Application-Specific Protocols for User-Level Shared Memory

Report ID: TR-464-94
Author: Falsafi, Babak / Lebeck, Alvin / Reinhardt, Steven / Hill, Mark D. / Larus, James R. / Rogers, Anne / Schoinas, Ioannis / Wood, David A.
Date: 1994-08-00
Pages: 10
Download Formats: |Postscript|
Abstract:

Recent distributed shared memory (DSM) systems and proposed shared-memory machines have implemented some or all of their cache coherence protocols in software. One way to exploit the flexibility of this software is to tailor a coherence protocol to match an application's communication patterns and memory semantics. This paper presents evidence that this approach can lead to large performance improvements. It shows that application-specific protocols substantially improved the performance of three application programs--appbt, em3d, and barnes--over carefully tuned transparent shared memory implementations. The speed-ups were obtained on Blizzard, a fine-grained DSM system running on a 32-node Thinking Machines CM-5.