|   | CMU-CS-98-171 Computer Science Department
 School of Computer Science, Carnegie Mellon University
 
    
     
 CMU-CS-98-171
 
Extending Cache Coherence to Support Thread-LevelData Speculation on a Single Chip and Beyond
 
J. Gregory Steffan, Christopher B. Colohan, Todd C. Mowry 
December 1998  
CMU-CS-98-171.psCMU-CS-98-171.pdf
 Keywords: Multiple data stream architectures (parallel processors),
cache memories, performance of systems
 Thread-Level Data Speculation (TLDS) is a technique which enables
the optimistic parallelization of applications despite ambiguous
data dependencies between the resulting threads.  Although TLDS is
mostly managed by software, hardware provides two key pieces of 
functionality: (i) detecting dependence violations, and (ii) buffering 
speculative side-effects until they can be safely committed to memory.
To provide this functionality we present an extension to 
invalidation-based cache coherence which is both scalable and has a 
minimal impact on hardware complexity. We explore the design space in 
depth and find that our baseline architecture is sufficient to exploit 
speculative parallelism.
 
22 pages 
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