From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261558AbULTQF6 (ORCPT ); Mon, 20 Dec 2004 11:05:58 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261559AbULTQF6 (ORCPT ); Mon, 20 Dec 2004 11:05:58 -0500 Received: from ylpvm29-ext.prodigy.net ([207.115.57.60]:14497 "EHLO ylpvm29.prodigy.net") by vger.kernel.org with ESMTP id S261558AbULTQFw (ORCPT ); Mon, 20 Dec 2004 11:05:52 -0500 From: David Brownell To: linux-usb-devel@lists.sourceforge.net Subject: Re: [linux-usb-devel] Re: RFC: [2.6 patch] let BLK_DEV_UB depend on EMBEDDED Date: Mon, 20 Dec 2004 08:03:44 -0800 User-Agent: KMail/1.7.1 Cc: Pete Zaitcev , Matthew Dharm , "Randy.Dunlap" , Adrian Bunk , Greg KH , linux-kernel@vger.kernel.org References: <20041220001644.GI21288@stusta.de> <200412192243.06324.david-b@pacbell.net> <20041219230603.7956d309@lembas.zaitcev.lan> In-Reply-To: <20041219230603.7956d309@lembas.zaitcev.lan> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200412200803.45190.david-b@pacbell.net> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sunday 19 December 2004 11:06 pm, Pete Zaitcev wrote: > On Sun, 19 Dec 2004 22:43:05 -0800, David Brownell wrote: > > > It also seems to mean significantly slower access (at high speed) > > for the most standard devices. That doesn't seem like a win, > > though I suspect fixing it should be as simple as switching over > > to use the USB scatterlist calls (which usb-storage uses) ... > > They do not allow asynchronous operation, last time I checked. You could add an async mode ... heck, even the hack of dedicating a kernel thread to that task ("psuedo-async" within "ub") would give much more reasonable throughput. - Dave