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=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 2B534C433F5 for ; Mon, 27 Aug 2018 02:02:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E62112174A for ; Mon, 27 Aug 2018 02:02:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E62112174A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.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 S1727298AbeH0Fqf (ORCPT ); Mon, 27 Aug 2018 01:46:35 -0400 Received: from mga03.intel.com ([134.134.136.65]:18333 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726406AbeH0Fqf (ORCPT ); Mon, 27 Aug 2018 01:46:35 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga103.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 26 Aug 2018 19:02:06 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.53,293,1531810800"; d="scan'208";a="75801307" Received: from devel-ww.sh.intel.com ([10.239.48.110]) by FMSMGA003.fm.intel.com with ESMTP; 26 Aug 2018 19:01:31 -0700 From: Wei Wang To: virtio-dev@lists.oasis-open.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, linux-mm@kvack.org, mst@redhat.com, mhocko@kernel.org, akpm@linux-foundation.org, dgilbert@redhat.com Cc: torvalds@linux-foundation.org, pbonzini@redhat.com, wei.w.wang@intel.com, liliang.opensource@gmail.com, yang.zhang.wz@gmail.com, quan.xu0@gmail.com, nilal@redhat.com, riel@redhat.com, peterx@redhat.com, quintela@redhat.com Subject: [PATCH v37 0/3] Virtio-balloon: support free page reporting Date: Mon, 27 Aug 2018 09:32:16 +0800 Message-Id: <1535333539-32420-1-git-send-email-wei.w.wang@intel.com> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The new feature, VIRTIO_BALLOON_F_FREE_PAGE_HINT, implemented by this series enables the virtio-balloon driver to report hints of guest free pages to host. It can be used to accelerate virtual machine (VM) live migration. Here is an introduction of this usage: Live migration needs to transfer the VM's memory from the source machine to the destination round by round. For the 1st round, all the VM's memory is transferred. From the 2nd round, only the pieces of memory that were written by the guest (after the 1st round) are transferred. One method that is popularly used by the hypervisor to track which part of memory is written is to have the hypervisor write-protect all the guest memory. This feature enables the optimization by skipping the transfer of guest free pages during VM live migration. It is not concerned that the memory pages are used after they are given to the hypervisor as a hint of the free pages, because they will be tracked by the hypervisor and transferred in the subsequent round if they are used and written. * Tests 1 Test Environment Host: Intel(R) Xeon(R) CPU E5-2699 v4 @ 2.20GHz Migration setup: migrate_set_speed 100G, migrate_set_downtime 400ms 2 Test Results (results are averaged over several repeated runs) 2.1 Guest setup: 8G RAM, 4 vCPU 2.1.1 Idle guest live migration time Optimization v.s. Legacy = 620ms vs 2970ms --> ~79% reduction 2.1.2 Guest live migration with Linux compilation workload (i.e. make bzImage -j4) running 1) Live Migration Time: Optimization v.s. Legacy = 2273ms v.s. 4502ms --> ~50% reduction 2) Linux Compilation Time: Optimization v.s. Legacy = 8min42s v.s. 8min43s --> no obvious difference 2.2 Guest setup: 128G RAM, 4 vCPU 2.2.1 Idle guest live migration time Optimization v.s. Legacy = 5294ms vs 41651ms --> ~87% reduction 2.2.2 Guest live migration with Linux compilation workload 1) Live Migration Time: Optimization v.s. Legacy = 8816ms v.s. 54201ms --> 84% reduction 2) Linux Compilation Time: Optimization v.s. Legacy = 8min30s v.s. 8min36s --> no obvious difference ChangeLog: v36->v37: - free the reported pages to mm when receives a DONE cmd from host. Please see patch 1's commit log for reasons. Please see patch 1's commit for detailed explanations. For ChangeLogs from v22 to v36, please reference https://lkml.org/lkml/2018/7/20/199 For ChangeLogs before v21, please reference https://lwn.net/Articles/743660/ Wei Wang (3): virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT mm/page_poison: expose page_poisoning_enabled to kernel modules virtio-balloon: VIRTIO_BALLOON_F_PAGE_POISON drivers/virtio/virtio_balloon.c | 374 ++++++++++++++++++++++++++++++++---- include/uapi/linux/virtio_balloon.h | 8 + mm/page_poison.c | 6 + 3 files changed, 355 insertions(+), 33 deletions(-) -- 2.7.4