Pagurus: Eliminating Cold Startup in Serverless Computing with Inter-Action Container Sharing

TL;DR

Pagurus is a system that reduces serverless function startup latency by sharing containers among similar actions, effectively eliminating cold start delays and enabling near-instantaneous function invocation.

Contribution

It introduces a novel container sharing approach with inter-action scheduling to eliminate cold start latency in serverless computing.

Findings

Reduces cold start latency to around 10ms

Effectively eliminates long container startup delays

Improves serverless response times significantly

Abstract

Serverless computing provides fine-grain resource sharing between Cloud tenants through containers. Each function invocation (action) runs in an individual container. When there is not an already started container for a user function, a new container has to be created for it. However, the long cold startup time of a container results in the long response latency of the action. Our investigation shows that the containers for some user actions share most of the software packages. If an action that requires a new container can ``borrow'' a similar warm container from other actions, the long cold startup can be eliminated. Based on the above finding, we propose Pagurus, a runtime container management system for eliminating the cold startup in serverless computing. Pagurus is comprised of an inter-action container scheduler and an intra-action container scheduler for each action. The inter-action container scheduler schedules shared containers among actions. The intra-action container scheduler deals with the management of the container lifecycle. Our experimental results show that Pagurus effectively eliminates the time-consuming container cold startup. An action may start to run in 10ms with Pagurus, even if there is not warm container for it.