HPCC: High Precision Congestion Control


HPCC, a new high-speed CC mechanism, achieves ultra-low latency, high bandwidth, and network stability simultaneously. HPCC leverages in-network telemetry (INT) to obtain precise link load information and controls traffic precisely. HPCC can quickly converge to utilize free bandwidth while avoiding congestion, and can maintain near-zero in-network queues for ultra-low latency.

HPCC has been deployed in Alibaba. It shortens the flow completion times by up to 95% compared to the previous generation CC (DCQCN) for datacenters.

[New] We have recently enhanced HPCC with PINT, a probalistic version of INT that reduces the INT overhead to ≤2 bytes without losing precision for HPCC.



Key results

We post latest results with both INT-based and PINT-based HPCC. We evaluate HPCC comprehensively under different application workload (web search and hadoop) and different network load (30%, 50%, 70%).

Media reports

HPCC is reported by ≥20 different media globally.