Load balancing in datacenter networks (DCNs) is an important and challenging task for datacenter managers. A number of sophisticated technologies have been proposed to improve load balancing performance in a complicated circumstance, i.e., with various traffic characteristics. Many approaches need a high cost to implement, such as changing switch hardware. The efficiency problem has not been well addressed. MPTCP was proposed as a low-cost approach to improve data transmission in DCNs, which uses subflows to balance workloads across multiple paths. However, current MPTCP is not satisfying, especially when there are rack-local flows or many-to-one short flows. In this article, we propose DCMPTCP to improve the efficacy of MPTCP. We gradually develop three mechanisms. First, DCMPTCP identifies rack-local traffic and eliminates unnecessary subflows to reduce the overhead. Second, DCMPTCP estimates flow length and establishes subflows in a smarter way. Third, DCMPTCP strengthens explicit congestion notification to improve the congestion control performance on inter-rack many-to-one short flows. We have implemented DCMPTCP in both the Linux kernel and ns-3 simulator. Our comprehensive testbed experiments and simulations show that DCMPTCP outperforms MPTCP in both 1 Gbps testbed, and 10 Gbps large-scale simulation network.

中文翻译：

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使用多路径传输和架顶式交换机实现低成本数据中心负载平衡

数据中心网络 (DCN) 中的负载平衡是数据中心管理人员的一项重要且具有挑战性的任务。已经提出了许多复杂的技术来提高复杂环境下的负载均衡性能，即具有各种流量特征。许多方法需要高成本来实施，例如更改交换机硬件。效率问题没有得到很好的解决。MPTCP 被提议作为一种改进 DCN 中数据传输的低成本方法，它使用子流来平衡多条路径上的工作负载。但是，当前的 MPTCP 并不令人满意，尤其是在存在机架本地流或多对一短流时。在本文中，我们提出 DCMPTCP 来提高 MPTCP 的功效。我们逐步发展三种机制。第一的，DCMPTCP 识别机架本地流量并消除不必要的子流以减少开销。其次，DCMPTCP 估计流长度并以更智能的方式建立子流。第三，DCMPTCP 加强了显式拥塞通知，以提高对机架间多对一短流的拥塞控制性能。我们已经在 Linux 内核和 ns-3 模拟器中实现了 DCMPTCP。我们全面的测试平台实验和模拟表明，DCMPTCP 在 1 Gbps 测试平台和 10 Gbps 大规模模拟网络中均优于 MPTCP。我们已经在 Linux 内核和 ns-3 模拟器中实现了 DCMPTCP。我们全面的测试平台实验和模拟表明，DCMPTCP 在 1 Gbps 测试平台和 10 Gbps 大规模模拟网络中均优于 MPTCP。我们已经在 Linux 内核和 ns-3 模拟器中实现了 DCMPTCP。我们全面的测试平台实验和模拟表明，DCMPTCP 在 1 Gbps 测试平台和 10 Gbps 大规模模拟网络中均优于 MPTCP。