【摘要】 轨道交通实时以太网交换机作为新一代列车通信网络的重要组成部分,保障了列车状态信息与控制命令的交换和传输。实时以太网交换机基于嵌入式Linux系统构建,系统启动包括BootLoader启动、内核镜像加载、内核启动、用户空间初始化4个部分,其启动耗时直接影响着交换机甚至整个列车通信网络的性能。通过对嵌入式Linux启动过程与JFFS2,UBIFS等文件系统在嵌入式系统上挂载耗时的研究与分析,针对交换机启动过程提出相应的加速策略。采用内核裁剪、调整文件系统类型与优化系统启动参数等优化策略,使交换机的启动性能大幅提升。实验表明,交换机系统的启动时间从原有的26.69s减少至7.15s,启动时间减少了73.2%。更多还原

【Abstract】 As the important component for the next generation of train communication networks,railway real-time Ethernet switch ensures the data exchange and transmission for status and control information.The boot-up of the switch,based on the embedded Linux system,includes BootLoader starting,kernel image loading,Linux kernel boot and user space initialization.The boot-up time directly affects the performance of switch or even the entire train communication networks.The boot-up process of the embedded Linux system and the mounting cost for various file systems,e.g.JFFS2 and UBIFS,were studied.The strategy for each process in boot-up was proposed to reduce the time cost.By reducing kernel,replacing file system and optimizing boot-up parameters,the performance of system boot-up was significantly improved.Experiments show that the boot-up time decreases from 26.69 seconds to 7.15 seconds,which is reduced by 73.2%.更多还原