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=-2.5 required=3.0 tests=MAILING_LIST_MULTI,SPF_PASS, USER_AGENT_MUTT autolearn=ham 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 BB4CCC67863 for ; Mon, 22 Oct 2018 08:33:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 57ED620779 for ; Mon, 22 Oct 2018 08:33:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 57ED620779 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728067AbeJVQu4 (ORCPT ); Mon, 22 Oct 2018 12:50:56 -0400 Received: from mx2.suse.de ([195.135.220.15]:59646 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727509AbeJVQu4 (ORCPT ); Mon, 22 Oct 2018 12:50:56 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id D09C1AF54; Mon, 22 Oct 2018 08:33:22 +0000 (UTC) Date: Mon, 22 Oct 2018 10:33:22 +0200 From: Michal Hocko To: Spock Cc: linux-kernel@vger.kernel.org, Roman Gushchin , Rik van Riel , Johannes Weiner , Vladimir Davydov , Shakeel Butt , Andrew Morton , Sasha Levin , Greg Kroah-Hartman , linux-mm@kvack.org Subject: Re: Memory management issue in 4.18.15 Message-ID: <20181022083322.GE32333@dhcp22.suse.cz> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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 Cc som more people. I am wondering why 172b06c32b94 ("mm: slowly shrink slabs with a relatively small number of objects") has been backported to the stable tree when not marked that way. Put that aside it seems likely that the upstream kernel will have the same issue I suspect. Roman, could you have a look please? On Sat 20-10-18 14:41:40, 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 -- Michal Hocko SUSE Labs