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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 72E1AC282CE for ; Wed, 13 Feb 2019 20:01:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4C58D20675 for ; Wed, 13 Feb 2019 20:01:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732727AbfBMUBp (ORCPT ); Wed, 13 Feb 2019 15:01:45 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:57008 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726333AbfBMUBp (ORCPT ); Wed, 13 Feb 2019 15:01:45 -0500 Received: from localhost.localdomain (c-71-198-47-131.hsd1.ca.comcast.net [71.198.47.131]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 29EB51150; Wed, 13 Feb 2019 20:01:44 +0000 (UTC) Date: Wed, 13 Feb 2019 12:01:43 -0800 From: akpm@linux-foundation.org To: dairinin@gmail.com, dchinner@redhat.com, guro@fb.com, linux@stwm.de, mhocko@kernel.org, mm-commits@vger.kernel.org, riel@surriel.com, stable@vger.kernel.org Subject: [merged] =?US-ASCII?Q?revert-mm-slowly-shrink-slabs-with-a-relatively-small-num?= =?US-ASCII?Q?ber-of-objects.patch?= removed from -mm tree Message-ID: <20190213200143.3BISjM2KM%akpm@linux-foundation.org> User-Agent: s-nail v14.8.16 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch titled Subject: Revert "mm: slowly shrink slabs with a relatively small number of objects" has been removed from the -mm tree. Its filename was revert-mm-slowly-shrink-slabs-with-a-relatively-small-number-of-objects.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Dave Chinner Subject: Revert "mm: slowly shrink slabs with a relatively small number of objects" This reverts 172b06c32b9497 ("mm: slowly shrink slabs with a relatively small number of objects"). This change changes the agressiveness of shrinker reclaim, causing small cache and low priority reclaim to greatly increase scanning pressure on small caches. As a result, light memory pressure has a disproportionate affect on small caches, and causes large caches to be reclaimed much faster than previously. As a result, it greatly perturbs the delicate balance of the VFS caches (dentry/inode vs file page cache) such that the inode/dentry caches are reclaimed much, much faster than the page cache and this drives us into several other caching imbalance related problems. As such, this is a bad change and needs to be reverted. [Needs some massaging to retain the later seekless shrinker modifications.] Link: http://lkml.kernel.org/r/20190130041707.27750-3-david@fromorbit.com Fixes: 172b06c32b9497 ("mm: slowly shrink slabs with a relatively small number of objects") Signed-off-by: Dave Chinner Cc: Wolfgang Walter Cc: Roman Gushchin Cc: Spock Cc: Rik van Riel Cc: Michal Hocko Cc: Signed-off-by: Andrew Morton --- mm/vmscan.c | 10 ---------- 1 file changed, 10 deletions(-) --- a/mm/vmscan.c~revert-mm-slowly-shrink-slabs-with-a-relatively-small-number-of-objects +++ a/mm/vmscan.c @@ -491,16 +491,6 @@ static unsigned long do_shrink_slab(stru delta = freeable / 2; } - /* - * Make sure we apply some minimal pressure on default priority - * even on small cgroups. Stale objects are not only consuming memory - * by themselves, but can also hold a reference to a dying cgroup, - * preventing it from being reclaimed. A dying cgroup with all - * corresponding structures like per-cpu stats and kmem caches - * can be really big, so it may lead to a significant waste of memory. - */ - delta = max_t(unsigned long long, delta, min(freeable, batch_size)); - total_scan += delta; if (total_scan < 0) { pr_err("shrink_slab: %pF negative objects to delete nr=%ld\n", _ Patches currently in -mm which might be from dchinner@redhat.com are