ENL Publications

Abstract

Kevin Klues, Chieh-Jan Liang, Jeongyeup Paek, Razvan Musaloiu-E, Phil Levis, Andreas Terzis, Ramesh Govindan, TOSThreads: Thread-Safe and Non-Invasive Preemption in TinyOS, In Proceedings of the 7th ACM Conference on Embedded Networked Sensor Systems (SenSys'09), November 2009. [PDF] [BIB]

Many threads packages have been proposed for programming wireless sensor platforms. However, many sensor network operating systems still choose to provide an event-driven model, due to efficiency concerns. We present TOSThreads, a threads package for TinyOS that combines the ease of a threaded programming model with the efficiency of an event-based kernel. TOSThreads is backwards compatible with existing TinyOS code, supports an evolvable, thread-safe kernel API, and enables flexible application development through dynamic linking and loading. In TOSThreads, TinyOS code runs at a higher priority than application threads and all kernel operations are invoked only via message passing, never directly, ensuring thread-safety while enabling maximal concurrency. The TOSThreads package is non-invasive; it does not require any large-scale changes to existing TinyOS code.
We demonstrate that TOSThreads context switches and system calls introduce an overhead of less than 0.92% and that dynamic linking and loading takes as little as 90 ms for a representative sensing application. We compare different programming models built using TOSThreads, including standard C with blocking system calls and a reimplementation of Tenet. Additionally, we demonstrate that TOSThreads is able to run computationally intensive tasks without adversely affecting the timing of critical OS services.

@inproceedings{Klues09a,
	author = {Kevin Klues and Chieh-Jan Liang and Jeongyeup Paek and Razvan Musaloiu-E and Phil Levis and Andreas Terzis and Ramesh Govindan},
	title = {{TOSThreads: Thread-Safe and Non-Invasive Preemption in TinyOS}},
	booktitle = "{ Proceedings of the 7th ACM Conference on Embedded Networked Sensor Systems (SenSys'09)}",
	year = "2009",
	month = "November",
	location = "Berkeley, CA, USA",
}