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Real-Time Systems

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23.02.2018

Patmos: a time-predictable microprocessor

verfasst von: Martin Schoeberl, Wolfgang Puffitsch, Stefan Hepp, Benedikt Huber, Daniel Prokesch

Erschienen in: Real-Time Systems | Ausgabe 2/2018

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Abstract

Current processors provide high average-case performance, as they are optimized for general purpose computing. However, those optimizations often lead to a high worst-case execution time (WCET). WCET analysis tools model the architectural features that increase average-case performance. To keep analysis complexity manageable, those models need to abstract from implementation details. This abstraction further increases the WCET bound. This paper presents a way out of this dilemma: a processor designed for real-time systems. We design and optimize a processor, called Patmos, for low WCET bounds rather than for high average-case performance. Patmos is a dual-issue, statically scheduled RISC processor. A method cache serves as the cache for the instructions and a split cache organization simplifies the WCET analysis of the data cache. To fill the dual-issue pipeline with enough useful instructions, Patmos relies on a customized compiler. The compiler also plays a central role in optimizing the application for the WCET instead of average-case performance.

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Titel: Patmos: a time-predictable microprocessor
verfasst von: Martin Schoeberl
Wolfgang Puffitsch
Stefan Hepp
Benedikt Huber
Daniel Prokesch
Publikationsdatum: 23.02.2018
Verlag: Springer US
Erschienen in: Real-Time Systems / Ausgabe 2/2018
Print ISSN: 0922-6443
Elektronische ISSN: 1573-1383
DOI: https://doi.org/10.1007/s11241-018-9300-4

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