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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=no 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 0A014CA9EA1 for ; Fri, 18 Oct 2019 10:56:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D80D12246E for ; Fri, 18 Oct 2019 10:56:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2408205AbfJRK4J (ORCPT ); Fri, 18 Oct 2019 06:56:09 -0400 Received: from outbound-smtp29.blacknight.com ([81.17.249.32]:55518 "EHLO outbound-smtp29.blacknight.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2405188AbfJRK4J (ORCPT ); Fri, 18 Oct 2019 06:56:09 -0400 Received: from mail.blacknight.com (unknown [81.17.254.16]) by outbound-smtp29.blacknight.com (Postfix) with ESMTPS id 5DF5DD056D for ; Fri, 18 Oct 2019 11:56:07 +0100 (IST) Received: (qmail 30710 invoked from network); 18 Oct 2019 10:56:07 -0000 Received: from unknown (HELO stampy.112glenside.lan) (mgorman@techsingularity.net@[84.203.19.210]) by 81.17.254.9 with ESMTPA; 18 Oct 2019 10:56:07 -0000 From: Mel Gorman To: Andrew Morton Cc: Michal Hocko , Vlastimil Babka , Thomas Gleixner , Matt Fleming , Borislav Petkov , Linux-MM , Linux Kernel Mailing List , Mel Gorman Subject: [PATCH 0/3] Recalculate per-cpu page allocator batch and high limits after deferred meminit Date: Fri, 18 Oct 2019 11:56:03 +0100 Message-Id: <20191018105606.3249-1-mgorman@techsingularity.net> X-Mailer: git-send-email 2.16.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org A private report stated that system CPU usage was excessive on an AMD EPYC 2 machine while building kernels with much longer build times than expected. The issue is partially explained by high zone lock contention due to the per-cpu page allocator batch and high limits being calculated incorrectly. This series addresses a large chunk of the problem. Patch 1 is mostly cosmetic but prepares for patch 2 which is the real fix. Patch 3 is definiely cosmetic but was noticed while implementing the fix. Proper details are in the changelog for patch 2. include/linux/mm.h | 3 --- mm/internal.h | 3 +++ mm/page_alloc.c | 33 ++++++++++++++++++++------------- 3 files changed, 23 insertions(+), 16 deletions(-) -- 2.16.4