UDM: User Direct Messaging for General-Purpose Multiprocessing

Abstract

User Direct Messaging (UDM) allows user-level, processor-to- processor messaging to coexist with general multiprogramming and virtual memory. Direct messaging, where processors launch and receive messages in tens of cycles directly via network interface FIFO's as opposed to indirectly via memory, offers high message bandwidth and low delivery latency by avoiding memory delay and buffer management overhead.