Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755322Ab0AFEVg (ORCPT ); Tue, 5 Jan 2010 23:21:36 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754774Ab0AFEVf (ORCPT ); Tue, 5 Jan 2010 23:21:35 -0500 Received: from smtp1.linux-foundation.org ([140.211.169.13]:40069 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754732Ab0AFEVe (ORCPT ); Tue, 5 Jan 2010 23:21:34 -0500 Date: Tue, 5 Jan 2010 20:20:56 -0800 (PST) From: Linus Torvalds X-X-Sender: torvalds@localhost.localdomain To: KAMEZAWA Hiroyuki cc: Minchan Kim , Peter Zijlstra , "Paul E. McKenney" , Peter Zijlstra , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , cl@linux-foundation.org, "hugh.dickins" , Nick Piggin , Ingo Molnar Subject: Re: [RFC][PATCH 6/8] mm: handle_speculative_fault() In-Reply-To: <20100106125625.b02c1b3a.kamezawa.hiroyu@jp.fujitsu.com> Message-ID: References: <20100104182429.833180340@chello.nl> <20100104182813.753545361@chello.nl> <20100105092559.1de8b613.kamezawa.hiroyu@jp.fujitsu.com> <28c262361001042029w4b95f226lf54a3ed6a4291a3b@mail.gmail.com> <20100105134357.4bfb4951.kamezawa.hiroyu@jp.fujitsu.com> <20100105143046.73938ea2.kamezawa.hiroyu@jp.fujitsu.com> <20100105163939.a3f146fb.kamezawa.hiroyu@jp.fujitsu.com> <20100106092212.c8766aa8.kamezawa.hiroyu@jp.fujitsu.com> <20100106115233.5621bd5e.kamezawa.hiroyu@jp.fujitsu.com> <20100106125625.b02c1b3a.kamezawa.hiroyu@jp.fujitsu.com> 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: 807 Lines: 20 On Wed, 6 Jan 2010, KAMEZAWA Hiroyuki wrote: > > > > Of course, your other load with MADV_DONTNEED seems to be horrible, and > > has some nasty spinlock issues, but that looks like a separate deal (I > > assume that load is just very hard on the pgtable lock). > > It's zone->lock, I guess. My test program avoids pgtable lock problem. Yeah, I should have looked more at your callchain. That's nasty. Much worse than the per-mm lock. I thought the page buffering would avoid the zone lock becoming a huge problem, but clearly not in this case. 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/