From patchwork Thu Apr 1 07:47:28 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Rao, Lei" X-Patchwork-Id: 12177489 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 44AC6C433ED for ; Thu, 1 Apr 2021 08:13:39 +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 E8DEF61005 for ; Thu, 1 Apr 2021 08:13:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E8DEF61005 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]:38422 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lRsSQ-0007SV-3D for qemu-devel@archiver.kernel.org; Thu, 01 Apr 2021 04:13:38 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:34560) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lRsQ1-0002k1-Oh for qemu-devel@nongnu.org; Thu, 01 Apr 2021 04:11:09 -0400 Received: from mga03.intel.com ([134.134.136.65]:13082) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lRsPz-00067j-SE for qemu-devel@nongnu.org; Thu, 01 Apr 2021 04:11:09 -0400 IronPort-SDR: vmTsYzo+znR32h4mFnT9L9fdQ2DFEyCCkABF2Ik6TD5h2/789KeWDUzbN9aWjUO1NQe9vhYHIr 7wgo7+bFoHtQ== X-IronPort-AV: E=McAfee;i="6000,8403,9940"; a="192205151" X-IronPort-AV: E=Sophos;i="5.81,296,1610438400"; d="scan'208";a="192205151" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Apr 2021 01:11:06 -0700 IronPort-SDR: /c6H/bAyzP7aU+9Hgi8XQgSW3Da4niUmKVdcT/t/sl4hdQPZk2CSrgH7NaURfFF8HLmdGRNpWM k6iEPvfHtdtg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.81,296,1610438400"; d="scan'208";a="439119235" Received: from unknown (HELO localhost.localdomain.bj.intel.com) ([10.240.192.103]) by fmsmga004.fm.intel.com with ESMTP; 01 Apr 2021 01:11:03 -0700 From: leirao To: chen.zhang@intel.com, lizhijian@cn.fujitsu.com, jasowang@redhat.com, quintela@redhat.com, dgilbert@redhat.com, pbonzini@redhat.com, lukasstraub2@web.de Subject: [PATCH v5 09/10] Add the function of colo_bitmap_clear_dirty Date: Thu, 1 Apr 2021 15:47:28 +0800 Message-Id: <1617263249-54501-10-git-send-email-lei.rao@intel.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1617263249-54501-1-git-send-email-lei.rao@intel.com> References: <1617263249-54501-1-git-send-email-lei.rao@intel.com> Received-SPF: pass client-ip=134.134.136.65; envelope-from=lei.rao@intel.com; helo=mga03.intel.com 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, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no 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: "Rao, Lei" , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: "Rao, Lei" When we use continuous dirty memory copy for flushing ram cache on secondary VM, we can also clean up the bitmap of contiguous dirty page memory. This also can reduce the VM stop time during checkpoint. The performance test for COLO as follow: Server configuraton: CPU :Intel(R) Xeon(R) Gold 6140 CPU @ 2.30GHz MEM :251G(type:DDR4 Speed:2666 MT/s) SSD :Intel 730 and DC S35x0/3610/3700 Series SSDs dirty pages:3189376 migration_bitmap_clear_dirty time consuming(ns):105194000 dirty pages:3189784 migration_bitmap_clear_dirty time consuming(ns):105297000 dirty pages:3190501 migration_bitmap_clear_dirty time consuming(ns):105410000 dirty pages:3188734 migration_bitmap_clear_dirty time consuming(ns):105138000 dirty pages:3189464 migration_bitmap_clear_dirty time consuming(ns):111736000 dirty pages:3188558 migration_bitmap_clear_dirty time consuming(ns):105079000 dirty pages:3239489 migration_bitmap_clear_dirty time consuming(ns):106761000 dirty pages:3190240 colo_bitmap_clear_dirty time consuming(ns):8369000 dirty pages:3189293 colo_bitmap_clear_dirty time consuming(ns):8388000 dirty pages:3189171 colo_bitmap_clear_dirty time consuming(ns):8641000 dirty pages:3189099 colo_bitmap_clear_dirty time consuming(ns):8280000 dirty pages:3189974 colo_bitmap_clear_dirty time consuming(ns):8352000 dirty pages:3189471 colo_bitmap_clear_dirty time consuming(ns):8348000 dirty pages:3189681 colo_bitmap_clear_dirty time consuming(ns):8426000 it can be seen from the data that colo_bitmap_clear_dirty is more efficient. Signed-off-by: Lei Rao --- migration/ram.c | 36 +++++++++++++++++++++++++++++++----- 1 file changed, 31 insertions(+), 5 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index 317fa4e..570ffa4 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -857,6 +857,36 @@ unsigned long colo_bitmap_find_dirty(RAMState *rs, RAMBlock *rb, return first; } +/** + * colo_bitmap_clear_dirty:when we flush ram cache to ram, we will use + * continuous memory copy, so we can also clean up the bitmap of contiguous + * dirty memory. + */ +static inline bool colo_bitmap_clear_dirty(RAMState *rs, + RAMBlock *rb, + unsigned long start, + unsigned long num) +{ + bool ret; + unsigned long i = 0; + + /* + * Since flush ram cache to ram can only happen on Secondary VM. + * and the clear bitmap always is NULL on destination side. + * Therefore, there is unnecessary to judge whether the + * clear_bitmap needs clear. + */ + QEMU_LOCK_GUARD(&rs->bitmap_mutex); + for (i = 0; i < num; i++) { + ret = test_and_clear_bit(start + i, rb->bmap); + if (ret) { + rs->migration_dirty_pages--; + } + } + + return ret; +} + static inline bool migration_bitmap_clear_dirty(RAMState *rs, RAMBlock *rb, unsigned long page) @@ -3723,11 +3753,7 @@ void colo_flush_ram_cache(void) num = 0; block = QLIST_NEXT_RCU(block, next); } else { - unsigned long i = 0; - - for (i = 0; i < num; i++) { - migration_bitmap_clear_dirty(ram_state, block, offset + i); - } + colo_bitmap_clear_dirty(ram_state, block, offset, num); dst_host = block->host + (((ram_addr_t)offset) << TARGET_PAGE_BITS); src_host = block->colo_cache