Robert P. Dick, Ganesh Lakshminarayana, Anand Raghunathan, and Niraj K. JhaDesign Automation Conference, 2000

Reporter: Keng-Mao ChoAdvisor: Prof. Chu-Sing YangDate: 2010/12/02

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Introduction TCP/IP Subsystem Example Anti-Lock Braking Example Energy Analysis Infrastructure Results Conclusions

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Despite the widespread use of, and significant role played by, RTOSs in mobile and low-power embedded systems, little is known about their power consumption characteristics.

This work presents the power profiles for a commercial RTOS, μC/OS, running several applications on an embedded system based on the Fujitsu SPARClite processor.

An RTOS provides a number of services to an embedded system designer.◦ Task management◦ Resource management◦ Interrupt◦ Device deiver◦ …

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Energy consumption information is generally more useful, when optimizing an embedded systems’s battery lifespan, than power consumption information.

This work focuses on understanding and characterizing the power effects of system software rather than on building a new systemlevel power analysis tool.

The authors demonstrate that the RTOS itself can consume a significant amount of power.

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A straightforward implementationof the TCP subsystem.

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A multi-process implementation of the TCP subsystem.

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An energy optimized implementation of the ABS example.

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A straightforward implementationof the ABS example.

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Energy consumption profiles.

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Time consumption profiles.

By analyzing a commercial RTOS, μC/OS, running several applications, the authors have demonstrated that the manner in which the RTOS is used has a significant impact on an embedded system’s power consumption.

Insights derived from RTOS power analysis were used to optimize embedded software power consumption.

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Robert P. Dick, Ganesh Lakshminarayana, Anand Raghunathan, and Niraj K. Jha, “Power Analysis of Embedded Operating Systems,” Design Automation Conference, 2000.

V. Tiwari, S. Malik, and A.Wolfe, “Power analysis of embedded software: A first step towards software power minimization,” IEEE Trans.VLSI Systems, vol. 2, pp. 437–445, Dec. 1994.

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Thank you!

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