A Remote Procedure Call Approach for Extreme-scale Services

When working at exascale, the various constraints imposed by the extreme scale of the system bring new challenges for application users and software/middleware developers. In that context, and to provide best performance, resiliency and energy efficiency, software may be provided as a service oriented approach, adjusting resource utilization to best meet facility and user requirements. Remote procedure call (RPC) is a technique that originally followed a client/server model and allowed local calls to be transparently executed on remote resources. RPC consists of serializing the local function parameters into a memory buffer and sending that buffer to a remote target that in turn deserializes the parameters and executes the corresponding function call, returning the result back to the caller. Building reusable services requires the definition of a communication model to remotely access these services and for this purpose, RPC can serve as a foundation for accessing them. We introduce the necessary building blocks to enable this ecosystem to software and middleware developers with an RPC framework called Mercury.