Micro Congestion Control: Every Flow Deserves a Second Chance

TL;DR

Micro Congestion Control (MCC) is a flexible framework that dynamically assigns and switches between different congestion control algorithms per connection in datacenter environments, adapting to heterogeneity and network dynamics.

Contribution

MCC introduces a novel framework allowing per-connection algorithm assignment and dynamic switching, enhancing adaptability in diverse and changing network conditions.

Findings

MCC can switch algorithms on the fly with smooth transitions.

MCC achieves potential performance improvements in real-world tests.

Overheads of MCC are moderate and acceptable.

Abstract

Today, considerable Internet traffic is sent from the datacenter and heads for users. The characteristics of connections served by servers in datacenters are usually diverse and varied over time, with continuous upgrades in network infrastructure and user devices. As a result, a specific congestion control algorithm hardly accommodates the heterogeneity and performs well in various scenarios. In this work, we present Micro Congestion Control (MCC) --- a novel framework for Internet congestion control. With MCC, diverse algorithms can be assigned purposely to connections in one server to adapt to heterogeneity, and different algorithms can be chosen in each connection's life cycle to keep pace with the dynamic of network. We design and implement MCC in Linux, and the experiments validate that MCC is capable of smoothly switching among various candidate algorithms on the fly to achieve potential performance gain in the real world. Meanwhile, the overheads introduced by MCC are moderate and acceptable.