From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f72.google.com (mail-wm0-f72.google.com [74.125.82.72]) by kanga.kvack.org (Postfix) with ESMTP id BAE356B000E for ; Thu, 3 May 2018 04:46:17 -0400 (EDT) Received: by mail-wm0-f72.google.com with SMTP id w74so8767238wmw.0 for ; Thu, 03 May 2018 01:46:17 -0700 (PDT) Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com. [148.163.158.5]) by mx.google.com with ESMTPS id h2-v6si8550072edc.197.2018.05.03.01.46.16 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 03 May 2018 01:46:16 -0700 (PDT) Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w438hvJ2051576 for ; Thu, 3 May 2018 04:46:15 -0400 Received: from e06smtp12.uk.ibm.com (e06smtp12.uk.ibm.com [195.75.94.108]) by mx0b-001b2d01.pphosted.com with ESMTP id 2hqx3ujtm1-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 03 May 2018 04:46:14 -0400 Received: from localhost by e06smtp12.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 3 May 2018 09:46:11 +0100 Subject: Re: [RFC PATCH] Add /proc//numa_vamaps for numa node information References: <1525240686-13335-1-git-send-email-prakash.sangappa@oracle.com> <20180502143323.1c723ccb509c3497050a2e0a@linux-foundation.org> <2ce01d91-5fba-b1b7-2956-c8cc1853536d@intel.com> From: Anshuman Khandual Date: Thu, 3 May 2018 14:16:02 +0530 MIME-Version: 1.0 In-Reply-To: <2ce01d91-5fba-b1b7-2956-c8cc1853536d@intel.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Message-Id: <33f96879-351f-674a-ca23-43f233f4eb1d@linux.vnet.ibm.com> Sender: owner-linux-mm@kvack.org List-ID: To: Dave Hansen , Andrew Morton , Prakash Sangappa Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-api@vger.kernel.org, mhocko@suse.com, kirill.shutemov@linux.intel.com, n-horiguchi@ah.jp.nec.com, drepper@gmail.com, rientjes@google.com, Naoya Horiguchi On 05/03/2018 03:58 AM, Dave Hansen wrote: > On 05/02/2018 02:33 PM, Andrew Morton wrote: >> On Tue, 1 May 2018 22:58:06 -0700 Prakash Sangappa wrote: >>> For analysis purpose it is useful to have numa node information >>> corresponding mapped address ranges of the process. Currently >>> /proc//numa_maps provides list of numa nodes from where pages are >>> allocated per VMA of the process. This is not useful if an user needs to >>> determine which numa node the mapped pages are allocated from for a >>> particular address range. It would have helped if the numa node information >>> presented in /proc//numa_maps was broken down by VA ranges showing the >>> exact numa node from where the pages have been allocated. > > I'm finding myself a little lost in figuring out what this does. Today, > numa_maps might us that a 3-page VMA has 1 page from Node 0 and 2 pages > from Node 1. We group *entirely* by VMA: > > 1000-4000 N0=1 N1=2 > > We don't want that. We want to tell exactly where each node's memory is > despite if they are in the same VMA, like this: > > 1000-2000 N1=1 > 2000-3000 N0=1 > 3000-4000 N1=1 I am kind of wondering on a big memory system how many lines of output we might have for a large (consuming lets say 80 % of system RAM) VMA in interleave policy. Is not that a problem ?