dCache -- Efficient Message Encoding For Inter-Service Communication

As a well established, large-scale distributed storage system, dCache is required to manage and serve huge amount of data for WLHC experiments and beyond. Based on a microservices-like architecture, dCache is built as a modular system distributed, where each component provides a different core functionality. These services communicate by passing serialized messages of dynamic types to each other, a core behavior whose performance properties can consequently affect the entire system. The usage of Java Object Serialization for encoding messages has increasingly presented as no longer being sufficiently performant. A metric for evaluating message object graph complexity is introduced and the performance of several serialization techniques is evaluated accordingly. The mapping of a dynamic object tree to a fixed format, that can be serialized efficiently, is investigated. In this presentation we introduce the flexible integration of a new message serialization format into dCache, which enables the simultaneous support of different encoding techniques, allowing for a gradual transition.