Characterizing chip-multiprocessor variability-tolerance

ABSTRACT

Spatially-correlated intra-die process variations result in significant core-to-core frequency variations in chip-multiprocessors. An analytical model for frequency island chip-multiprocessor throughput is introduced. The improved variability-tolerance of FI-CMPs over their globally-clocked counterparts is quantified across a range of core counts and sizes under constant die area. The benefits are highest for designs consisting of many small cores, with the throughput of a globally-clocked design with 70 small cores increasing by 8.8% when per-core frequency islands are used. The small-core FI-CMP also loses only 7.2% of its nominal performance to process variations, the least among any of the designs.

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INDEX TERMS

Primary Classification:
  C. Computer Systems Organization
  C.4 PERFORMANCE OF SYSTEMS

General Terms:
Design, Performance

Keywords:
chip-multiprocessor, frequency islands, process variability