From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752910Ab1BVBxl (ORCPT ); Mon, 21 Feb 2011 20:53:41 -0500 Received: from e4.ny.us.ibm.com ([32.97.182.144]:34187 "EHLO e4.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752098Ab1BVBxl (ORCPT ); Mon, 21 Feb 2011 20:53:41 -0500 Subject: [PATCH 0/5] fix up /proc/$pid/smaps to not split huge pages To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, Michael J Wolf , Andrea Arcangeli , akpm@osdl.org, Dave Hansen From: Dave Hansen Date: Mon, 21 Feb 2011 17:53:38 -0800 Message-Id: <20110222015338.309727CA@kernel> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Andrew, these have gone through a couple of review rounds. Can they have a spin in -mm? -- I'm working on some more reports that transparent huge pages and KSM do not play nicely together. Basically, whenever THP's are present along with KSM, there is a lot of attrition over time, and we do not see much overall progress keeping THP's around: http://sr71.net/~dave/ibm/038_System_Anonymous_Pages.png (That's Karl Rister's graph, thanks Karl!) However, I realized that we do not currently have a nice way to find out where individual THP's might be on the system. We have an overall count, but no way of telling which processes or VMAs they might be in. I started to implement this in the /proc/$pid/smaps code, but quickly realized that the lib/pagewalk.c code unconditionally splits THPs up. This set reworks that code a bit and, in the end, gives you a per-map count of the numbers of huge pages. It also makes it possible for page walks to _not_ split THPs. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with ESMTP id B4B648D0039 for ; Mon, 21 Feb 2011 20:53:40 -0500 (EST) Received: from d01relay02.pok.ibm.com (d01relay02.pok.ibm.com [9.56.227.234]) by e2.ny.us.ibm.com (8.14.4/8.13.1) with ESMTP id p1M1ZWPw030991 for ; Mon, 21 Feb 2011 20:35:32 -0500 Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by d01relay02.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p1M1rdKj479264 for ; Mon, 21 Feb 2011 20:53:39 -0500 Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1]) by d03av02.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p1M1rcWm023017 for ; Mon, 21 Feb 2011 18:53:38 -0700 Subject: [PATCH 0/5] fix up /proc/$pid/smaps to not split huge pages From: Dave Hansen Date: Mon, 21 Feb 2011 17:53:38 -0800 Message-Id: <20110222015338.309727CA@kernel> Sender: owner-linux-mm@kvack.org List-ID: To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, Michael J Wolf , Andrea Arcangeli , akpm@osdl.org, Dave Hansen Andrew, these have gone through a couple of review rounds. Can they have a spin in -mm? -- I'm working on some more reports that transparent huge pages and KSM do not play nicely together. Basically, whenever THP's are present along with KSM, there is a lot of attrition over time, and we do not see much overall progress keeping THP's around: http://sr71.net/~dave/ibm/038_System_Anonymous_Pages.png (That's Karl Rister's graph, thanks Karl!) However, I realized that we do not currently have a nice way to find out where individual THP's might be on the system. We have an overall count, but no way of telling which processes or VMAs they might be in. I started to implement this in the /proc/$pid/smaps code, but quickly realized that the lib/pagewalk.c code unconditionally splits THPs up. This set reworks that code a bit and, in the end, gives you a per-map count of the numbers of huge pages. It also makes it possible for page walks to _not_ split THPs. -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org