From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S268018AbUHPXDY (ORCPT ); Mon, 16 Aug 2004 19:03:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268008AbUHPXCf (ORCPT ); Mon, 16 Aug 2004 19:02:35 -0400 Received: from the-village.bc.nu ([81.2.110.252]:29669 "EHLO localhost.localdomain") by vger.kernel.org with ESMTP id S268015AbUHPXAq (ORCPT ); Mon, 16 Aug 2004 19:00:46 -0400 Subject: Re: Linux SATA RAID FAQ From: Alan Cox To: Andrew Morton Cc: ecki-news2004-05@lina.inka.de, Linux Kernel Mailing List In-Reply-To: <20040816150641.108c66a6.akpm@osdl.org> References: <1092315392.21994.52.camel@localhost.localdomain> <20040816150641.108c66a6.akpm@osdl.org> Content-Type: text/plain Content-Transfer-Encoding: 7bit Message-Id: <1092693508.21069.15.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.6 (1.4.6-2) Date: Mon, 16 Aug 2004 22:58:29 +0100 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Llu, 2004-08-16 at 23:06, Andrew Morton wrote: > I'm sitting on the vendor's driver for these cards. How does your work > differ from this? It uses the IDE layer instead of badly duplicating it in essence. > hch questioned why we need the driver at all: just put the card in JBOD > mode and use s/w raid drivers. But the thing does have an on-board CPU and > the idea is that by offloading to that, the data transits the bus just a > single time. The developers are off doing some comparative benchmarking at > present. On my set up raid1 is materially faster using their processor and raid0 is materially faster not. There are also co-existance issues with Windows dual boot setups. The PCI single copy makes a big difference on a 32bit/33Mhz plug in card. Alan