A Power Efficient Speculative Fetch Architectur

Glenn Reinman, Brad Calder and Todd Austin
CS2000-0657
June 28, 2000

Low-power research has flourished recently, in an attempt to address packaging and cooling concerns of current microprocessor designs, as well as battery life for mobile computers. In this paper, we propose and evaluate a high performance, energy efficient front-end architecture. We outline a low-power instruction cache configuration, and examine the benefit of decoupling the tag component of our cache from the data component. This decoupling enables a sophisticated cache replacement algorithm and an accurate, but energy efficient, mechanism for speculative fetching. Cache blocks are initially verified by the tag component of the cache -- those that miss in the cache can be speculatively brought in from lower levels of the memory hierarchy. We introduce and analyze a number of auxiliary structures that enhance this design and maintain consistency between the time of verification and the actual cache block lookup. Our power efficient cache configuration provides a 43% reduction in energy dissipation over a comparable prefetching scheme for the benchmarks we examine, while attaining slightly better performance (measured in instructions per nanosecond).


How to view this document


The authors of these documents have submitted their reports to this technical report series for the purpose of non-commercial dissemination of scientific work. The reports are copyrighted by the authors, and their existence in electronic format does not imply that the authors have relinquished any rights. You may copy a report for scholarly, non-commercial purposes, such as research or instruction, provided that you agree to respect the author's copyright. For information concerning the use of this document for other than research or instructional purposes, contact the authors. Other information concerning this technical report series can be obtained from the Computer Science and Engineering Department at the University of California at San Diego, techreports@cs.ucsd.edu.


[ Search ]


NCSTRL
This server operates at UCSD Computer Science and Engineering.
Send email to webmaster@cs.ucsd.edu