Reducing Execution Unit Leakage Power in Embedded Processors

  • Houman Homayoun
  • Amirali Baniasadi
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4017)


We introduce low-overhead power optimization techniques to reduce leakage power in embedded processors. Our techniques improve previous work by a) taking into account idle time distribution for different execution units, and b) using instruction decode and control dependencies to wakeup the gated (but needed) units as soon as possible. We take into account idle time distribution per execution unit to detect an idle time period as soon as possible. This in turn results in increasing our leakage power savings. In addition, we use information already available in the processor to predict when a gated execution unit will be needed again. This results in early and less costly reactivation of gated execution units. We evaluate our techniques for a representative subset of MiBench benchmarks and for a processor using a configuration similar to Intel’s Xscale processor. We show that our techniques reduce leakage power considerably while maintaining performance.


Power Dissipation Basic Block Idle Period Leakage Power Timing Overhead 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Houman Homayoun
    • 1
  • Amirali Baniasadi
    • 1
  1. 1.Electrical and Computer Engineering DepartmentUniversity of VictoriaVictoriaCanada

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