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=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS 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 3F2C3C43381 for ; Tue, 19 Feb 2019 18:43:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 09D4F21479 for ; Tue, 19 Feb 2019 18:43:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=stwm.de header.i=@stwm.de header.b="BQKXjjZw" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728376AbfBSSnZ (ORCPT ); Tue, 19 Feb 2019 13:43:25 -0500 Received: from mailin.studentenwerk.mhn.de ([141.84.225.229]:53098 "EHLO email.studentenwerk.mhn.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725875AbfBSSnY (ORCPT ); Tue, 19 Feb 2019 13:43:24 -0500 Received: from mailhub.studentenwerk.mhn.de (mailhub.studentenwerk.mhn.de [127.0.0.1]) by email.studentenwerk.mhn.de (Postfix) with ESMTP id 443qPQ6bmNzRhRx; Tue, 19 Feb 2019 19:43:22 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=stwm.de; s=stwm-20170627; t=1550601802; bh=K5MS3jZ13BGgh3RDJZiSh61A7blwovI8lflGwDP8VL8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BQKXjjZwoTTYNQUcaNC+Jl1dGibLplg9PPcbHCS2jM6/HZwYpnPiZ89xe+PMG6hyI kfPcyNmGjNGHnRtZIjRkiKRzpV/TX+AGdt/9/PMC03gsKIugQxLNmjSPUMuZmP1+9U XyEtjPUJgNzZDP5aOLcrWOafrzejEN4SvdRA6rZmuBYyfXv1wgj8BTJy14HY1b7jP7 Z0ZWr4yRrxembIkboC25ex5d7/u8+Q3igU19rB7lUgkgPh51EXFcaXterdMwmlOBrd /0w+E/y66LIoKuF2i2ksYNPvhF/4Tsgrf2IrdL1WK0wC8Z8xotMys96v+nsm5oKWBo BIFPcAJ1Bhm0g== From: Wolfgang Walter To: Sasha Levin Cc: Rik van Riel , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, stable@vger.kernel.org, Dave Chinner , Roman Gushchin , Spock , Michal Hocko , Andrew Morton , Linus Torvalds Subject: Re: [PATCH 4.20 71/92] Revert "mm: slowly shrink slabs with a relatively small number of objects" Date: Tue, 19 Feb 2019 19:43:22 +0100 Message-ID: <4113759.4IQ3NfHFaI@stwm.de> User-Agent: KMail/4.14.3 (Linux/4.18.12-041812-generic; KDE/4.14.13; x86_64; ; ) In-Reply-To: <20190218193452.GV10616@sasha-vm> References: <20190218133454.668268457@linuxfoundation.org> <20190218193452.GV10616@sasha-vm> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="iso-8859-1" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Montag, 18. Februar 2019, 14:34:52 schrieb Sasha Levin: > On Mon, Feb 18, 2019 at 10:30:44AM -0500, Rik van Riel wrote: > >On Mon, 2019-02-18 at 14:43 +0100, Greg Kroah-Hartman wrote: > >> 4.20-stable review patch. If anyone has any objections, please le= t > >> me know. > >>=20 > >> ------------------ > >>=20 > >> From: Dave Chinner > >>=20 > >> commit a9a238e83fbb0df31c3b9b67003f8f9d1d1b6c96 upstream. > >>=20 > >> This reverts commit 172b06c32b9497 ("mm: slowly shrink slabs with = a > >> relatively small number of objects"). > > > >This revert will result in the slab caches of dead > >cgroups with a small number of remaining objects never > >getting reclaimed, which can be a memory leak in some > >configurations. >=20 > What's the "right" choice though? we get either leaky cgroups or hang= ing > xfs. This not only made xfs hang. (Since 4.19.3) on two of our servers ext4 = got so=20 sluggish that login with ssh needed a minute and more. bash tab complet= ion was=20 unusable. Sometimes systemd-journald was restarted with "Watchdog timeo= ut=20 (limit 3min)!", (journal also was on ext4). >=20 > >But hey, that's your tradeoff to make. >=20 > I don't think that any decision was made here, the stable tree simply= > follows upstream with regards to fixes and bugs such as these: we rem= ain > "bug compatible" with upstream in these scenarios, there was no decis= ion > made to prefer either bug. >=20 > -- > Thanks, > Sasha Regards --=20 Wolfgang Walter Studentenwerk M=FCnchen Anstalt des =F6ffentlichen Rechts