Low-latency transport protocols inactor systems : Performance evaluation of QUIC in Kompact

Sammanfattning: Developers widely use actor frameworks to build highly distributed systems. However, modern actor frameworks are limited in their network implementations, with Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) being the main protocols used for network communication. This thesis investigates the use of specialized network protocols to improve the performance of actor frameworks in distributed systems. Message-passing, while commonly based on TCP, needs more performance and security than other protocols; therefore, the focus will be on different low-latency transport protocols that could substitute TCP. This work examines actor communication at the transport layer, considering the constraints of the deployment that often dictate the choice of a transport protocol. We explore how Quick UDP Internet Connections (QUIC), a low-latency transport protocol, affects actor systems performance and reliability by investigating the benefits of replacing TCP with QUIC in Kompact, a component-actor hybrid framework. We provide an overview of other low-latency protocols that fit various actor frameworks and implement QUIC in the networking layer of Kompact. Thereof, we evaluate the performance of QUIC, UDP and TCP in two different scenarios, such as file transfers outside of actor systems and ping-pong latency measurements within Kompact. The results show that glsquic outperforms TCP for larger file transfers outside actor systems, accomplishing higher throughput and faster download times. However, in the Kompact benchmark, QUIC did not outperform TCP due to issues with QUIC’s event loop implementation. The study also highlights the importance of proper synchronization between event loops in distributed systems. The findings suggest that QUIC has the potential to improve performance and reliability in actor systems by reducing latency and enhancing reliability through features such as multiplexing and connection migration.