Performance Evaluation of the Orca Shared-Object System

Orca is a portable, object-based distributed shared memory system. This paper studies and evaluates the design choices made in the Orca system and compares Orca with other DSMs. The paper gives a quantitative analysis of Orca’s coherence protocol (based on write-updates with function shipping), the totally-ordered group communication protocol, the strategy for object placement, and the all-software, user-space architecture. Performance measurements for ten parallel applications illustrate the tradeoffs made in the design of Orca, and also show that essentially the right design decisions have been made. A write-update protocol with function shipping is effective for Orca, especially since it is used in combination with techniques that avoid replicating objects that have a low read/write ratio. The overhead of totally-ordered group communication on application performance is low. The Orca system is able to make near-optimal decisions for object placement and replication. In addition, ...

• Type: Journal
• Year: 1998
• Where: TOCS
• Authors: Henri E. Bal, Raoul Bhoedjang, Rutger F. H. Hofman, Ceriel J. H. Jacobs, Koen Langendoen, Tim Rühl
• Keywords: Group Communication, Orca, Performance Measurements, TOCS 1998