理解内存页面调度的机制，在模拟实现FIFO、LRU、OPT算法的基础上，比较各种置换算法的效率和优劣，从而了解虚拟储存的实现过程-Understanding of the mechanisms of memory paging, on the basis of the simulation to achieve FIFO, LRU, OPT algorithm, compare the pros and cons of replacement algorithm efficiency and t