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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,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 04AC2CA9EC4 for ; Tue, 29 Oct 2019 13:26:48 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id B7B7C21479 for ; Tue, 29 Oct 2019 13:26:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="c1KSpUVm" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B7B7C21479 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 0A1C56B0005; Tue, 29 Oct 2019 09:26:47 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 052A36B0006; Tue, 29 Oct 2019 09:26:46 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EAAE66B0007; Tue, 29 Oct 2019 09:26:46 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0048.hostedemail.com [216.40.44.48]) by kanga.kvack.org (Postfix) with ESMTP id C8B096B0005 for ; Tue, 29 Oct 2019 09:26:46 -0400 (EDT) Received: from smtpin02.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with SMTP id 70EA44DBC for ; Tue, 29 Oct 2019 13:26:46 +0000 (UTC) X-FDA: 76096897212.02.stop32_5832900e3cf03 X-HE-Tag: stop32_5832900e3cf03 X-Filterd-Recvd-Size: 4234 Received: from us-smtp-delivery-1.mimecast.com (us-smtp-1.mimecast.com [207.211.31.81]) by imf40.hostedemail.com (Postfix) with ESMTP for ; Tue, 29 Oct 2019 13:26:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1572355605; 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=4ZnfhT7+7jRkPyL+7J38NPLykuSAFsrZtZChreOrEfg=; b=c1KSpUVmhiQfnmyPNUZAM0NihCm+EfpVFXcsKbOXQpEJOwMMSW4Fx1Vk9QZfht001MiV6+ QqQqWkqa/t4KXJZB+kPd/nN390ala9UeRZN5hAYl9ASf77XfmBCuSQ3Y2rqeH6qrRwhKZi IxuL9/9r/mjjOnUm42OzeaIJ/is8Uy8= 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-133-pCW1U5pPO5aWK09p80hpHQ-1; Tue, 29 Oct 2019 09:26:42 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 5B38B476; Tue, 29 Oct 2019 13:26:40 +0000 (UTC) Received: from [10.36.118.30] (unknown [10.36.118.30]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9A6C9600C4; Tue, 29 Oct 2019 13:26:37 +0000 (UTC) Subject: Re: [RFC v2] mm: add page preemption To: Hillf Danton , Michal Hocko Cc: linux-mm , Andrew Morton , linux-kernel , Matthew Wilcox , Johannes Weiner , Shakeel Butt , Minchan Kim , Mel Gorman , Vladimir Davydov , Jan Kara References: <20191029123058.19060-1-hdanton@sina.com> From: David Hildenbrand Organization: Red Hat GmbH Message-ID: <2586aa78-9120-cd33-7f02-2542b74a64a4@redhat.com> Date: Tue, 29 Oct 2019 14:26:36 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.1.1 MIME-Version: 1.0 In-Reply-To: <20191029123058.19060-1-hdanton@sina.com> Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-MC-Unique: pCW1U5pPO5aWK09p80hpHQ-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 29.10.19 13:30, Hillf Danton wrote: >=20 > Date: Tue, 29 Oct 2019 09:41:53 +0100 Michal Hocko wrote: >> >> As already raised in the review of v1. There is no real life usecase >> described in the changelog. >=20 > No feature, no user; no user, no workloads. > No linux-6.x released, no 6.x users. > Are you going to be one of the users of linux-6.0? >=20 > Even though, I see a use case over there at > https://lore.kernel.org/lkml/20191023120452.GN754@dhcp22.suse.cz/ >=20 > That thread terminated because of preemption, showing us how useful > preemption might be in real life. >=20 >> I have also expressed concerns about how >> such a reclaim would work in the first place >=20 > Based on what? >=20 >> (priority inversion, >=20 > No prio inversion will happen after introducing prio to global reclaim. >=20 >> expensive reclaim etc.). >=20 > No cost, no earn. >=20 >=20 Side note: You should really have a look what your mail client is=20 messing up here. E.g., the reply from Michal correctly had Message-ID: <20191029084153.GD31513@dhcp22.suse.cz> References: <20191026112808.14268-1-hdanton@sina.com> In-Reply-To: <20191026112808.14268-1-hdanton@sina.com> Once you reply to that, you have Message-Id: <20191029123058.19060-1-hdanton@sina.com> In-Reply-To: <20191026112808.14268-1-hdanton@sina.com> References: Instead of Message-Id: <20191029123058.19060-1-hdanton@sina.com> In-Reply-To: <20191029084153.GD31513@dhcp22.suse.cz> References: <20191029084153.GD31513@dhcp22.suse.cz> Which flattens the whole thread hierarchy. Nasty. Please fix that. --=20 Thanks, David / dhildenb