From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pl1-f200.google.com (mail-pl1-f200.google.com [209.85.214.200]) by kanga.kvack.org (Postfix) with ESMTP id 09E8A6B026A for ; Wed, 31 Oct 2018 09:52:45 -0400 (EDT) Received: by mail-pl1-f200.google.com with SMTP id 3-v6so5107860plc.18 for ; Wed, 31 Oct 2018 06:52:45 -0700 (PDT) Received: from mail.kernel.org (mail.kernel.org. [198.145.29.99]) by mx.google.com with ESMTPS id i13-v6si27207732pgd.311.2018.10.31.06.52.43 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 31 Oct 2018 06:52:43 -0700 (PDT) Date: Wed, 31 Oct 2018 09:52:42 -0400 From: Sasha Levin Subject: Re: [PATCH 4.18] Revert "mm: slowly shrink slabs with a relatively small number of objects" Message-ID: <20181031135242.GI194472@sasha-vm> References: <20181026111859.23807-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20181026111859.23807-1-sashal@kernel.org> Sender: owner-linux-mm@kvack.org List-ID: To: gregkh@linuxfoundation.org Cc: stable@vger.kernel.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, linux-mm@kvack.org On Fri, Oct 26, 2018 at 07:18:59AM -0400, Sasha Levin wrote: >This reverts commit 62aad93f09c1952ede86405894df1b22012fd5ab. > >Which was upstream commit 172b06c32b94 ("mm: slowly shrink slabs with a >relatively small number of objects"). > >The upstream commit was found to cause regressions. While there is a >proposed fix upstream, revent this patch from stable trees for now as >testing the fix will take some time. > >Signed-off-by: Sasha Levin >--- > mm/vmscan.c | 11 ----------- > 1 file changed, 11 deletions(-) > >diff --git a/mm/vmscan.c b/mm/vmscan.c >index fc0436407471..03822f86f288 100644 >--- a/mm/vmscan.c >+++ b/mm/vmscan.c >@@ -386,17 +386,6 @@ static unsigned long do_shrink_slab(struct shrink_control *shrinkctl, > delta = freeable >> priority; > delta *= 4; > do_div(delta, shrinker->seeks); >- >- /* >- * 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", I've queued it up for 4.18. -- Thanks, Sasha