From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id AD47FC433EF for ; Wed, 27 Apr 2022 06:56:54 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 39D336B0073; Wed, 27 Apr 2022 02:56:54 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 34CA66B0075; Wed, 27 Apr 2022 02:56:54 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 23BBD6B0078; Wed, 27 Apr 2022 02:56:54 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.a.hostedemail.com [64.99.140.24]) by kanga.kvack.org (Postfix) with ESMTP id 12F976B0073 for ; Wed, 27 Apr 2022 02:56:54 -0400 (EDT) Received: from smtpin05.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay11.hostedemail.com (Postfix) with ESMTP id D396581C2C for ; Wed, 27 Apr 2022 06:56:53 +0000 (UTC) X-FDA: 79401751506.05.8B3D6D8 Received: from out199-13.us.a.mail.aliyun.com (out199-13.us.a.mail.aliyun.com [47.90.199.13]) by imf31.hostedemail.com (Postfix) with ESMTP id 46F8920049 for ; Wed, 27 Apr 2022 06:56:42 +0000 (UTC) X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R181e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04357;MF=rongwei.wang@linux.alibaba.com;NM=1;PH=DS;RN=17;SR=0;TI=SMTPD_---0VBRXa0n_1651042577; Received: from 30.240.99.9(mailfrom:rongwei.wang@linux.alibaba.com fp:SMTPD_---0VBRXa0n_1651042577) by smtp.aliyun-inc.com(127.0.0.1); Wed, 27 Apr 2022 14:56:19 +0800 Message-ID: Date: Wed, 27 Apr 2022 14:56:16 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:100.0) Gecko/20100101 Thunderbird/100.0 Subject: Re: DAMON VA regions don't split on an large Android APP Content-Language: en-US To: Barry Song <21cnbao@gmail.com>, sj@kernel.org, Andrew Morton , Linux-MM , LKML Cc: Matthew Wilcox , shuah@kernel.org, brendanhiggins@google.com, foersleo@amazon.de, sieberf@amazon.com, Shakeel Butt , sjpark@amazon.de, tuhailong@gmail.com, Song Jiang , =?UTF-8?B?5byg6K+X5piOKFNpbW9uIFpoYW5nKQ==?= , =?UTF-8?B?5p2O5Z+56ZSLKHdpbmsp?= , xhao@linux.alibaba.com References: From: Rongwei Wang In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 46F8920049 X-Stat-Signature: k68ukot91d9ue6fsk97uxuzxi4c5zjzr X-Rspam-User: Authentication-Results: imf31.hostedemail.com; dkim=none; spf=pass (imf31.hostedemail.com: domain of rongwei.wang@linux.alibaba.com designates 47.90.199.13 as permitted sender) smtp.mailfrom=rongwei.wang@linux.alibaba.com; dmarc=pass (policy=none) header.from=alibaba.com X-HE-Tag: 1651042602-670483 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000078, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 4/27/22 7:19 AM, Barry Song wrote: > Hi SeongJae & Andrew, > (also Cc-ed main damon developers) > On an Android phone, I tried to use the DAMON vaddr monitor and found > that vaddr regions don't split well on large Android Apps though > everything works well on native Apps. > > I have tried the below two cases on an Android phone with 12GB memory > and snapdragon 888 CPU. > 1. a native program with small memory working set as below, > #define size (1024*1024*100) > main() > { > volatile int *p = malloc(size); > memset(p, 0x55, size); > > while(1) { > int i; > for (i = 0; i < size / 4; i++) > (void)*(p + i); > usleep(1000); > > for (i = 0; i < size / 16; i++) > (void)*(p + i); > usleep(1000); > > } > } > For this application, the Damon vaddr monitor works very well. > I have modified monitor.py in the damo userspace tool a little bit to > show the raw data getting from the kernel. > Regions can split decently on this kind of applications, a typical raw > data is as below, > > monitoring_start: 2.224 s > monitoring_end: 