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=-8.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MSGID_FROM_MTA_HEADER,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 DB09DC433DF for ; Wed, 10 Jun 2020 19:06:52 +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 98DED206F7 for ; Wed, 10 Jun 2020 19:06:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=virtuozzo.com header.i=@virtuozzo.com header.b="TWkpzh2C" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 98DED206F7 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=openvz.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:35892 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jj63n-0003bl-TE for qemu-devel@archiver.kernel.org; Wed, 10 Jun 2020 15:06:51 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:56388) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jj5yz-00071d-6w; Wed, 10 Jun 2020 15:01:53 -0400 Received: from mail-db8eur05on2119.outbound.protection.outlook.com ([40.107.20.119]:22675 helo=EUR05-DB8-obe.outbound.protection.outlook.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jj5yx-0005a3-SY; Wed, 10 Jun 2020 15:01:52 -0400 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=O7/CqYnk/DrvHCNReqqamKdi+4L84JOs8XJKN7hIPlAAEmJ4q+D07O1bkP//t+8SkTC1QxzYD4lJT+8PVuwz1mZk/VsN45qgYvFclOtgAuxhfpVuwq58f1WAOPWBfAZX9vmEwoqXhVgTxEfS+0c2qq/mdJ+xKSExsTmcOHz21zCY80YfN1z2zKeRPzTcH8iFfCXsn9UwHdzffJ48J+iJguQvf+JGt2LjHnVs9AWhjyxTY48fcAfO4ZCW4UfUm1/YZk0ScEk7Q32qBceYhrYxyNWeeMFNPX2IuJwqZS08ynKX4SB4v45zVaZqamgoZqTIQu0c2SwnB7RtS7KudQYsbg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=6LgXssEWVoYIjhe5OlZ7SI+3q2Jvn/d0hgCkSXoVxwg=; b=ZvTPUepoPKt8cfHuqspVTpW8iyHtMOkHjU75LhOaXbJqw7Bj8BUxCgXCAErzz6L4npcjvUMbsBxNr6aIlZiX0cSi/xsQfZPXynx2CcizAz1DJfy2I58mtXBTFUtUuHn5V4cqRL1MOV1+gvENSSaJivR9IAECewI+VxElXmhVXEal9Un12eU6/kKl0EDBP+Vq9jP+4bJogW0WzueTqB14CqU8tx2/cJZ9d9japIJfuD5peD8YWAjlKzWbRZjdg1wIZ/Nm/jKiva2yYmoXvgsJVKktr8rtfFF+Bvdo6e/yJQSbiettJYvthE/38xSJeDsGQufV+9E58OtEe//eEZxrUw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=virtuozzo.com; dmarc=pass action=none header.from=openvz.org; dkim=pass header.d=openvz.org; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=virtuozzo.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=6LgXssEWVoYIjhe5OlZ7SI+3q2Jvn/d0hgCkSXoVxwg=; b=TWkpzh2CQ6Q5oV3JQRAsdMMVqQmh3BD56YZD8qm3ERb/8Jf5U2/s2BlgrOBytmvhJeumtMy7IjG5/qlJojdkHA4aAwdDIoRMIePFbEEcD1GPq7veI1uTl6zyhuxu0GURTSRzxdDzzhgcKOzTD8SvbQP6v3YSjxKHhcloMAKXdFA= Authentication-Results: virtuozzo.com; dkim=none (message not signed) header.d=none;virtuozzo.com; dmarc=none action=none header.from=openvz.org; Received: from AM6PR08MB4214.eurprd08.prod.outlook.com (2603:10a6:20b:8d::30) by AM6PR08MB4581.eurprd08.prod.outlook.com (2603:10a6:20b:83::25) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3088.18; Wed, 10 Jun 2020 19:01:49 +0000 Received: from AM6PR08MB4214.eurprd08.prod.outlook.com ([fe80::821:7596:cf7f:68f8]) by AM6PR08MB4214.eurprd08.prod.outlook.com ([fe80::821:7596:cf7f:68f8%4]) with mapi id 15.20.3088.018; Wed, 10 Jun 2020 19:01:49 +0000 Subject: Re: [PATCH 2/2] qcow2: improve savevm performance - please ignore To: qemu-block@nongnu.org, qemu-devel@nongnu.org References: <20200610185833.10665-1-den@openvz.org> <20200610185833.10665-2-den@openvz.org> From: "Denis V. Lunev" Message-ID: Date: Wed, 10 Jun 2020 22:01:46 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 In-Reply-To: <20200610185833.10665-2-den@openvz.