieks@vt.edu wrote: > On Mon, 09 Apr 2007 16:08:34 EDT, Jeff Garzik said: >> With current hard drive prices (200GB @ US$55, 500GB @ US$120) you can >> just keep buying hard drives :) >> >> Surely tape price/GB is higher than hard drive price/GB... > > Erm. No. We're in the middle of installing an StorageTek SL8500 for backups, > simply because an LTO3 tape holds 300G at a price point of $100 or so. > And there's no sane way to build a half-petabyte disk farm at that price. > (And yes, our tape backup service is well into the half-petabyte range, and > will probably shoot over that as soon as the SL8500 is in production and we > deal with all the backlogged requests for backup service). > > Don't forget to factor in the cost of disk shelves, power, cooling, and all > that when you're building something to hold 2,500 200G drives. Oh. and > controllers. And machines to put the controllers in... and all the rest of it. Who says you have to keep the hard drives plugged into a machine at all times? > And remember - you *dont* want to be backing up critical data on the sort of > hard drives that cost $55 for 200G - you'll want multiple copies, probably > some RAID, etc etc. The same can be said for tape. Anyone who only has a single tape backup of critical data is an idiot. Plenty of war stories where such scenarios go awry... Jeff