Gang EDF Scheduling of Parallel Task Systems

  title={Gang EDF Scheduling of Parallel Task Systems},
  author={Shinpei Kato and Yutaka Ishikawa},
  journal={2009 30th IEEE Real-Time Systems Symposium},
  • S. Kato, Y. Ishikawa
  • Published 1 December 2009
  • Computer Science
  • 2009 30th IEEE Real-Time Systems Symposium
The preemptive real-time scheduling of sporadic parallel task systems is studied. We present an algorithm, called Gang EDF, which applies the Earliest Deadline First (EDF) policy to the traditional Gang scheduling scheme. We also provide schedulability analysis of Gang EDF. Specifically, the total amount of interference that is necessary to cause a deadline miss is first identified. The contribution of each task to the interference is then bounded. Finally, verifying that the total amount of… 

Figures from this paper

Analysis Techniques for Supporting Hard Real-Time Sporadic Gang Task Systems
A novel approach combining new lag-based reasoning and executing/non-executing gang interval analysis technique is introduced, which is able to characterize the parallelisminduced idleness, as a key challenge of analyzing gang task schedules.
Optimal Scheduling of Periodic Gang Tasks
The gang scheduling of parallel implicit-deadline periodic task systems upon identical multiprocessor platforms is considered and two DPFAIR (deadline partitioning) algorithms that schedule all jobs in every interval of time delimited by two subsequent deadlines are proposed.
Hard Real-Time Stationary GANG-Scheduling
This paper provides the first schedulability analysis for sporadic constrained-deadline gang task systems and proposes a novel stationary gang scheduling algorithm that outperforms the state-of-the-art.
Virtual Gang Scheduling of Parallel Real-Time Tasks
The novel concept of a virtual gang is introduced: a group of parallel tasks that are scheduled together as a single entity that transforms the original, complex scheduling problem into a form that can be easily implemented and is amenable to exact schedulability analysis, further reducing pessimism.
Bundled Scheduling of Parallel Real-Time Tasks
  • Saud Wasly, R. Pellizzoni
  • Computer Science
    2019 IEEE Real-Time and Embedded Technology and Applications Symposium (RTAS)
  • 2019
A novel task model where each task is divided into a sequence of segments called bundles, each requiring a different number of cores, and the threads within each bundle are gang scheduled on an identical multiprocessor is introduced, which can significantly improve schedulability compared to the rigid model.
Gang FTP scheduling of periodic and parallel rigid real-time tasks
This paper provides an exact schedulability test for Fixed Task Priority (FTP) Gang scheduler sub-classes: Parallelism Monotonic, Idling, Limited Gang, and Limited Slack Reclaiming and studies the predictability of the schedulers.
Partitioned scheduling of parallel real-time tasks on multiprocessor systems
A partitioned scheduling algorithm is proposed which increases the laxity of the parallel segments and therefore the schedulability of tasksets of this model and eliminates the use of job migrations to create a portable algorithm that can be implemented on a standard Linux kernel.
Analysis of Federated and Global Scheduling for Parallel Real-Time Tasks
The federated scheduling algorithm proposed in this paper is a generalization of partitioned scheduling to parallel tasks and shows that if on unit-speed cores, a task set has total utilization of at most m and the critical-path length of each task is smaller than its deadline, then Federated scheduling can schedule that task set.
On the Decomposition-Based Global EDF Scheduling of Parallel Real-Time Tasks
This paper proposed a new decomposition strategy that better explores the feature of each task, represented by its structure characteristic value, to improve schedulability, and shows that this method consistently outperforms all of the previous methods under different parameter settings.
Conditionally Optimal Task Parallelization for Global EDF on Multi-core Systems
This paper extends the interference-based sufficient schedulability analysis and derives monotonic increasing properties of both tolerance and interference for the Schedulability to propose a one-way search based conditionally optimal algorithm with polynomial time complexity.


Semi-partitioned Scheduling of Sporadic Task Systems on Multiprocessors
A new algorithm for scheduling of sporadic task systems with arbitrary deadlines on identical multiprocessor platforms based on the concept of semi-partitioned scheduling, in which most tasks are fixed to specific processors, while a few tasks migrate across processors.
Global EDF-Based Scheduling with Efficient Priority Promotion
  • S. Kato, N. Yamasaki
  • Business
    2008 14th IEEE International Conference on Embedded and Real-Time Computing Systems and Applications
  • 2008
This paper presents an algorithm, called Earliest Deadline Critical Laxity (EDCL), for the efficient scheduling of sporadic real-time tasks on multiprocessors systems and demonstrates the effectiveness of EDCL in terms of guaranteed schedulability and exhaustive Schedulability by comparing with traditional efficient scheduling algorithms.
An analysis of EDF schedulability on a multiprocessor
  • T. Baker
  • Computer Science
    IEEE Transactions on Parallel and Distributed Systems
  • 2005
A new schedulability test is derived for preemptive deadline scheduling of periodic or sporadic real-time tasks on a single-queue m-server system, and the conclusion that EDF-US[1/2] is optimal, with a guaranteed worst-case schedulable utilization of (m +1)/2.
Multiprocessor EDF and deadline monotonic schedulability analysis
  • T. Baker
  • Computer Science
    RTSS 2003. 24th IEEE Real-Time Systems Symposium, 2003
  • 2003
Schedulability tests are presented for preemptive earlier-deadline-first and deadline-monotonic scheduling of periodic or sporadic real-time tasks on a single-queue m-server system, in which the
Scheduling Arbitrary-Deadline Sporadic Task Systems on Multiprocessors
A new algorithm is proposed for scheduling preemptible arbitrary-deadline sporadic task systems upon multiprocessor platforms, with interprocessor migration permitted, and it is proved to offer superior performance guarantees in comparison to prior feasibility tests.
Optimal Scheduling for Real-Time Parallel Tasks
This letter proves the optimality of the proposed optimal algorithm for the real-time scheduling of parallel tasks on multiprocessors, and shows that the time complexity of the algorithm is O(M2 · N2) in the worst case.
Scheduling parallelizable jobs on multiprocessors
  • C. Han, Kwei-Jay Lin
  • Computer Science, Business
    [1989] Proceedings. Real-Time Systems Symposium
  • 1989
The effect of parallel execution on the complexity of scheduling hard real time jobs on multiprocessors is analyzed and the NP-hardness of scheduling parallelizable jobs where each job has a fixed priority is proved.
A New Approach for Scheduling of Parallelizable Tasks in Real-Time Multiprocessor Systems
It is found that the schedulability offered by parallelizable task scheduling is always higher than that of the EDF algorithm for a wide variety of task parameters and the storage overhead incurred by it is less than 3.6% of the static table-driven approach even under heavy task loads.
Integrating job parallelism in real-time scheduling theory
Improved schedulability analysis of EDF on multiprocessor platforms
This paper introduces a new schedulability test that improves significantly the percentage of accepted task sets, especially when considering task sets containing heavy tasks, and shows the effectiveness of the proposed test through an extensive set of experiments.