Dagger: Towards Efficient RPCs in Cloud Microservices With Near-Memory Reconfigurable NICs

Cloud applications are increasingly relying on hundreds of loosely-coupled microservices to complete user requests that meet an application's end-to-end QoS requirements. Communication time between services accounts for a large fraction of the end-to-end latency and can introduce performance unpredictability and QoS violations. This letter presents our early work on Dagger, a hardware acceleration platform for networking, designed specifically with the unique qualities of microservices in mind. The Dagger architecture relies on an FPGA-based NIC, closely coupled with the processor over a configurable memory interconnect, designed to offload and accelerate RPC stacks. Unlike the traditional cloud systems that use PCIe links as the NIC I/O interface, we leverage memory-interconnected FPGAs as networking devices to provide the efficiency, transparency, and programmability needed for fine-grained microservices. We show that this considerably improves CPU utilization and performance for cloud RPCs.