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 X-Spam-Level: X-Spam-Status: No, score=-3.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FSL_HELO_FAKE,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 441C6C4649B for ; Fri, 5 Jul 2019 12:45:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1CEA0218A3 for ; Fri, 5 Jul 2019 12:45:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="Y78t9ohm" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728738AbfGEMpK (ORCPT ); Fri, 5 Jul 2019 08:45:10 -0400 Received: from mail-pl1-f193.google.com ([209.85.214.193]:44806 "EHLO mail-pl1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727652AbfGEMpJ (ORCPT ); Fri, 5 Jul 2019 08:45:09 -0400 Received: by mail-pl1-f193.google.com with SMTP id t14so1490534plr.11 for ; Fri, 05 Jul 2019 05:45:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=dF5ldfW86FJCU5Kc3o1c+7BuYCZNz4gnsUxsM2MILhg=; b=Y78t9ohm9IjqJTYbAV0G0UpCaRpc5X9RScVdIdmz4eqVB1CtoQpRVENQv5H9OJB6u3 IHW38yAnNbwzW6vcGSiPkXs9kW4CnIKtbKQQihf+CPDRaHhL04ZyRYbRyfKQffGvavIp D8IdAu4ImWWGg3ot7QhkuD+LT+WNmRKXlpEXE= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=dF5ldfW86FJCU5Kc3o1c+7BuYCZNz4gnsUxsM2MILhg=; b=I9ujp4KkW1XcW5pTsdi6bMmDsd3BK83LxcLkrT7JK8jSEELJUshWlIpE640q/oa89u aRBfuVtcIbwh1T1bWFpoV7KqN8oftBuX3gAWyLkGTZo1foAEQbQ7b+8poQ7LplGt8DWs 9VvKwPdAhZXPezFugIq07B1u6QbMh9ndiKoT6PbYvQem3KEP1Cp9hKaq3K7Dv7l/n0Pi YKE+AOv83b6MlEvW4AG3yY23ZBpwAtKDxOLnItVx305DaJS1+B188MAWCUOSYEjZ7374 AsjI2pARxMahU7ya3JpOfQpW8XwCG8D+NupnmX496D3M5YsZ66UNTTraHQY4eq0sC8x7 5eVw== X-Gm-Message-State: APjAAAXvIkASRjDEk4SLFEWjirBi1QAOHWn/cK+aMhisI3AZbNylLoKH ZpbnKbjxipRjsh6I+werBBKS X-Google-Smtp-Source: APXvYqxMUTixTbN+cdcvlkTjbvWDrPyHAWnhOqeIT0sxQ7x+/ZOrGTKueCUPUnH3QwRNCyffO+Wgnw== X-Received: by 2002:a17:902:8b88:: with SMTP id ay8mr5266993plb.139.1562330709214; Fri, 05 Jul 2019 05:45:09 -0700 (PDT) Received: from google.com ([2401:fa00:1:b:d89e:cfa6:3c8:e61b]) by smtp.gmail.com with ESMTPSA id y22sm8626527pgj.38.2019.07.05.05.45.07 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Fri, 05 Jul 2019 05:45:08 -0700 (PDT) Date: Fri, 5 Jul 2019 20:45:05 +0800 From: Kuo-Hsin Yang To: Michal Hocko Cc: Andrew Morton , Johannes Weiner , Minchan Kim , Sonny Rao , linux-kernel@vger.kernel.org, linux-mm@kvack.org, stable@vger.kernel.org Subject: Re: [PATCH] mm: vmscan: scan anonymous pages on file refaults Message-ID: <20190705124505.GA173726@google.com> References: <20190628111627.GA107040@google.com> <20190701081038.GA83398@google.com> <20190703143057.GQ978@dhcp22.suse.cz> <20190704094716.GA245276@google.com> <20190704110425.GD5620@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190704110425.GD5620@dhcp22.suse.cz> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 04, 2019 at 01:04:25PM +0200, Michal Hocko wrote: > On Thu 04-07-19 17:47:16, Kuo-Hsin Yang wrote: > > On Wed, Jul 03, 2019 at 04:30:57PM +0200, Michal Hocko wrote: > > > > > > How does the reclaim behave with workloads with file backed data set > > > not fitting into the memory? Aren't we going to to swap a lot - > > > something that the heuristic is protecting from? > > > > > > > In common case, most of the pages in a large file backed data set are > > non-executable. When there are a lot of non-executable file pages, > > usually more file pages are scanned because of the recent_scanned / > > recent_rotated ratio. > > > > I modified the test program to set the accessed sizes of the executable > > and non-executable file pages respectively. The test program runs on 2GB > > RAM VM with kernel 5.2.0-rc7 and this patch, allocates 2000 MB anonymous > > memory, then accesses 100 MB executable file pages and 2100 MB > > non-executable file pages for 10 times. The test also prints the file > > and anonymous page sizes in kB from /proc/meminfo. There are not too > > many swaps in this test case. I got similar test result without this > > patch. > > Could you record swap out stats please? Also what happens if you have > multiple readers? Checked the swap out stats during the test [1], 19006 pages swapped out with this patch, 3418 pages swapped out without this patch. There are more swap out, but I think it's within reasonable range when file backed data set doesn't fit into the memory. $ ./thrash 2000 100 2100 5 1 # ANON_MB FILE_EXEC FILE_NOEXEC ROUNDS PROCESSES Allocate 2000 MB anonymous pages active_anon: 1613644, inactive_anon: 348656, active_file: 892, inactive_file: 1384 (kB) pswpout: 7972443, pgpgin: 478615246 Access 100 MB executable file pages Access 2100 MB regular file pages File access time, round 0: 12.165, (sec) active_anon: 1433788, inactive_anon: 478116, active_file: 17896, inactive_file: 24328 (kB) File access time, round 1: 11.493, (sec) active_anon: 1430576, inactive_anon: 477144, active_file: 25440, inactive_file: 26172 (kB) File access time, round 2: 11.455, (sec) active_anon: 1427436, inactive_anon: 476060, active_file: 21112, inactive_file: 28808 (kB) File access time, round 3: 11.454, (sec) active_anon: 1420444, inactive_anon: 473632, active_file: 23216, inactive_file: 35036 (kB) File access time, round 4: 11.479, (sec) active_anon: 1413964, inactive_anon: 471460, active_file: 31728, inactive_file: 32224 (kB) pswpout: 7991449 (+ 19006), pgpgin: 489924366 (+ 11309120) With 4 processes accessing non-overlapping parts of a large file, 30316 pages swapped out with this patch, 5152 pages swapped out without this patch. The swapout number is small comparing to pgpgin. [1]: https://github.com/vovo/testing/blob/master/mem_thrash.c