Microscaler: Automatic Scaling for Microservices with an Online Learning Approach

Recently, the microservice becomes a popular architecture to construct cloud native systems due to its agility. In cloud native systems, autoscaling is a core enabling technique to adapt to workload changes by scaling out/in. However, it becomes a challenging problem in a microservice system, since such a system usually comprises a large number of different micro services with complex interactions. When bursty and unpredictable workloads arrive, it is difficult to pinpoint the scaling-needed services which need to scale and evaluate how much resource they need. In this paper, we present a novel system named Microscaler to automatically identify the scaling-needed services and scale them to meet the service level agreement (SLA) with an optimal cost for micro-service systems. Microscaler collects the quality of service metrics (QoS) with the help of the service mesh enabled infrastructure. Then, it determines the under-provisioning or over-provisioning services with a novel criterion named service power. By combining an online learning approach and a step-by-step heuristic approach, Microscaler could achieve the optimal service scale satisfying the SLA requirements. The experimental evaluations in a micro-service benchmark show that Microscaler converges to the optimal service scale faster than several state-of-the-art methods.