Multi-Path Bound for DAG Tasks

Qingqiang He; Nan Guan; Shuai Zhao; Mingsong Lv

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arXiv · 2310.15471

Multi-Path Bound for DAG Tasks

Qingqiang He·Nan Guan·Shuai Zhao·Mingsong Lv

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Abstract

This paper studies the response time bound of a DAG (directed acyclic graph) task. Recently, the idea of using multiple paths to bound the response time of a DAG task, instead of using a single longest path in previous results, was proposed and leads to the so-called multi-path bound. Multi-path bounds can greatly reduce the response time bound and significantly improve the schedulability of DAG tasks. This paper derives a new multi-path bound and proposes an optimal algorithm to compute this bound. We further present a systematic analysis on the dominance and the sustainability of three existing multi-path bounds and the proposed multi-path bound. Our bound theoretically dominates and empirically outperforms all existing multi-path bounds. What's more, the proposed bound is the only multi-path bound that is proved to be self-sustainable.

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BibTeX RIS

Qingqiang He, Nan Guan, Shuai Zhao, Mingsong Lv. 2023-10-24. Multi-Path Bound for DAG Tasks. https://arxiv.org/abs/2310.15471

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