Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754019Ab0AHTnL (ORCPT ); Fri, 8 Jan 2010 14:43:11 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753977Ab0AHTnK (ORCPT ); Fri, 8 Jan 2010 14:43:10 -0500 Received: from smtp1.linux-foundation.org ([140.211.169.13]:41502 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753941Ab0AHTnI (ORCPT ); Fri, 8 Jan 2010 14:43:08 -0500 Date: Fri, 8 Jan 2010 11:42:38 -0800 (PST) From: Linus Torvalds X-X-Sender: torvalds@localhost.localdomain To: Andi Kleen cc: Christoph Lameter , Peter Zijlstra , KAMEZAWA Hiroyuki , Minchan Kim , "Paul E. McKenney" , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "hugh.dickins" , Nick Piggin , Ingo Molnar Subject: Re: [RFC][PATCH 6/8] mm: handle_speculative_fault() In-Reply-To: Message-ID: References: <20100106115233.5621bd5e.kamezawa.hiroyu@jp.fujitsu.com> <20100106125625.b02c1b3a.kamezawa.hiroyu@jp.fujitsu.com> <1262969610.4244.36.camel@laptop> <87my0omo3n.fsf@basil.nowhere.org> <20100108192815.GB14141@basil.fritz.box> User-Agent: Alpine 2.00 (LFD 1167 2008-08-23) MIME-Version: 1.0 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: 1044 Lines: 28 On Fri, 8 Jan 2010, Linus Torvalds wrote: > > Another fact is simply that you shouldn't write your app so that it needs > to do millions of page faults per second. Side note: an app with lots of threads, and that needs to fault in lots of pages at startup time, and has performance problems, can - and should - likely use interfaces that are _designed_ for that. There's things like madvise(WILLNEED) etc, which can batch up the filling of a memory area. If you're doing a performance-sensitive application with hundreds of threads, and hundreds of gigabytes of data, you had better know about simple concepts like "batch fill", rather than whine about "oh my, my totally special-case app takes a few seconds to start because I'M A F*CKING MORON AND DID EVERYTHING WRONG". Linus -- 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/