The Case for Determinism on the Edge

Emerging edge applications, such as augmented and virtual reality, real-time video analytics and thin-client gaming, are latency-sensitive, resource-intensive, and stateful. Transitioning these applications from cloud deployments to the edge is non-trivial since edge deployments will exhibit variable resource availability, significant user mobility, and high potential for faults and application preemption, requiring considerable developer effort per application to maintain stable quality of experience for the user.

In this paper, we propose deterministic containers, a new abstraction that simplifies the development of complex applications on the edge. Deterministic containers enforce the property that all activity within a container behave deterministically. Determinism provides replication, which in turn provides key benefits for edge computing including resilience to performance jitter, enhanced fault-tolerance, seamless migration, and data provenance.

We are currently building a prototype, Shadow, that aims to provide deterministic containers with minimal performance overhead while requiring few application modifications. For all sources of non-determinism, Shadow either converts the behavior to be deterministic or restricts the allowable application behavior. Preliminary results indicate that using Shadow to reduce performance jitter at the edge for a vehicle caravan application involving video analytics reduces median application response time by up to 25%.