Research On Real-time Hybrid Task Scheduling Algorithm Based On Multi-core Platform

With the development of society,the performance of computer processing which the people demand for is improving.The processing capacity of traditional single-core processor can't meet the needs of some specific applications.The need to improve the performance of computer processing is placed on multiple core processor architecture.Thus multi-core processor came into being.In today's world,multi-core processor is gradually replacing the traditional single-core processor because of its many advantages,and become the mainstream of the market.With the widespread use of multi-core processors,real-time systems have a wider application platform.At the same time,the complexity of real time system is greatly increased.In many cases,different types of tasks can be found in one system,including real-time periodic tasks and real-time sporadic tasks.It has important theoretical significance and practical application value for the research of the real-time scheduling problem for period and sporadic tasks on multi-core processor platform.In the view of improving the average response time of the sporadic task,in this paper,the real-time hybrid task scheduling algorithms with periodic tasks and sporadic task on a multi-core processor platform are studied.First of all,this paper proposes the Earliest Release Time Frist(ERTF)time allocation strategy.And then combining it with the LRE-TL algorithm,this paper proposes an improved LRE-TL algorithm(E-LRE-TL)based on ERTF time allocation strategy.This algorithm allows the reallocation of processor idle time algorithm to solve the large average response time of LRE-TL,while reducing the kernel preemption probability and reducing the scheduling overhead of real-time systems,.E-LRE-TL performs better than previous algorithms.However,it allocates too much processor resources to the real time periodic task scheduling.In order to overcome the shortcomings of the E-LRE-TL algorithm,this paper proposes a E-LRE-TL algorithm based on the Sporadic Task Frist(STF).It achieve the goal of improving the average response time of sporadic tasks by assigning higher priority to sporadic tasks and executing real-time sporadic tasks as early as possible.