Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752280AbYCLMcx (ORCPT ); Wed, 12 Mar 2008 08:32:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751300AbYCLMcp (ORCPT ); Wed, 12 Mar 2008 08:32:45 -0400 Received: from pmx1.sophos.com ([213.31.172.16]:53901 "EHLO pmx1.sophos.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750992AbYCLMcp (ORCPT ); Wed, 12 Mar 2008 08:32:45 -0400 X-Greylist: delayed 1885 seconds by postgrey-1.27 at vger.kernel.org; Wed, 12 Mar 2008 08:32:45 EDT In-Reply-To: <200803092346.17556.phillips@phunq.net> To: Daniel Phillips Cc: linux-kernel@vger.kernel.org Subject: Re: [ANNOUNCE] Ramback: faster than a speeding bullet MIME-Version: 1.0 X-Mailer: Lotus Notes Release 6.5.5 November 30, 2005 Message-ID: From: tvrtko.ursulin@sophos.com Date: Wed, 12 Mar 2008 12:01:03 +0000 X-MIMETrack: Serialize by Router on Mercury/Servers/Sophos(Release 7.0.2FP1|January 10, 2007) at 12/03/2008 12:01:04, Serialize complete at 12/03/2008 12:01:04 Content-Type: text/plain; charset="US-ASCII" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1387 Lines: 33 linux-kernel-owner@vger.kernel.org wrote on 10/03/2008 06:46:16: > Every little factor of 25 performance increase really helps. > > Ramback is a new virtual device with the ability to back a ramdisk > by a real disk, obtaining the performance level of a ramdisk but with > the data durability of a hard disk. To work this magic, ramback needs > a little help from a UPS. In a typical test, ramback reduced a 25 > second file operation[1] to under one second including sync. Even > greater gains are possible for seek-intensive applications. What about doing a similar thing as a device mapper target? Have a look a dm-cache, I know that development of that has stopped but it doesn't mean it couldn't be ressurected. It has an advantage that it is generic (any two block devices will do) and you don't need to populate the "cache" on start-up - it happens automatically through cache misses. Another use could be a flash based disk accelerator which may be pretty popular nowadays. Tvrtko Sophos Plc, The Pentagon, Abingdon Science Park, Abingdon, OX14 3YP, United Kingdom. Company Reg No 2096520. VAT Reg No GB 348 3873 20. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/