Review for "Less is More: Trading a little Bandwidth for Ultra-Low Latency in the Data Center"

The data flow in the network can be categorized into 2 parts, throughput originated applications, and latency sensitive applications. However, the latency sensitive applications need a man in the loop and the completion time is slow. Therefore, the network is not optimized with for latency or predictable packet delivery.

The author proposes HULL (High bandwidth Ultra Low Latency), a system that can ensure deliver ultra-low latency packet and high bandwidth utilization in a shared data center fabric. The observation here is it is possible to reduce or eliminate network buffering. Given this, the author cap the bandwidth and trade for low latency.

The nugget of HULL is to trade bandwidth with latency in the network. They leverage pacer module to place space between the packets of large flow. And it also implement a dynamic pacing rate estimation function to adjust pacing dynamically.

The previous works mainly focus on bandwidth provisioning for achieving low latency. On the contrary, HULL is try to sacrifice some bandwidth in order to achieve low latency.

The trade off here is of course the lower bandwidth utility in HULL.

I think the idea is interesting. And it maybe influential in 10 years.