Many important cloud services require replicating massive data from one datacenter (DC) to multiple DCs. While the performance of pair-wise inter-DC data transfers has been much improved, prior solutions are insufficient to optimize bulk-data multicast, as they fail to explore the rich inter-DC overlay paths that exist in geo-distributed DCs, as well as the remaining bandwidth reserved for online traffic under fixed bandwidth separation scheme. To take advantage of these opportunities, we present BDS+ , a near-optimal network system for large-scale inter-DC data replication. BDS+ is an application-level multicast overlay network with a fully centralized architecture, allowing a central controller to maintain an up-to-date global view of data delivery status of intermediate servers, in order to fully utilize the available overlay paths. Furthermore, in each overlay path, it leverages dynamic bandwidth separation to make use of the remaining available bandwidth reserved for online traffic. By constantly estimating online traffic demand and rescheduling bulk-data transfers accordingly, BDS+ can further speed up the massive data multicast. Through a pilot deployment in one of the largest online service providers and large-scale real-trace simulations, we show that BDS+ can achieve 3- $5\times $ speedup over the provider’s existing system and several well-known overlay routing baselines of static bandwidth separation. Moreover, dynamic bandwidth separation can further reduce the completion time of bulk data transfers by 1.2 to 1.3 times.

中文翻译：

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BDS +：具有动态带宽分离的数据中心间数据复制系统

许多重要的云服务需要将海量数据从一个数据中心（DC）复制到多个DC。尽管成对的DC间数据传输的性能已大大提高，但现有的解决方案不足以优化批量数据多播，因为它们也无法探索地理分布DC中存在的丰富的DC间覆盖路径。作为固定带宽分离方案下为在线流量保留的剩余带宽。为了利用这些机会，我们提出BDS + ，这是用于大规模DC间数据复制的近乎最佳的网络系统。BDS +是具有以下功能的应用程序级组播覆盖网络：完全集中架构，允许中央控制器维护中间服务器数据传输状态的最新全局视图，以便充分利用可用的覆盖路径。此外，在每个覆盖路径中，它利用动态带宽分离来利用为在线流量保留的剩余可用带宽。通过不断估计在线流量需求并相应地重新安排批量数据传输，BDS +可以进一步加快海量数据多播的速度。通过在最大的在线服务提供商之一中进行试点部署以及大规模的实际跟踪模拟，我们证明BDS +可以实现3- $ 5 \次$ 加速了提供商现有系统和静态带宽分离的几个众所周知的覆盖路由基准。此外，动态带宽分离可以进一步将批量数据传输的完成时间减少1.2到1.3倍。