From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <c8685c768718ef790629270acb1927c5@plan9.bell-labs.com>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] Virtual memory & paging
From: "rob pike" <rob@plan9.bell-labs.com>
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Date: Sun,  3 Feb 2002 16:21:08 -0500
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I don't know that anyone else makes this distinction, but to me
virtual memory is a technique an operating system can use to manage
user memory, while paging is a technique for coping with a shortfall
in physical memory.  VM manages memory by using page faults to fill in
the user address space; paging is just swapping a page at a time.  The
relationship between these notions is primarily that both permit the
process to execute when it is not entirely resident.

By these definitions, it is possible (easy even) to build a system
with virtual memory but no paging.  Even I can do it.

-rob