2.329 s > monitoring_duration: 104.336 ms > target_id: 0 > nr_regions: 24 > 005fb37b2000-005fb734a000( 59.594 MiB): 0 > 005fb734a000-005fbaf95000( 60.293 MiB): 0 > 005fbaf95000-005fbec0b000( 60.461 MiB): 0 > 005fbec0b000-005fc2910000( 61.020 MiB): 0 > 005fc2910000-005fc6769000( 62.348 MiB): 0 > 005fc6769000-005fca33f000( 59.836 MiB): 0 > 005fca33f000-005fcdc8b000( 57.297 MiB): 0 > 005fcdc8b000-005fd115a000( 52.809 MiB): 0 > 005fd115a000-005fd45bd000( 52.387 MiB): 0 > 007661c59000-007661ee4000( 2.543 MiB): 2 > 007661ee4000-0076623e4000( 5.000 MiB): 3 > 0076623e4000-007662837000( 4.324 MiB): 2 > 007662837000-0076630f1000( 8.727 MiB): 3 > 0076630f1000-007663494000( 3.637 MiB): 2 > 007663494000-007663753000( 2.746 MiB): 1 > 007663753000-007664251000( 10.992 MiB): 3 > 007664251000-0076666fd000( 36.672 MiB): 2 > 0076666fd000-007666e73000( 7.461 MiB): 1 > 007666e73000-007667c89000( 14.086 MiB): 2 > 007667c89000-007667f97000( 3.055 MiB): 0 > 007667f97000-007668112000( 1.480 MiB): 1 > 007668112000-00766820f000(1012.000 KiB): 0 > 007ff27b7000-007ff27d6000( 124.000 KiB): 0 > 007ff27d6000-007ff27d8000( 8.000 KiB): 8 > > 2. a large Android app like Asphalt 9 > For this case, basically regions can't split very well, but monitor > works on small vma: > > monitoring_start: 2.220 s > monitoring_end: 2.318 s > monitoring_duration: 98.576 ms > target_id: 0 > nr_regions: 15 > 000012c00000-0001c301e000( 6.754 GiB): 0 > 0001c301e000-000371b6c000( 6.730 GiB): 0 > 000371b6c000-000400000000( 2.223 GiB): 0 > 005c6759d000-005c675a2000( 20.000 KiB): 0 > 005c675a2000-005c675a3000( 4.000 KiB): 3 > 005c675a3000-005c675a7000( 16.000 KiB): 0 > 0072f1e14000-0074928d4000( 6.510 GiB): 0 > 0074928d4000-00763c71f000( 6.655 GiB): 0 > 00763c71f000-0077e863e000( 6.687 GiB): 0 > 0077e863e000-00798e214000( 6.590 GiB): 0 > 00798e214000-007b0e48a000( 6.002 GiB): 0 > 007b0e48a000-007c62f00000( 5.323 GiB): 0 > 007c62f00000-007defb19000( 6.199 GiB): 0 > 007defb19000-007f794ef000( 6.150 GiB): 0 > 007f794ef000-007fe8f53000( 1.745 GiB): 0 > > As you can see, we have some regions which are very very big and they > are losing the chance to be splitted. But > Damon can still monitor memory access for those small VMA areas very well like: > 005c675a2000-005c675a3000( 4.000 KiB): 3 Hi, Barry Actually, we also had found the same problem in redis by ourselves tool[1]. The DAMON can not split the large anon VMA well, and the anon VMA has 10G~20G memory. I guess the whole region doesn't have sufficient hot areas to been monitored or found by DAMON, likes one or more address choose by DAMON not been accessed during sample period. I'm not sure whether sets init_regions can deal with the above problem, or dynamic choose one or limited number VMA to monitor. I'm not sure, just share my idea. [1] https://github.com/aliyun/data-profile-tools.git > > Typical characteristics of a large Android app is that it has > thousands of vma and very large virtual address spaces: > ~/damo # pmap 2550 | wc -l > 8522 > > ~/damo # pmap 2550 > ... > 0000007992bbe000 4K r---- [ anon ] > 0000007992bbf000 24K rw--- [ anon ] > 0000007fe8753000 4K ----- [ anon ] > 0000007fe8754000 8188K rw--- [ stack ] > total 36742112K > > Because the whole vma list is too long, I have put the list here for > you to download: > wget http://www.linuxep.com/patches/android-app-vmas > > I can reproduce this problem on other Apps like youtube as well. > I suppose we need to boost the algorithm of splitting regions for this > kind of application. > Any thoughts? > > Thanks > Barry