00:00Instead of letting a process point directly into physical memory, we add virtual memory as a layer in between.
00:08Each process gets its own virtual address space, and that space always looks like one big continuous block, starting at
00:14address 0 and growing upward.
00:16Let's go back to the machine with six physical units.
00:19Process A starts and asks for two units.
00:21In its virtual address space, it gets two continuous slots, virtual unit 1 and virtual unit 2.
00:27Behind the scenes, the operating system may create a mapping from virtual unit 1 to physical unit 2, and from
00:36virtual unit 2 to physical unit 3.
00:38From process A's point of view, that memory looks completely continuous because it only ever sees virtual unit 1 and
00:462.
00:47It doesn't know or care that underneath the data lives in physical unit 2 and 3.
00:54And the same thing happens...