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US X-ClientProxiedBy: HE1PR05CA0381.eurprd05.prod.outlook.com (2603:10a6:7:94::40) To AM6PR08MB4214.eurprd08.prod.outlook.com (2603:10a6:20b:8d::30) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from [192.168.1.27] (31.148.204.195) by HE1PR05CA0381.eurprd05.prod.outlook.com (2603:10a6:7:94::40) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3088.18 via Frontend Transport; Wed, 10 Jun 2020 19:01:48 +0000 X-Originating-IP: [31.148.204.195] X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 59874d01-d4e5-4c22-8bb5-08d80d70ba7b X-MS-TrafficTypeDiagnostic: AM6PR08MB4581: X-MS-Exchange-Transport-Forked: True X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:3173; X-Forefront-PRVS: 0430FA5CB7 X-MS-Exchange-SenderADCheck: 1 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: rSrY2V+aBq672Jb3/Vn0sRCdK184kJhb67+JAKK/kqwwiJ2yYWp/fYGWwjnd0kgg/RvEVBzM3Cq5g0voLMvnP8qY/8nezxa2GeMr5sYtLpkcuPYt/62CgK+BSYHTq0JI8WySnBiACftIRVo6tAQ7+1nIeUoWCqMqzkaLcSITVlxsrfJlcnnNEEXUMzSedg4yXujmbBNTUyi53D4ju4qprGb3ZDOQgoWF+5AnxAPWbBB9d7QTwtE6eu7L5FDrPxSLtKrC3tntkdlDj6CJXtybglo3yum2Xy+0zYkgKViaxdhKBdXCgrWDVWe80DU+NJ8A00XgRqGzZ52YK2hzJ7rlFlkuD8NQxjPoz16Iv6gvTK7UTG+M+hvOdghDHw4a/WGA X-Forefront-Antispam-Report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:AM6PR08MB4214.eurprd08.prod.outlook.com; PTR:; CAT:NONE; SFTY:; SFS:(4636009)(366004)(39850400004)(136003)(396003)(376002)(346002)(52116002)(66476007)(66946007)(42882007)(66556008)(53546011)(6486002)(2616005)(956004)(4326008)(2906002)(5660300002)(36756003)(19627235002)(478600001)(186003)(8676002)(107886003)(8936002)(83170400001)(316002)(54906003)(31686004)(16526019)(26005)(83380400001)(16576012)(31696002)(43740500002); DIR:OUT; SFP:1102; X-MS-Exchange-AntiSpam-MessageData: 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 X-OriginatorOrg: openvz.org X-MS-Exchange-CrossTenant-Network-Message-Id: 59874d01-d4e5-4c22-8bb5-08d80d70ba7b X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Jun 2020 19:01:49.0441 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 0bc7f26d-0264-416e-a6fc-8352af79c58f X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: fKDEtbJQ1frvtvauHKXjQAna4+IKDwsLaXV/zZGcRs++sgu/v15nuwWF31BsBenNaDzQPYnrASUcfPNzs+N7Nw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM6PR08MB4581 Received-SPF: pass client-ip=40.107.20.119; envelope-from=den@virtuozzo.com; helo=EUR05-DB8-obe.outbound.protection.outlook.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/10 15:01:49 X-ACL-Warn: Detected OS = Windows NT kernel [generic] [fuzzy] X-Spam_score_int: -26 X-Spam_score: -2.7 X-Spam_bar: -- X-Spam_report: (-2.7 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_EF=-0.1, HEADER_FROM_DIFFERENT_DOMAINS=1, MSGID_FROM_MTA_HEADER=0.001, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=-1, SPF_HELO_PASS=-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: , Cc: Kevin Wolf , Vladimir Sementsov-Ogievskiy , Denis Plotnikov , Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 6/10/20 9:58 PM, Denis V. Lunev wrote: > This patch does 2 standard basic things: > - it creates intermediate buffer for all writes from QEMU migration code > to QCOW2 image, > - this buffer is sent to disk asynchronously, allowing several writes to > run in parallel. > > In general, migration code is fantastically inefficent (by observation), > buffers are not aligned and sent with arbitrary pieces, a lot of time > less than 100 bytes at a chunk, which results in read-modify-write > operations with non-cached operations. It should also be noted that all > operations are performed into unallocated image blocks, which also suffer > due to partial writes to such new clusters. > > Snapshot creation time (2 GB Fedora-31 VM running over NVME storage): > original fixed > cached: 1.79s 1.27s > non-cached: 3.29s 0.81s > > The difference over HDD would be more significant :) > > Signed-off-by: Denis V. Lunev > CC: Kevin Wolf > CC: Max Reitz > CC: Vladimir Sementsov-Ogievskiy > CC: Denis Plotnikov > --- > block/qcow2.c | 111 +++++++++++++++++++++++++++++++++++++++++++++++++- > block/qcow2.h | 4 ++ > 2 files changed, 113 insertions(+), 2 deletions(-) > > diff --git a/block/qcow2.c b/block/qcow2.c > index 0cd2e6757e..e6232f32e2 100644 > --- a/block/qcow2.c > +++ b/block/qcow2.c > @@ -4797,11 +4797,43 @@ static int qcow2_make_empty(BlockDriverState *bs) > return ret; > } > > + > +typedef struct Qcow2VMStateTask { > + AioTask