operating system - What's the difference between "virtual memory" and "swap space"? -

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can 1 please make me clear difference between virtual memory , swap space?

and why 32-bit machine maximum virtual memory access 4 gb only?

there's excellent explantation of virtual memory on over superuser.

simply put, virtual memory combination of ram , disk space running processes can use.

swap space portion of virtual memory on hard disk, used when ram full.

as why 32bit cpu limited 4gb virtual memory, it's addressed here:

by definition, 32-bit processor uses 32 bits refer location of each byte of memory. 2^32 = 4.2 billion, means memory address that's 32 bits long can refer 4.2 billion unique locations (i.e. 4 gb).


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