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=-3.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS 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 8C476C10DCE for ; Thu, 12 Mar 2020 14:47:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5F98520724 for ; Thu, 12 Mar 2020 14:47:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=cmpxchg-org.20150623.gappssmtp.com header.i=@cmpxchg-org.20150623.gappssmtp.com header.b="nNate0u0" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727722AbgCLOrx (ORCPT ); Thu, 12 Mar 2020 10:47:53 -0400 Received: from mail-qt1-f196.google.com ([209.85.160.196]:39635 "EHLO mail-qt1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727463AbgCLOrx (ORCPT ); Thu, 12 Mar 2020 10:47:53 -0400 Received: by mail-qt1-f196.google.com with SMTP id f17so3239737qtq.6 for ; Thu, 12 Mar 2020 07:47:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cmpxchg-org.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=bkEMbn273mdTI0AXhfsCYlRybd34rXTvQOuBweyXdAI=; b=nNate0u0S3aVT6rUhoHi/gCeLVVgF1Ym72tleDd+1mq2bhxXMk+lsBEU6d/v8IGA+b zsy0SRB0aYjUpDfxZ7fLcV6y+UvgmFZ0v/5vPLQbYmx78/I3InPTXPh5fOen3gfwj4jV o+0PXJ/uH5PwNAlAsiIbI470nbSRicBtc04BPl44plQcSedwSSztXOutjQ9XS5uyHqdi jsufNn8/4b1dAAvEjn6V0uUAWlUz2+CFYeGAPnzOQ0JS3QrXajrbh73O4xGyEUVIsWwg yU/A1563fUjzs8Nc5f6hPayD9gnnr3nu5GISVBR8NoGuRIJCJV5wkxc/38aZzEbiwEDn KWXA== 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; bh=bkEMbn273mdTI0AXhfsCYlRybd34rXTvQOuBweyXdAI=; b=spZlEJU7n7Lf6+nWf9BYXpycbcWmPCtIyXSvmPN/6sG4asmmBDBCuVAyYPdUAKyTPC qKNT9/qIjPxk08oESYAMCAgBW9dpuWzzpjoCu6bjsHLdjxnSlTuF2MZEoh4sCbwMsDEz s3gLF3uyPPZuyKmA9TAIrjpnF4Ui0L9l1cGbPNBJ4fmy/rInNcahYPNEULrO0UHxEvhN WQ+dJ3OQjJhbWS2Hj5kdgoVkMT8C7tSKNvpKLYJRzBvT7stwpquoImYNQnIVon4t8vDB CxLqCMI7EybqCSPvFUxDtATiwMmPiXgQfYWrzjeqhX/rWYXcQJS0flBcn4ywsfhoV+ru qLrQ== X-Gm-Message-State: ANhLgQ2LHYKjo8341lCXn1iy4YId/BUuOGFDWUrcSn3Fpr8U4GVghbYp 4f4BOD1IMHcfEFvIQDBphYjnzw== X-Google-Smtp-Source: ADFU+vtez/OYPIOGbQ3kCqqnHLmKDJ5OQvSq2g62kT+6Tr+O2gVjdB1Bhf9T9GX+6Ir1rjbjtE8Ndg== X-Received: by 2002:ac8:e45:: with SMTP id j5mr7465910qti.215.1584024471583; Thu, 12 Mar 2020 07:47:51 -0700 (PDT) Received: from localhost ([2620:10d:c091:480::ef6a]) by smtp.gmail.com with ESMTPSA id f13sm13651077qte.53.2020.03.12.07.47.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 12 Mar 2020 07:47:50 -0700 (PDT) Date: Thu, 12 Mar 2020 10:47:49 -0400 From: Johannes Weiner To: js1304@gmail.com Cc: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Michal Hocko , Hugh Dickins , Minchan Kim , Vlastimil Babka , Mel Gorman , kernel-team@lge.com, Joonsoo Kim Subject: Re: [PATCH v2 1/9] mm/vmscan: make active/inactive ratio as 1:1 for anon lru Message-ID: <20200312144749.GG29835@cmpxchg.org> References: <1582175513-22601-1-git-send-email-iamjoonsoo.kim@lge.com> <1582175513-22601-2-git-send-email-iamjoonsoo.kim@lge.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1582175513-22601-2-git-send-email-iamjoonsoo.kim@lge.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 20, 2020 at 02:11:45PM +0900, js1304@gmail.com wrote: > From: Joonsoo Kim > > Current implementation of LRU management for anonymous page has some > problems. Most important one is that it doesn't protect the workingset, > that is, pages on the active LRU list. Although, this problem will be > fixed in the following patchset, the preparation is required and > this patch does it. > > What following patchset does is to restore workingset protection. In this > case, newly created or swap-in pages are started their lifetime on the > inactive list. If inactive list is too small, there is not enough chance > to be referenced and the page cannot become the workingset. > > In order to provide enough chance to the newly anonymous pages, this patch > makes active/inactive LRU ratio as 1:1. Patch 8/9 is a revert of this patch. I assume you did this for the series to be bisectable and partially revertable, but I'm not sure keeping only the first and second patch would be safe: they reduce workingset protection quite dramatically on their own (on a 10G system from 90% of RAM to 50% e.g.) and likely cause regressions. So while patch 2 is probably a lot better with patch 1 than without, it seems a bit unnecessary since we cannot keep patch 2 on its own. We need the rest of the series to make these changes. On the other hand, the patch is small and obviously correct. So no strong feelings either way. > Signed-off-by: Joonsoo Kim Reviewed-by: Johannes Weiner