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From: gnu@l5.uucp (John Gilmore)
Newsgroups: net.arch
Subject: Re: Why Virtual Memory
Message-ID: <240@l5.uucp>
Date: Wed, 30-Oct-85 17:49:28 EST
Article-I.D.: l5.240
Posted: Wed Oct 30 17:49:28 1985
Date-Received: Sun, 3-Nov-85 07:51:39 EST
References: <480@seismo.CSS.GOV>, <384@unc.unc.UUCP> <6086@utzoo.UUCP>
Organization: Nebula Consultants in San Francisco
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Summary: Even with cheap RAM, an MMU is cheaper than more RAM

One thing you vmunix users might try is running "top" (show top N processes
and assorted stats about the system) to answer this question.

Almost all the processes have about a third of their address space paged in.
Is an MMU cheaper than three times as much memory?  Sure, especially if
you are using it for memory protection anyway.
--
What is the sound of one disk paging?