From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io1-f70.google.com (mail-io1-f70.google.com [209.85.166.70]) by kanga.kvack.org (Postfix) with ESMTP id 2BE0A6B0003 for ; Sat, 20 Oct 2018 11:37:48 -0400 (EDT) Received: by mail-io1-f70.google.com with SMTP id x5-v6so33604356ioa.6 for ; Sat, 20 Oct 2018 08:37:48 -0700 (PDT) Received: from merlin.infradead.org (merlin.infradead.org. [2001:8b0:10b:1231::1]) by mx.google.com with ESMTPS id b1-v6si17082711jae.32.2018.10.20.08.37.46 for (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Sat, 20 Oct 2018 08:37:46 -0700 (PDT) Subject: Re: Memory management issue in 4.18.15 References: From: Randy Dunlap Message-ID: Date: Sat, 20 Oct 2018 08:37:28 -0700 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Spock , linux-kernel@vger.kernel.org, Linux MM Cc: Andrew Morton , Roman Gushchin , Rik van Riel , Sasha Levin [add linux-mm mailing list + people] On 10/20/18 4:41 AM, Spock wrote: > Hello, > > I have a workload, which creates lots of cache pages. Before 4.18.15, > the behavior was very stable: pagecache is constantly growing until it > consumes all the free memory, and then kswapd is balancing it around > low watermark. After 4.18.15, once in a while khugepaged is waking up > and reclaims almost all the pages from pagecache, so there is always > around 2G of 8G unused. THP is enabled only for madvise case and are > not used. > > The exact change that leads to current behavior is > https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=linux-4.18.y&id=62aad93f09c1952ede86405894df1b22012fd5ab > -- ~Randy