谁能详细介绍一下VMS

virtual memory
虚拟存储器

the main storage in a virtual memory system.
虚拟内存中的主要存储系统。

memory system
存储系统

That field of the total address(virtual or physical) that defines the page containing the desired address in apaged memory system.
在分页存储器系统中，虚或实总地址中定义包含所需地址的页面的字段（中的内容）。

(computer science) a use of the hard disk to simulate additional random-access memory; the addressable storage space available to the user of a computer system in which virtual addresses are mapped into real addresses.
模拟额外的只读存储器的硬盘；计算机系统的可用存储地址空间，空间内的虚拟地址可以转化为真实地址。