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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS 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 27731C5CFE7 for ; Wed, 11 Jul 2018 19:36:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D2846213A2 for ; Wed, 11 Jul 2018 19:36:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D2846213A2 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389483AbeGKTmn (ORCPT ); Wed, 11 Jul 2018 15:42:43 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:56166 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726783AbeGKTmm (ORCPT ); Wed, 11 Jul 2018 15:42:42 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 2DCD940AC6DE; Wed, 11 Jul 2018 19:36:54 +0000 (UTC) Received: from redhat.com (ovpn-112-75.rdu2.redhat.com [10.10.112.75]) by smtp.corp.redhat.com (Postfix) with SMTP id 8FABA2026D6B; Wed, 11 Jul 2018 19:36:50 +0000 (UTC) Date: Wed, 11 Jul 2018 22:36:50 +0300 From: "Michael S. Tsirkin" To: Michal Hocko Cc: Wei Wang , Linus Torvalds , virtio-dev@lists.oasis-open.org, Linux Kernel Mailing List , virtualization , KVM list , linux-mm , Andrew Morton , Paolo Bonzini , liliang.opensource@gmail.com, yang.zhang.wz@gmail.com, quan.xu0@gmail.com, nilal@redhat.com, Rik van Riel , peterx@redhat.com Subject: Re: [PATCH v35 1/5] mm: support to get hints of free page blocks Message-ID: <20180711223040-mutt-send-email-mst@kernel.org> References: <1531215067-35472-1-git-send-email-wei.w.wang@intel.com> <1531215067-35472-2-git-send-email-wei.w.wang@intel.com> <5B455D50.90902@intel.com> <20180711092152.GE20050@dhcp22.suse.cz> <5B45E17D.2090205@intel.com> <20180711110949.GJ20050@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180711110949.GJ20050@dhcp22.suse.cz> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Wed, 11 Jul 2018 19:36:54 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Wed, 11 Jul 2018 19:36:54 +0000 (UTC) for IP:'10.11.54.4' DOMAIN:'int-mx04.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'mst@redhat.com' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 11, 2018 at 01:09:49PM +0200, Michal Hocko wrote: > But let me note that I am not really convinced how this (or previous) > approach will really work in most workloads. We tend to cache heavily so > there is rarely any memory free. It might be that it's worth flushing the cache when VM is migrating. Or maybe we should implement virtio-tmem or add transcendent memory support to the balloon. -- MST