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,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 1F75AC433E0 for ; Fri, 29 May 2020 04:26:23 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E80592074D for ; Fri, 29 May 2020 04:26:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E80592074D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:55770 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jeWb7-0000EN-VV for qemu-devel@archiver.kernel.org; Fri, 29 May 2020 00:26:21 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:59082) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jeWaB-00083J-Ow for qemu-devel@nongnu.org; Fri, 29 May 2020 00:25:23 -0400 Received: from mga02.intel.com ([134.134.136.20]:1921) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jeWaA-0005LT-EX for qemu-devel@nongnu.org; Fri, 29 May 2020 00:25:23 -0400 IronPort-SDR: pw7XQC2K6hECI5ys1Wu6BRnNXlDcnO9snl6Yzn0Vojzm5e1oq9cEQlX8giUNhupuaX0FtnTng1 mp8M7/hjQ0Aw== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 May 2020 21:25:16 -0700 IronPort-SDR: LbimR6ujBCgASJuPZXnR+I9UPBzufB/aMJUq2aUy/HaeKwBGRfuKRCo7pz21sinVhhdMj1UGnA IJvBOc/sk6OA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,447,1583222400"; d="scan'208";a="414847654" Received: from joy-optiplex-7040.sh.intel.com (HELO joy-OptiPlex-7040) ([10.239.13.16]) by orsmga004.jf.intel.com with ESMTP; 28 May 2020 21:25:11 -0700 Date: Fri, 29 May 2020 00:15:17 -0400 From: Yan Zhao To: Alex Williamson Subject: Re: [PATCH Kernel v22 0/8] Add UAPIs to support migration for VFIO devices Message-ID: <20200529041516.GE1378@joy-OptiPlex-7040> References: <1589781397-28368-1-git-send-email-kwankhede@nvidia.com> <20200519105804.02f3cae8@x1.home> <20200525065925.GA698@joy-OptiPlex-7040> <426a5314-6d67-7cbe-bad0-e32f11d304ea@nvidia.com> <20200526141939.2632f100@x1.home> <20200527062358.GD19560@joy-OptiPlex-7040> <20200527084822.GC3001@work-vm> <20200528165906.7d03f689@x1.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200528165906.7d03f689@x1.home> User-Agent: Mutt/1.9.4 (2018-02-28) Received-SPF: pass client-ip=134.134.136.20; envelope-from=yan.y.zhao@intel.com; helo=mga02.intel.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/05/29 00:25:16 X-ACL-Warn: Detected OS = FreeBSD 9.x or newer [fuzzy] X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Yan Zhao Cc: Zhengxiao.zx@alibaba-inc.com, kevin.tian@intel.com, yi.l.liu@intel.com, cjia@nvidia.com, kvm@vger.kernel.org, eskultet@redhat.com, ziye.yang@intel.com, qemu-devel@nongnu.org, cohuck@redhat.com, shuangtai.tst@alibaba-inc.com, "Dr. David Alan Gilbert" , zhi.a.wang@intel.com, mlevitsk@redhat.com, pasic@linux.ibm.com, aik@ozlabs.ru, Kirti Wankhede , eauger@redhat.com, felipe@nutanix.com, jonathan.davies@nutanix.com, changpeng.liu@intel.com, Ken.Xue@amd.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Thu, May 28, 2020 at 04:59:06PM -0600, Alex Williamson wrote: > On Wed, 27 May 2020 09:48:22 +0100 > "Dr. David Alan Gilbert" wrote: > > * Yan Zhao (yan.y.zhao@intel.com) wrote: > > > BTW, for viommu, the downtime data is as below. under the same network > > > condition and guest memory size, and no running dirty data/memory produced > > > by device. > > > (1) viommu off > > > single-round dirty query: downtime ~100ms > > > > Fine. > > > > > (2) viommu on > > > single-round dirty query: downtime 58s > > > > Youch. > > Double Youch! But we believe this is because we're getting the dirty > bitmap one IOMMU leaf page at a time, right? We've enable the kernel > to get a dirty bitmap across multiple mappings, but QEMU isn't yet > taking advantage of it. Do I have this correct? Thanks, > Yes, I think so, but I haven't looked into it yet. Thanks Yan