From nobody Wed May 8 14:14:58 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=gmail.com ARC-Seal: i=1; a=rsa-sha256; t=1564465037; cv=none; d=zoho.com; s=zohoarc; b=Nb87bqSKR4FHxSS2orSv3J+KhRywsh54kR7ico999SpjYRim58WsadRKQWckV8IL6jwoLc0H1y+r9JDZUJ0meWUGC4bt2mGntNKfcpu6e0YXOGj3Ryx+nUN9M1PDDd3SBe/Mmj4cT8qvohE8SmgRQWWegKz1zEOHbNe1y+KNzME= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1564465037; h=Cc:Date:From:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:Message-ID:Sender:Subject:To:ARC-Authentication-Results; bh=O+EIdoIntj3n5hnxy+xKUQkRRVsC3Mw51/au0nSQ6tk=; b=lp3mZkPK4unf/OxPss6c5U9hjLpfAdLdaqWIMrNhRVjBYdgs4KbhORQqCcj4ZtjlGqH1NZmYm3U0QYcxRjnu1BelpgcT1aXlRMNz0Jj9dZOie+1NomXoiDuRyLADYyzTUP7FQUjtMDZbIWX5jBK2y9z4+2FJ6ueBacOhuY6KYG8= ARC-Authentication-Results: i=1; mx.zoho.com; dkim=fail; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1564465037194893.5115768915897; Mon, 29 Jul 2019 22:37:17 -0700 (PDT) Received: from localhost ([::1]:58054 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hsKp2-0000iq-9t for importer@patchew.org; Tue, 30 Jul 2019 01:37:16 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:48339) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hsKoa-0000Jx-2r for qemu-devel@nongnu.org; Tue, 30 Jul 2019 01:36:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hsKoY-0007Ck-V6 for qemu-devel@nongnu.org; Tue, 30 Jul 2019 01:36:48 -0400 Received: from mail-pl1-x641.google.com ([2607:f8b0:4864:20::641]:34059) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1hsKoY-0007CT-P0 for qemu-devel@nongnu.org; Tue, 30 Jul 2019 01:36:46 -0400 Received: by mail-pl1-x641.google.com with SMTP id i2so28443658plt.1 for ; Mon, 29 Jul 2019 22:36:46 -0700 (PDT) Received: from VM_85_204_centos.localdomain ([129.226.55.250]) by smtp.gmail.com with ESMTPSA id o14sm52075285pjp.19.2019.07.29.22.36.44 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 29 Jul 2019 22:36:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=O+EIdoIntj3n5hnxy+xKUQkRRVsC3Mw51/au0nSQ6tk=; b=HNb353sLKIfbIXBTctYFSSNHUcWymHGZ5IqZB//PRQgaBLkDRBULOJ6O9amSwR0MWs IbEadsTCHsUceDlXbLX2L5yHrUgvnmGJmJkprzjOyUpqHT6C1OGALqUtv4l0b1i4AlJq nPaThRTkkJ8Ma2zEcaAuauRnD7kKUZipx+7CW/i+aqRmeiIB3eLNcsWEKlefeRlXGMwF 2dcznoLbQrEYj6wKLMVrKYyN+nJpRMLBHfxgIfzAijunCo8Vlqx0nx81S6GBEB0MXFoW DwIQ924SzXuH9wsLffct99vWdTk6PcH4VjEALz359WMnzm5JOOYGq4s7QpoSlJ31nCIS AVdA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=O+EIdoIntj3n5hnxy+xKUQkRRVsC3Mw51/au0nSQ6tk=; b=ubzcNKEV1d3d1HWo4jMJYzGnPMwMqhaBchKPkI33VVqEyB14PxbZF4RofI0Em4016B /ryZ19XIh5FetiGLtSanKdAvFI4MCwljdMQtXc0Tz4fRNtepg+LQEiSJOD35cbvQd7HT QVW0daaxe46b00uHHNmKRCmyG0/Y/ocur/Ta/WORetokrFLMbOn6obskth+lPkFbkuwR XO7sQmvZcaAsArGdIPcf9YvZyQIQo6b00Ti/pdTbA1zT776U3g7Vr6kWXf8vO2wqdNiU 9MUuhH7+0NQy9qAdpHn5mESDkYhlJOyBjlx9kc9SFuMO93sob4ArHYEs0m0RwE/I0zzy joaw== X-Gm-Message-State: APjAAAXlvkk2fO3PY9YRfJyadrCp4/kUj3dPRqiv4rWspdD9/GgyCDwn ygqGe2pBiAz10ATehYmgKP4= X-Google-Smtp-Source: APXvYqyBhsWKxo8CQevm16ikf/eFsLRWWVvqTUftWtWZ26pjFysqOnoNxPZ18RTQDCg00QuMcBS/QA== X-Received: by 2002:a17:902:2b8a:: with SMTP id l10mr113325725plb.283.1564465005729; Mon, 29 Jul 2019 22:36:45 -0700 (PDT) From: Ivan Ren X-Google-Original-From: Ivan Ren To: quintela@redhat.com, dgilbert@redhat.com Date: Tue, 30 Jul 2019 13:36:32 +0800 Message-Id: <1564464992-22305-1-git-send-email-ivanren@tencent.com> X-Mailer: git-send-email 1.8.3.1 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2607:f8b0:4864:20::641 Subject: [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 Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" 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 b= ytes] 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 =3D migration_total_bytes(s); transferred =3D current_bytes - s->iteration_initial_bytes; time_spent =3D current_time - s->iteration_start_time; bandwidth =3D (double)transferred / time_spent; s->threshold_size =3D 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 >=3D s->threshold_size become false in migration_iteration_run after the first migration_update_counters. Signed-off-by: Ivan Ren Reviewed-by: Juan Quintela --- 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, } =20 migrate_init(s); + /* + * set ram_counters memory to zero for a + * new migration + */ + memset(&ram_counters, 0, sizeof(ram_counters)); =20 return true; } @@ -3187,6 +3192,10 @@ static void *migration_thread(void *opaque) =20 object_ref(OBJECT(s)); s->iteration_start_time =3D qemu_clock_get_ms(QEMU_CLOCK_REALTIME); + /* + * Update s->iteration_initial_bytes to match s->iteration_start_time. + */ + s->iteration_initial_bytes =3D migration_total_bytes(s); =20 qemu_savevm_state_header(s->to_dst_file); =20 @@ -3252,7 +3261,11 @@ static void *migration_thread(void *opaque) * breaking transferred_bytes and bandwidth calculation */ s->iteration_start_time =3D qemu_clock_get_ms(QEMU_CLOCK_REALT= IME); - s->iteration_initial_bytes =3D 0; + /* + * Update s->iteration_initial_bytes to current size to + * avoid historical data lead wrong bandwidth. + */ + s->iteration_initial_bytes =3D migration_total_bytes(s); } =20 current_time =3D 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 **err= p) } =20 migrate_init(ms); + memset(&ram_counters, 0, sizeof(ram_counters)); ms->to_dst_file =3D f; =20 qemu_mutex_unlock_iothread(); --=20 2.17.2 (Apple Git-113)