From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752078Ab1IBNLJ (ORCPT ); Fri, 2 Sep 2011 09:11:09 -0400 Received: from 173-166-109-252-newengland.hfc.comcastbusiness.net ([173.166.109.252]:34135 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751806Ab1IBNLF (ORCPT ); Fri, 2 Sep 2011 09:11:05 -0400 Date: Fri, 2 Sep 2011 09:10:57 -0400 From: Christoph Hellwig To: "Ted Ts'o" , Dave Chinner , Andi Kleen , Christoph Hellwig , Daniel Ehrenberg , linux-kernel@vger.kernel.org Subject: Re: Approaches to making io_submit not block Message-ID: <20110902131057.GA7779@infradead.org> References: <20110830053231.GA1627@infradead.org> <20110831052627.GA5338@infradead.org> <20110901041848.GO32358@dastard> <20110901043947.GB7761@one.firstfloor.org> <20110901065415.GP32358@dastard> <20110902130835.GB4110@thunk.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110902130835.GB4110@thunk.org> User-Agent: Mutt/1.5.21 (2010-09-15) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 02, 2011 at 09:08:35AM -0400, Ted Ts'o wrote: > That may be true for hard drives, but PCIe attached flash can support > millions of IOP's per second --- i.e., at least hundreds of IOP's in > milliseconds. Yes, these devices are expensive, but so are the > thousand-disk RAID arrays that some people attach via XFS. :-) reading / writing to the devices is different from allocator calls. You reall do not want to do an allocator call for each of these device.