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Hardware Support for Real-time Operating Systems

Authors:
Paul Kohout
Paul Kohout
Paul Kohout
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Brinda Ganesh
Brinda Ganesh
Brinda Ganesh
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Bruce Jacob at University of Maryland Global Campus
Bruce Jacob
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Abstract

The growing complexity of embedded applications and pressure on time-to-market has resulted in the increasing use of embedded real-time operating systems. Unfortunately, RTOSes can introduce a significant performance degradation. The paper presents the Real-Time Task Manager (RTM) - a processor extension that minimizes the performance drawbacks associated with RTOSes. The RTM accomplishes this by supporting, in hardware, a few of the common RTOS operations that are performance bottlenecks: task scheduling, time management, and event management. By exploiting the inherent parallelism of these operations, the RTM completes them in constant time, thereby significantly reducing RTOS overhead. It decreases both the processor time used by the RTOS and the maximum response time by an order of magnitude.
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Full-text available
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