Best Speed Fit EDF Scheduling for Performance Asymmetric Multiprocessors

Peng Wu,Minsoo Ryu

doi:10.1155/2017/1237438

Abstract

In order to improve the performance of a real-time system, asymmetric multiprocessors have been proposed. The benefits of improved system performance and reduced power consumption from such architectures cannot be fully exploited unless suitable task scheduling and task allocation approaches are implemented at the operating system level. Unfortunately, most of the previous research on scheduling algorithms for performance asymmetric multiprocessors is focused on task priority assignment. They simply assign the highest priority task to the fastest processor. In this paper, we propose BSF-EDF (best speed fit for earliest deadline first) for performance asymmetric multiprocessor scheduling. This approach chooses a suitable processor rather than the fastest one, when allocating tasks. With this proposed BSF-EDF scheduling, we also derive an effective schedulability test.

Highlights

Modern semiconductor technology adopts the use of multiple processors in their motherboard design because of the growing demand of performance and saving energy which cannot be handled by single processor systems
We propose BSF-earliest deadline first (EDF) for performance asymmetric multiprocessor scheduling
The ARM big.LITTLE architectures are already used by Samsung in their Galaxy Note 5 and S6 Edge

Summary

Introduction

Modern semiconductor technology adopts the use of multiple processors in their motherboard design because of the growing demand of performance and saving energy which cannot be handled by single processor systems In this regard, performance asymmetric multiprocessors, where individual cores possess different performance, are believed to provide improved performance and low power consumption when compared to performance symmetric multiprocessors, where the cores are identical [1]. For embedded real-time systems, in addition to resource and power optimization, guaranteeing the deadlines of a realtime system is a critical requirement Scheduling on such a performance asymmetric multicore platform is much more challenging than scheduling on identical multicore platform since the processing speed depends on the processor type, and on the task executed.

System Model and Background

Conclusions