Protocol Buffer Deserialization DPU Offloading in the RPC Datapath

In the microservice paradigm, monolithic applications are decomposed into finer-grained modules invoked independently in a data-flow fashion. The different modules communicate through remote procedure calls (RPCs), which constitute a critical component of the infrastructure. To ensure portable passage of RPC metadata, arguments, and return values between different microservices, RPCs involve serialization/deserialization activities, part of the RPC data center tax. We demonstrate how RPC server logic, including serialization/deserialization, can be offloaded to Data Processing Units (DPUs). This effectively reduces the RPC data center tax on the host, where applications' business logic runs. While we focus on offloading Protocol Buffers deserialization used by the popular gRPC framework, our findings can be applied to other RPC infrastructures. Our experimental results demonstrate that RPC offloading performs similarly to traditional methods while significantly reducing CPU usage.