避免饥饿的CAN总线高优先级反转算法  

High Priority Inversion Algorithm for CAN Bus to Avoid Starvation

作　　者：赵国承 张凤登[1] ZHAO Guo-cheng;ZHANG Feng-deng(School of Optical-Electrical and Computer Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China)

机构地区：[1]上海理工大学光电信息与计算机工程学院,上海200093

出　　处：《软件导刊》2022年第3期119-123,共5页Software Guide

基　　金：上海市自然科学基金项目(15ZR1429300)。

摘　　要：为解决CAN总线中高优先级报文发送请求总是阻止低优先级报文的发送请求,即CAN总线基于固定优先级的策略可能导致低优先级报文饥饿问题,提出一种避免饥饿的CAN总线高优先级反转算法。采用非抢占式单调速率算法来分配CAN总线报文优先级,通过仿真分析低优先级组报文在不同CAN总线利用率下的平均响应时间以及到达率。实验结果表明,在使用避免饥饿的CAN总线高优先级反转算法后,随着总线利用率递增,其报文平均响应时间分别降低了6.9%、9.5%、10.7%、21.9%、43.29%,而且在总线利用率超过100%时,低优先级组报文的到达率仍为1,表明该算法能够有效避免CAN总线中低优先级报文的饥饿问题。In order to solve the problem that the sending request of high priority message always blocks the sending request of low priority message in CAN bus,that is,the strategy based on fixed priority in CAN bus may lead to the starvation problem of low priority message,a CAN bus high priority inversion algorithm to avoid starvation is proposed.The algorithm uses a non-preemptive rate monotone algorithm to allocate the priority of CAN bus messages.The average response time and arrival rate of low priority group messages under different can bus utilization are analyzed by simulation.The results of the running simulation showed that after using the CAN bus high priority inversion algorithm to avoid starvation,as the bus utilization increases,the average response time of the message is reduced by6.9%,9.5%,10.7%,21.9%and 43.29%respectively,and when the bus utilization exceeds 100%,the arrival rate of low-priority group messages can still be 1.Therefore,the proposed algorithm can effectively avoid the starvation problem caused by low priority messages on CAN bus,which proves the effectiveness of the algorithm.

关 键 词：优先级反转 CAN总线 优先级队列 响应时间 

分 类 号：TP301.6[自动化与计算机技术—计算机系统结构]