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arXiv · 2505.06645

RTOS Architectures that Solve the Diminishing Bandwidth Problem (with Multi-core Support)

Mazen Arakji
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Abstract

The Diminishing Bandwidth Problem is a long stand-ing, previously unidentified, extensibility problem of current real-time operating systems characterized by a superficial dependency between the number of tasks in a system and the maximum bandwidth associated with an unrelated peripheral device. In the worst case, this diabolical deficiency will continue to decrease the maximum bandwidth of a peripheral device as more tasks are added to the application. If this is not taken into account, a previously functional application may experience data loss if more tasks are added to it in order to, for example, implement new features. Three novel RTOS architectures that solve the Diminishing Bandwidth Problem are specified and discussed: the Defer Structure RTOS Architecture, the Barriers and Requests RTOS Architecture, and the Strictly Atomic RTOS Architecture. Finally, two hardware solutions to the Diminishing Bandwidth Problem are also presented.

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Mazen Arakji. 2025-05-10. RTOS Architectures that Solve the Diminishing Bandwidth Problem (with Multi-core Support). https://arxiv.org/abs/2505.06645

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