Caching Single-Assignment Structures to Build a Robust Fine-Grain Multi-Threading System

We present the design, implementation, and evaluation of single assignment data structures and of a software controlled cache in an existing multi-threaded architecture platform { the E cient Architecture for Running Threads (EARTH). In EARTH, split-phase operations enable the tolerance of remote communication latency by a decoupling between the initiators and the receivers of communication/synchronization transactions. Under EARTH, the requester and receiver of a split-phase transaction are actually placed in separate threads. We focus on split-phase memory operations under a global shared address space. A software-controlled cache is proposed to exploit the temporal and spatial locality of singleassignment structure memory references. Our experimental evaluation using a set of benchmarks indicates that the EARTH system with both the single-assignment storage and its caching mechanism is more robust. As a consequence the system can be ported to a wider range of machine platforms and deliver speedup for both regular and irregular application.