From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx105.postini.com [74.125.245.105]) by kanga.kvack.org (Postfix) with SMTP id C49586B0034 for ; Thu, 4 Jul 2013 05:32:14 -0400 (EDT) Date: Thu, 4 Jul 2013 10:32:11 +0100 From: Mel Gorman Subject: Re: [PATCH 12/13] mm: numa: Scan pages with elevated page_mapcount Message-ID: <20130704093211.GN1875@suse.de> References: <1372861300-9973-1-git-send-email-mgorman@suse.de> <1372861300-9973-13-git-send-email-mgorman@suse.de> <20130703184124.GD18898@dyad.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20130703184124.GD18898@dyad.programming.kicks-ass.net> Sender: owner-linux-mm@kvack.org List-ID: To: Peter Zijlstra Cc: Srikar Dronamraju , Ingo Molnar , Andrea Arcangeli , Johannes Weiner , Linux-MM , LKML On Wed, Jul 03, 2013 at 08:41:24PM +0200, Peter Zijlstra wrote: > On Wed, Jul 03, 2013 at 03:21:39PM +0100, Mel Gorman wrote: > > > Note that the patch still leaves shared, file-backed in VM_EXEC vmas in > > place guessing that these are shared library pages. Migrating them are > > likely to be of major benefit as generally the expectation would be that > > these are read-shared between caches and that iTLB and iCache pressure is > > generally low. > > I'm failing to grasp.. we don't migrate them because migrating them would > likely be beneficial? > > Missing a negative somewhere? Yes. Note that the patch does not migrate shared, file-backed within vmas marked VM_EXEC as these are generally shared library pages. Migrating such pages is not beneficial as there is an expectation they are read-shared between caches and iTLB and iCache pressure is generally low. -- Mel Gorman SUSE Labs -- 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