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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 D3300C4360C for ; Fri, 4 Oct 2019 23:49:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9C1D9215EA for ; Fri, 4 Oct 2019 23:49:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731606AbfJDXtG (ORCPT ); Fri, 4 Oct 2019 19:49:06 -0400 Received: from mga18.intel.com ([134.134.136.126]:42487 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726669AbfJDXtF (ORCPT ); Fri, 4 Oct 2019 19:49:05 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga106.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 04 Oct 2019 16:49:04 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.67,258,1566889200"; d="scan'208";a="205963748" Received: from richard.sh.intel.com (HELO localhost) ([10.239.159.54]) by fmsmga001.fm.intel.com with ESMTP; 04 Oct 2019 16:49:03 -0700 Date: Sat, 5 Oct 2019 07:48:45 +0800 From: Wei Yang To: Matthew Wilcox Cc: Wei Yang , akpm@linux-foundation.org, kirill.shutemov@linux.intel.com, jglisse@redhat.com, mike.kravetz@oracle.com, riel@surriel.com, khlebnikov@yandex-team.ru, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/rmap.c: reuse mergeable anon_vma as parent when fork Message-ID: <20191004234845.GB15415@richard> Reply-To: Wei Yang References: <20191004160632.30251-1-richardw.yang@linux.intel.com> <20191004161120.GI32665@bombadil.infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191004161120.GI32665@bombadil.infradead.org> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 04, 2019 at 09:11:20AM -0700, Matthew Wilcox wrote: >On Sat, Oct 05, 2019 at 12:06:32AM +0800, Wei Yang wrote: >> After this change, kernel build test reduces 20% anon_vma allocation. > >But does it have any effect on elapsed time or peak memory consumption? Do the same kernel build test and record time: Origin real 2m50.467s user 17m52.002s sys 1m51.953s real 2m48.662s user 17m55.464s sys 1m50.553s real 2m51.143s user 17m59.687s sys 1m53.600s Patched real 2m43.733s user 17m25.705s sys 1m41.791s real 2m47.146s user 17m47.451s sys 1m43.474s real 2m45.763s user 17m38.230s sys 1m42.102s For time in sys, it reduced 8.5%. -- Wei Yang Help you, Help me