task; > + > + BlockDriverState *bs; > + int64_t offset; > + void *buf; > + size_t bytes; > +} Qcow2VMStateTask; > + > +typedef struct Qcow2SaveVMState { > + AioTaskPool *pool; > + Qcow2VMStateTask *t; > +} Qcow2SaveVMState; > + > static coroutine_fn int qcow2_co_flush_to_os(BlockDriverState *bs) > { > BDRVQcow2State *s = bs->opaque; > + Qcow2SaveVMState *state = s->savevm_state; > int ret; > > + if (state != NULL) { > + aio_task_pool_start_task(state->pool, &state->t->task); > + > + aio_task_pool_wait_all(state->pool); > + ret = aio_task_pool_status(state->pool); > + > + aio_task_pool_free(state->pool); > + g_free(state); > + > + s->savevm_state = NULL; > + > + if (ret < 0) { > + return ret; > + } > + } > + > qemu_co_mutex_lock(&s->lock); > ret = qcow2_write_caches(bs); > qemu_co_mutex_unlock(&s->lock); > @@ -5098,14 +5130,89 @@ static int qcow2_has_zero_init(BlockDriverState *bs) > } > } > > + > +static coroutine_fn int qcow2_co_vmstate_task_entry(AioTask *task) > +{ > + int err = 0; > + Qcow2VMStateTask *t = container_of(task, Qcow2VMStateTask, task); > + > + if (t->bytes != 0) { > + QEMUIOVector local_qiov; > + qemu_iovec_init_buf(&local_qiov, t->buf, t->bytes); > + err = t->bs->drv->bdrv_co_pwritev_part(t->bs, t->offset, t->bytes, > + &local_qiov, 0, 0); > + } > + > + qemu_vfree(t->buf); > + return err; > +} > + > +static Qcow2VMStateTask *qcow2_vmstate_task_create(BlockDriverState *bs, > + int64_t pos, size_t size) > +{ > + BDRVQcow2State *s = bs->opaque; > + Qcow2VMStateTask *t = g_new(Qcow2VMStateTask, 1); > + > + *t = (Qcow2VMStateTask) { > + .task.func = qcow2_co_vmstate_task_entry, > + .buf = qemu_blockalign(bs, size), > + .offset = qcow2_vm_state_offset(s) + pos, > + .bs = bs, > + }; > + > + return t; > +} > + > static int qcow2_save_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, > int64_t pos) > { > BDRVQcow2State *s = bs->opaque; > + Qcow2SaveVMState *state = s->savevm_state; > + Qcow2VMStateTask *t; > + size_t buf_size = MAX(s->cluster_size, 1 * MiB); > + size_t to_copy; > + size_t off; > > BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_SAVE); > - return bs->drv->bdrv_co_pwritev_part(bs, qcow2_vm_state_offset(s) + pos, > - qiov->size, qiov, 0, 0); > + > + if (state == NULL) { > + state = g_new(Qcow2SaveVMState, 1); > + *state = (Qcow2SaveVMState) { > + .pool = aio_task_pool_new(QCOW2_MAX_WORKERS), > + .t = qcow2_vmstate_task_create(bs, pos, buf_size), > + }; > + > + s->savevm_state = state; > + } > + > + if (aio_task_pool_status(state->pool) != 0) { > + return aio_task_pool_status(state->pool); > + } > + > + t = state->t; > + if (t->offset + t->bytes != qcow2_vm_state_offset(s) + pos) { > + /* Normally this branch is not reachable from migration */ > + return bs->drv->bdrv_co_pwritev_part(bs, > + qcow2_vm_state_offset(s) + pos, qiov->size, qiov, 0, 0); > + } > + > + off = 0; > + while (1) { > + to_copy = MIN(qiov->size - off, buf_size - t->bytes); > + qemu_iovec_to_buf(qiov, off, t->buf + t->bytes, to_copy); > + t->bytes += to_copy; > + if (t->bytes < buf_size) { > + return 0; > + } > + > + aio_task_pool_start_task(state->pool, &t->task); > + > + pos += to_copy; > + off += to_copy; > + state->t = t = qcow2_vmstate_task_create(bs, pos, buf_size); > + } > + > + return 0; > } > > static int qcow2_load_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, > diff --git a/block/qcow2.h b/block/qcow2.h > index 7ce2c23bdb..146cfed739 100644 > --- a/block/qcow2.h > +++ b/block/qcow2.h > @@ -291,6 +291,8 @@ typedef struct Qcow2BitmapHeaderExt { > > #define QCOW2_MAX_THREADS 4 > > +typedef struct Qcow2SaveVMState Qcow2SaveVMState; > + > typedef struct BDRVQcow2State { > int cluster_bits; > int cluster_size; > @@ -384,6 +386,8 @@ typedef struct BDRVQcow2State { > * is to convert the image with the desired compression type set. > */ > Qcow2CompressionType compression_type; > + > + Qcow2SaveVMState *savevm_state; > } BDRVQcow2State; > > typedef struct Qcow2COWRegion { - please ignore