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Title: Power Clocks: Dynamic Multi-Clock Management for Embedded Systems
This paper presents Power Clocks, a kernel-based dy- namic clock management system that reduces active en- ergy use in embedded microcontrollers by changing the clock based on ongoing computation and I/O requests. In Power Clocks, kernel hardware drivers asynchronously re- quest clocks, providing a set of constraints (e.g., maximum speed), which the kernel uses to dynamically choose the most efficient clock. To select a clock, Power Clocks makes use of the observation that though slower clocks use less power and are suited for fixed time I/O operations, faster clocks use less energy per clock tick, making them opti- mal for pure computation. Using Power Clocks, a networked sensing application consumes 27% less energy than the best static clock, and within 3% of an optimal hand-tuned dy- namic clock strategy. Power Clocks provides similar energy savings even when there are multiple applications.  more » « less
Award ID(s):
1931750
PAR ID:
10292320
Author(s) / Creator(s):
Date Published:
Journal Name:
6th Annual International Conference on Distributed Computing in Sensor Systems (DCOSS 2020)
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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