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=-6.6 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 983AEC433FF for ; Thu, 1 Aug 2019 08:11:20 +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 604F5205F4 for ; Thu, 1 Aug 2019 08:11:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="lzVliYtc" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 604F5205F4 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:46308 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1ht6BD-0004Dv-JC for qemu-devel@archiver.kernel.org; Thu, 01 Aug 2019 04:11:19 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:48928) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1ht6Ah-0003nj-OL for qemu-devel@nongnu.org; Thu, 01 Aug 2019 04:10:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ht6Ag-0006Bq-68 for qemu-devel@nongnu.org; Thu, 01 Aug 2019 04:10:47 -0400 Received: from mail-io1-xd42.google.com ([2607:f8b0:4864:20::d42]:40929) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1ht6Af-0006B3-WA for qemu-devel@nongnu.org; Thu, 01 Aug 2019 04:10:46 -0400 Received: by mail-io1-xd42.google.com with SMTP id h6so17199053iom.7 for ; Thu, 01 Aug 2019 01:10:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=LEbZ3U87Fz4s3zCQUlQJ1Yb3TVozv0tUTPqcwYsHvHM=; b=lzVliYtcYIV5m60q9rLTVFNmEqv7hBHOeE5dwcGfkoWIVqRHH8ie5AiYt+1r81KxA6 rAkf+rY6YoUwWU0SHGRwtZ+B2aRgxFD0/IsGiNWeumZl73QFvovTnPdSe+TPURB8Z+Qz Yeo+WE+Q8P18V2Be6F2SlQy1uLvFhfhuwTphArcmSCWVqSoVgPhntcQpDTq0bbs1R1T3 7ojYqaZyq5WxBYXgZW1ivTXNxbFrzUX6YjHOqbGoovFSb5IuQapki1Lhe1IOVL28Qx31 QDE+we7k7aiqm2H0LvyZeHLvZXYfG6bEdIDh2H3NOtC5hKFK3ki+/cyaUC06gQNfOfd9 dQig== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=LEbZ3U87Fz4s3zCQUlQJ1Yb3TVozv0tUTPqcwYsHvHM=; b=IwdGHdDTtKwKw1ofUcHJWyWmEm7mlK7q6mcVCb93JmzTjrdSKNoiGnBw7NOdkPsxKG wKaTfUA9jAsR3SGopTcR/8VqnH3UQ9A3lv8v5dFzz44evXewvuqUpUnAXLnu3552g+nA hCvuudocn450Pm7+MVD4CHrJvmgZAfFayOjTEhfx+bV2P7K7Xq/dY+DpfL2udKUyH5T5 WxgvNeWXsYu3gDLRLZmOs5yzs3W4pbgkfQ+5rpr+IWrW2dJHYgRmLknKYt4SOaSNg9GZ Qa4vy+nj7n3Bk50JABrcGyN59kPgOt6aAZIsQ9/vQZ7ixKEowP37d+owvIkjkXxKomtL FbpA== X-Gm-Message-State: APjAAAXrHZ8zPuqsid8lC6/nyuuaJEl1rYS/hxm+P1jM1/JqvQNWA/Ol JBznaz1U6L9LIT1fcdxAtpQ4I/BGlfkqAZzZji5mTJEx X-Google-Smtp-Source: APXvYqwAM+2PO+Uj/MJMLWfYstjIIMeortBs/sHURbSosuPOqYVCpX6F9fuVYvaNFkcAg0H//lNpAdR20VmsPSQyrMo= X-Received: by 2002:a02:a1c7:: with SMTP id o7mr135123544jah.26.1564647045103; Thu, 01 Aug 2019 01:10:45 -0700 (PDT) MIME-Version: 1.0 References: <1564464992-22305-1-git-send-email-ivanren@tencent.com> <20190801022118.GA21992@richard> In-Reply-To: <20190801022118.GA21992@richard> From: Ivan Ren Date: Thu, 1 Aug 2019 16:10:34 +0800 Message-ID: To: Wei Yang X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2607:f8b0:4864:20::d42 Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.23 Subject: Re: [Qemu-devel] [PATCH] 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: , Cc: qemu-devel@nongnu.org, dgilbert@redhat.com, quintela@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" >> s->iteration_start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); >>+ /* >>+ * Update s->iteration_initial_bytes to match s->iteration_start_time. >>+ */ >>+ s->iteration_initial_bytes = migration_total_bytes(s); > >Is this one necessary? We have sent out nothing yet. Yes, currently nothing has been sent yet at this point. Is that better to always match the update of iteration_initial_bytes and iteration_start_time in a explicit way to avoid some potential missing? Thanks. On Thu, Aug 1, 2019 at 10:21 AM Wei Yang wrote: > On Tue, Jul 30, 2019 at 01:36:32PM +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 > >--- > > migration/migration.c | 15 ++++++++++++++- > > migration/savevm.c | 1 + > > 2 files changed, 15 insertions(+), 1 deletion(-) > > > >diff --git a/migration/migration.c b/migration/migration.c > >index 8a607fe1e2..d35a6ae6f9 100644 > >--- a/migration/migration.c > >+++ b/migration/migration.c > >@@ -1908,6 +1908,11 @@ static bool migrate_prepare(MigrationState *s, > bool blk, bool blk_inc, > > } > > > > migrate_init(s); > >+ /* > >+ * set ram_counters memory to zero for a > >+ * new migration > >+ */ > >+ memset(&ram_counters, 0, sizeof(ram_counters)); > > > > return true; > > } > >@@ -3187,6 +3192,10 @@ static void *migration_thread(void *opaque) > > > > object_ref(OBJECT(s)); > > s->iteration_start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); > >+ /* > >+ * Update s->iteration_initial_bytes to match > s->iteration_start_time. > >+ */ > >+ s->iteration_initial_bytes = migration_total_bytes(s); > > Is this one necessary? We have sent out nothing yet. > > > > > qemu_savevm_state_header(s->to_dst_file); > > > >@@ -3252,7 +3261,11 @@ static void *migration_thread(void *opaque) > > * breaking transferred_bytes and bandwidth calculation > > */ > > s->iteration_start_time = > qemu_clock_get_ms(QEMU_CLOCK_REALTIME); > >- s->iteration_initial_bytes = 0; > >+ /* > >+ * Update s->iteration_initial_bytes to current size to > >+ * avoid historical data lead wrong bandwidth. > >+ */ > >+ s->iteration_initial_bytes = migration_total_bytes(s); > > } > > > > current_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); > >diff --git a/migration/savevm.c b/migration/savevm.c > >index 79ed44d475..480c511b19 100644 > >--- a/migration/savevm.c > >+++ b/migration/savevm.c > >@@ -1424,6 +1424,7 @@ static int qemu_savevm_state(QEMUFile *f, Error > **errp) > > } > > > > migrate_init(ms); > >+ memset(&ram_counters, 0, sizeof(ram_counters)); > > ms->to_dst_file = f; > > > > qemu_mutex_unlock_iothread(); > >-- > >2.17.2 (Apple Git-113) > > > > -- > Wei Yang > Help you, Help me >