Open Access

ARTICLE

A Scheduling Extension Scheme of the Earliest Deadline First Policy for Hard Real-Time Uniprocessor Systems Integrated on Posix Threads Based on Linux

by Vidblain Amaro-Ortega, Arnoldo Díaz-Ramírez, Brenda Leticia Flores-Ríos, Félix Fernando González-Navarro, Frank Werner, Larysa Burtseva

1 Autonomous University of Baja California, Mexico.
E-mail: brenda. ores@uabc.edu.mx, fernando.gonzalez@uabc.edu.mx, burtseva@uabc.edu.mx
2 Technical Institute of Mexicali, Mexico. E-mail: adiaz@itmexicali.edu.mx
3 Otto-von-Guericke University Magdeburg, Germany. E-mail: frank.werner@ovgu.de

* Corresponding Author: E-mail:

Computer Systems Science and Engineering 2018, 33(1), 31-40. https://doi.org/10.32604/csse.2018.33.031

Abstract

The Linux operating system has been employed to execute numerous real-time applications. However, it is limited to support soft real-time systems by two scheduling policies: First-In-First-Out and Round Robin. For real-time systems with critical constraints, the soft real-time support and these scheduling policies are still insufficient. In this work, the Earliest Deadline First scheduling policy, which has been shown in theory to be an optimal one in uniprocessor systems, is introduced as an extension of the Linux kernel. This policy is implemented into the real-time class, without the necessity of defining an additional class. The Linux kernel affords capabilities of a hard real-time operating system by an RT-Preempt patch, enabling the use of Linux to implement hard realtime systems. The integration is compliant with the POSIX real-time and thread standards, ensuring applications portability, employing the GLIBC library. In order to validate the proposed implementation, a set of experiments is conducted, showing that a real-time system that cannot be feasibly scheduled using existing policies, attains feasibility when it is scheduled using the integrated Earliest Deadline First policy.

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Keywords

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