Zeropod: Simplifying Datacenter Networking with Future-Proof Zero-Buffer Packet Switches

TL;DR

Zeropod introduces a simplified, future-proof datacenter network architecture with zero-buffer switches and centralized scheduling, achieving high performance and low latency by reducing complexity and improving capacity.

Contribution

It proposes Zeropod, a novel datacenter architecture with zero-buffer switches and a hybrid scheduling approach, enhancing capacity and control while simplifying the data plane.

Findings

Zeropod outperforms traditional buffered DCNs in flow completion time.

The architecture enables higher switching capacity due to buffer removal.

Performance improves further when considering increased capacity.

Abstract

With the rapid growth of traffic volume in datacenter networks (DCNs), packet switches suffer from insufficient switching chip capacity and difficulties in transmission control, making it challenging to provide high goodput and low latency for emerging cloud applications. We present Zeropod, a future-proof DCN architecture featuring simplified zero-buffer packet switches inside the point-of-delivery (pod). Within each pod, traffic transmission is scheduled by a per-pod centralized scheduler for collision avoidance, enabling a highly simplified data plane, facilitating benefits like higher switching capacity and precise transmission control. Among the pods, buffered Core switches work as barriers and relay inter-pod data, limiting the scope of centralized scheduling and thus simplifying the control plane. Zeropod combines host-level and flow-level scheduling for high performance with low overhead. Evaluation results show that Zeropod consistently performs better or equivalent to traditional buffered DCN, particularly regarding flow completion time (FCT). When accounting for the increased switching capacity due to the removal of buffers, its performance is further improved. Zeropod explores an extreme end of the design spectrum, and we hope it can encourage further exploration in the DCN community.