From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761790AbZEGOi5 (ORCPT ); Thu, 7 May 2009 10:38:57 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755724AbZEGOir (ORCPT ); Thu, 7 May 2009 10:38:47 -0400 Received: from casper.infradead.org ([85.118.1.10]:38887 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756212AbZEGOiq (ORCPT ); Thu, 7 May 2009 10:38:46 -0400 Subject: Re: [PATCH -mm] vmscan: make mapped executable pages the first class citizen From: Peter Zijlstra To: Christoph Lameter Cc: Wu Fengguang , Andrew Morton , Rik van Riel , "linux-kernel@vger.kernel.org" , "tytso@mit.edu" , "linux-mm@kvack.org" , Elladan , Nick Piggin , Johannes Weiner , KOSAKI Motohiro In-Reply-To: References: <20090430072057.GA4663@eskimo.com> <20090430174536.d0f438dd.akpm@linux-foundation.org> <20090430205936.0f8b29fc@riellaptop.surriel.com> <20090430181340.6f07421d.akpm@linux-foundation.org> <20090430215034.4748e615@riellaptop.surriel.com> <20090430195439.e02edc26.akpm@linux-foundation.org> <49FB01C1.6050204@redhat.com> <20090501123541.7983a8ae.akpm@linux-foundation.org> <20090503031539.GC5702@localhost> <1241432635.7620.4732.camel@twins> <20090507121101.GB20934@localhost> <1241705702.11251.156.camel@twins> Content-Type: text/plain Content-Transfer-Encoding: 7bit Date: Thu, 07 May 2009 16:38:01 +0200 Message-Id: <1241707081.11251.160.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.26.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2009-05-07 at 10:18 -0400, Christoph Lameter wrote: > On Thu, 7 May 2009, Peter Zijlstra wrote: > > > It re-instates the young bit for PROT_EXEC pages, so that they will only > > be paged when they are really cold, or there is severe pressure. > > But they are rescanned until then. Really cold means what exactly? I do a > back up of a few hundred gigabytes and do not use firefox while the backup > is ongoing. Will the firefox pages still be in memory or not? Likely not. What this patch does is check the young bit on active_file scan, if its found to be set and the page is PROT_EXEC, put the page back on the active_file list, otherwise drop it to the inactive_file list. So if you haven't ran any firefox code, it should be gone from the active list after 2 full cycles, and from the inactive list on the first full inactive cycle after that. If you don't understand the patch, what are you complaining about, whats your point? From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with ESMTP id A86E46B004D for ; Thu, 7 May 2009 10:37:32 -0400 (EDT) Subject: Re: [PATCH -mm] vmscan: make mapped executable pages the first class citizen From: Peter Zijlstra In-Reply-To: References: <20090430072057.GA4663@eskimo.com> <20090430174536.d0f438dd.akpm@linux-foundation.org> <20090430205936.0f8b29fc@riellaptop.surriel.com> <20090430181340.6f07421d.akpm@linux-foundation.org> <20090430215034.4748e615@riellaptop.surriel.com> <20090430195439.e02edc26.akpm@linux-foundation.org> <49FB01C1.6050204@redhat.com> <20090501123541.7983a8ae.akpm@linux-foundation.org> <20090503031539.GC5702@localhost> <1241432635.7620.4732.camel@twins> <20090507121101.GB20934@localhost> <1241705702.11251.156.camel@twins> Content-Type: text/plain Content-Transfer-Encoding: 7bit Date: Thu, 07 May 2009 16:38:01 +0200 Message-Id: <1241707081.11251.160.camel@twins> Mime-Version: 1.0 Sender: owner-linux-mm@kvack.org To: Christoph Lameter Cc: Wu Fengguang , Andrew Morton , Rik van Riel , "linux-kernel@vger.kernel.org" , "tytso@mit.edu" , "linux-mm@kvack.org" , Elladan , Nick Piggin , Johannes Weiner , KOSAKI Motohiro List-ID: On Thu, 2009-05-07 at 10:18 -0400, Christoph Lameter wrote: > On Thu, 7 May 2009, Peter Zijlstra wrote: > > > It re-instates the young bit for PROT_EXEC pages, so that they will only > > be paged when they are really cold, or there is severe pressure. > > But they are rescanned until then. Really cold means what exactly? I do a > back up of a few hundred gigabytes and do not use firefox while the backup > is ongoing. Will the firefox pages still be in memory or not? Likely not. What this patch does is check the young bit on active_file scan, if its found to be set and the page is PROT_EXEC, put the page back on the active_file list, otherwise drop it to the inactive_file list. So if you haven't ran any firefox code, it should be gone from the active list after 2 full cycles, and from the inactive list on the first full inactive cycle after that. If you don't understand the patch, what are you complaining about, whats your point? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org