RTEMS存储管理的研究与改进

Research and Improvement of RTEMS Memory Management

对嵌入式实时操作系统RTEMS的两种存储管理方法——分区和区域进行了分析和研究。分区管理是将内存划分为大小相等的缓存块,以队列的形成将空闲缓存块组织在一起,并以缓存块为单位动态地分配。区域管理以可变大小的内存段进行分配,用双向链表来管理空闲内存段,采用首次适应算法对内存进行分配。由于区域管理算法复杂,因此,本文提出带辅助位示图的位示图存储管理方案,使内存分配更加简单,同时也解决了空闲区合并问题,提高了RTEMS的可靠性和实时性。

This paper analyzes the two kinds of memory management - partition and region of RTEMS, a embedded real - time operating system. The partition management is a physically contiguous memory area divided into fixed - size buffers. The buffers are queued up and can be dynamically allocated. The region management is allocated into variable - sized segments by first - fit algorithm. The free segments are managed by a double link list. The algorithm of region managment is complex. So, the paper proposes a memory management method of bitmap with aid bitmap, which simplifies memory allocation, and handles the problem of free memory regions combina- tion and succeeds in promoting RTEMS reliability and real- time.