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=-7.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 1979BC33CB1 for ; Tue, 14 Jan 2020 14:57:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DB9262467D for ; Tue, 14 Jan 2020 14:57:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="AI49oSZ5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729080AbgANO5X (ORCPT ); Tue, 14 Jan 2020 09:57:23 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:27356 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727092AbgANO5X (ORCPT ); Tue, 14 Jan 2020 09:57:23 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1579013840; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=bRnkICnNJBIzJOH97eFHI4gLkkkXhQ+8DcPEdenNZ4Q=; b=AI49oSZ5j/ILSJdXRBl6BlPC9gMf6FZte3/qmDo6+qi4KMcnaam8OYiuyJnhf0pPbvyOKV H93iXuAnqOEqMY4LnTmJdBRi+K2L2C9cetFNSWLWk5dLzSe3wvGwJ0BHhyWrPtdGsVmSke offpBobCMcT62owWzR1xwfbQLwM7y8w= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-293-G_2eAZEZOOOvrcdG1DZZ9A-1; Tue, 14 Jan 2020 09:57:17 -0500 X-MC-Unique: G_2eAZEZOOOvrcdG1DZZ9A-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 117DA801E78; Tue, 14 Jan 2020 14:57:15 +0000 (UTC) Received: from llong.remote.csb (ovpn-124-77.rdu2.redhat.com [10.10.124.77]) by smtp.corp.redhat.com (Postfix) with ESMTP id A4ED75DA7D; Tue, 14 Jan 2020 14:57:13 +0000 (UTC) Subject: Re: [mm/hugetlb] c77c0a8ac4: will-it-scale.per_process_ops 15.9% improvement To: Michal Hocko , kernel test robot Cc: Linus Torvalds , Mike Kravetz , Davidlohr Bueso , Kirill Tkhai , "Aneesh Kumar K.V" , Matthew Wilcox , Andi Kleen , Andrew Morton , LKML , lkp@lists.01.org References: <20200114085637.GA29297@shao2-debian> <20200114091251.GE19428@dhcp22.suse.cz> From: Waiman Long Organization: Red Hat Message-ID: Date: Tue, 14 Jan 2020 09:57:14 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: <20200114091251.GE19428@dhcp22.suse.cz> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 1/14/20 4:12 AM, Michal Hocko wrote: > On Tue 14-01-20 16:56:37, kernel test robot wrote: >> Greeting, >> >> FYI, we noticed a 15.9% improvement of will-it-scale.per_process_ops due to commit: >> >> >> commit: c77c0a8ac4c522638a8242fcb9de9496e3cdbb2d ("mm/hugetlb: defer freeing of huge pages if in non-task context") >> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master > This is more than surprising because the patch has only changed the > behavior for hugetlb pages freed from the (soft)interrupt context and > that should be a very rare event. Does the test really generate a lot of > those? > Yes, I have the same question. I was not expecting to see any performance impact. Cheers, Longman