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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 3DC6BC19759 for ; Mon, 5 Aug 2019 00:34:52 +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 149882086D for ; Mon, 5 Aug 2019 00:34:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 149882086D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.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]:49998 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1huQxf-0003Qv-5m for qemu-devel@archiver.kernel.org; Sun, 04 Aug 2019 20:34:51 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:41512) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1huQxC-0002kW-AT for qemu-devel@nongnu.org; Sun, 04 Aug 2019 20:34:23 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1huQxB-0007uV-3g for qemu-devel@nongnu.org; Sun, 04 Aug 2019 20:34:22 -0400 Received: from mga01.intel.com ([192.55.52.88]:6599) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1huQxA-0007u2-Qm for qemu-devel@nongnu.org; Sun, 04 Aug 2019 20:34:21 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 04 Aug 2019 17:34:18 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,347,1559545200"; d="scan'208";a="373537832" Received: from richard.sh.intel.com (HELO localhost) ([10.239.159.54]) by fmsmga006.fm.intel.com with ESMTP; 04 Aug 2019 17:34:18 -0700 Date: Mon, 5 Aug 2019 08:33:50 +0800 From: Wei Yang To: Ivan Ren Message-ID: <20190805003350.GA1311@richard> References: <1564741121-1840-1-git-send-email-ivanren@tencent.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1564741121-1840-1-git-send-email-ivanren@tencent.com> User-Agent: Mutt/1.9.4 (2018-02-28) X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 192.55.52.88 Subject: Re: [Qemu-devel] [PATCH v3] migration: always initial ram_counters for a new migration 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: Wei Yang Cc: qemu-devel@nongnu.org, richardw.yang@linux.intel.com, dgilbert@redhat.com, quintela@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Fri, Aug 02, 2019 at 06:18:41PM +0800, Ivan Ren wrote: >From: Ivan Ren > >This patch fix a multifd migration bug in migration speed calculation, this >problem can be reproduced as follows: >1. start a vm and give a heavy memory write stress to prevent the vm be > successfully migrated to destination >2. begin a migration with multifd >3. migrate for a long time [actually, this can be measured by transferred bytes] >4. migrate cancel >5. begin a new migration with multifd, the migration will directly run into > migration_completion phase > >Reason as follows: > >Migration update bandwidth and s->threshold_size in function >migration_update_counters after BUFFER_DELAY time: > > current_bytes = migration_total_bytes(s); > transferred = current_bytes - s->iteration_initial_bytes; > time_spent = current_time - s->iteration_start_time; > bandwidth = (double)transferred / time_spent; > s->threshold_size = bandwidth * s->parameters.downtime_limit; > >In multifd migration, migration_total_bytes function return >qemu_ftell(s->to_dst_file) + ram_counters.multifd_bytes. >s->iteration_initial_bytes will be initialized to 0 at every new migration, >but ram_counters is a global variable, and history migration data will be >accumulated. So if the ram_counters.multifd_bytes is big enough, it may lead >pending_size >= s->threshold_size become false in migration_iteration_run >after the first migration_update_counters. > >Signed-off-by: Ivan Ren >Reviewed-by: Juan Quintela >Suggested-by: Wei Yang >--- >v2->v3: >- fix the bug of update_iteration_initial_status function prototype > Code looks good. Have you verified on this version? BTW, you didn't address the multifd count in this patch, right? -- Wei Yang Help you, Help me