The link speed in production datacenters is growing fast, from 1 Gbps to 40 Gbps or even 100 Gbps. However, the buffer size of commodity switches increases slowly, e.g., from 4 MB at 1 Gbps to 16 MB at 100 Gbps, thus significantly outpaced by the link speed. In such extremely shallow-buffered networks, today’s TCP/ECN solutions, such as DCTCP, suffer from either excessive packet losses or significant throughput degradation. Motivated by this, we introduce BCC, ¹ a simple yet effective solution that requires only one more ECN configuration (i.e., shared buffer ECN/RED) at commodity switches. BCC operates upon real-time global shared buffer utilization. When available buffer space suffices, BCC delivers both high throughput and low packet loss rate as prior work; When it gets insufficient, BCC automatically triggers the shared buffer ECN to prevent packet loss at the cost of sacrificing a small amount of throughput. BCC is readily deployable with existing commodity switches. We validate BCC’s efficacy in a 100G testbed and evaluate its performance using extensive simulations. Our results show that BCC maintains low packet loss rate persistently while only slightly degrading throughput when the buffer becomes insufficient. For example, compared to current practice, BCC achieves up to 94.4% lower 99th percentile flow completion time (FCT) for small flows while only degrading average FCT for large flows by up to 3%. ¹

BCC: Buffer-aware Active Queue Management (AQM) scheme for Congestion Control in extremely shallow-buffered datacenters.

中文翻译：

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一个足够的配置就够了：为高速极浅缓冲数据中心节省（DC）TCP

生产数据中心的链接速度正在快速增长，从1 Gbps增长到40 Gbps甚至100 Gbps。但是，商用交换机的缓冲区大小缓慢增加，例如从1 Gbps的4 MB增加到100 Gbps的16 MB，从而大大超过了链接速度。在这样的极浅的缓冲网络中，当今的TCP / ECN解决方案（例如DCTCP）会遭受过多的数据包丢失或吞吐量显着下降的困扰。为此，我们介绍了BCC， ^1个一种简单而有效的解决方案，只需在商用交换机上进行一个以上的ECN配置（即共享缓冲区ECN / RED）即可。BCC根据实时全局共享缓冲区利用率进行操作。当可用缓冲区空间足够时，BCC既可以提供较高的吞吐量，又可以提供较低的丢包率，这是先前的工作；当不足时，BCC会自动触发共享缓冲区ECN，以牺牲少量吞吐量为代价来防止数据包丢失。BCC可以很容易地与现有的商用交换机一起部署。我们在100G测试台上验证了BCC的功效，并使用广泛的仿真评估了其性能。我们的结果表明，BCC持续保持低丢包率，而当缓冲区不足时，吞吐量只会稍微降低。例如，与目前的做法相比，密件抄送达到了94分。 ^1个

密件抄送： 乙面向用户的主动队列管理（AQM）方案 C摄取 C极浅缓冲数据中心中的ontrol。