Design On Memory Management In Embedded MINIX Operating System

Nowadays, the research and development of the embedded operating system has become a popular field of the information technology. Compared to ordinary desktop operating system, embedded operating system is restricted by cost, equipment size, battery technology and other factors. Because of the limit of memory capacity, the memory must be used efficiently. What is more, many embedded operating systems are so important that they should run safely. In order to avoid disasters, memory management must be very reliable.MINIX is a commonly used multi-task operating systems using modular structure with high reliability, flexibility and security. Abiding by the "Small is beautiful" principle, the core part of MINIX is very small so that it is very suitable for embedded systems and high reliability for the applications.The main work of this paper is to study the commonly used embedded operating system memory management, analyze some common technologies in this area, and point out the characteristics and conditions of applications. And then based on ARM microprocessor platform, we have designed the embedded MINIX 3 OS memory management strategy for MMU, and also we have designed another memory management strategy without MMU. In this paper we create a memory interface in MINIX 3 kernel, and design paging on MINIX 3 memory management for MMU.For without MMU design, we modify the MINIX 3 memory management strategy to improve the utilization of memory and decrease debris. Therefore, MINIX 3 memory management is more in line with the requirements of embedded systems.