Load Balancing Across Microservices

Yipei Niu, Fangming Liu, Zongpeng Li

Abstract: With the advent of cloud container technology, enterprises develop applications through microservices, breaking monolithic software into a suite of small services whose instances run independently in containers. User requests are served by a series of microservices forming a chain, and the chains often share microservices. Existing load balancing strategies either incur significant networking overhead or ignore the competition for shared microservices across chains. Furthermore, typical load balancing solutions leverage a hybrid technique by combining HTTP with message queue to support microservice communications, bringing additional operational complexity. To address these challenges, we propose a chain-oriented load balancing algorithm (COLBA) based solely on message queues, which balances load based on microservice requirements of chains to minimize response time. We model the load balancing problem as a non-cooperative game, and leverage Nash bargaining to coordinate microservice allocation across chains. Employing convex optimization with rounding, we efficiently solve the problem that is proven NP-hard. Extensive trace-driven simulations demonstrate that COLBA reduces the overall average response time at least by 13% compared with existing load balancing strategies.