Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.3 4.3bsd-beta 6/6/85; site l5.uucp Path: utzoo!linus!philabs!cmcl2!harvard!seismo!lll-crg!well!ptsfa!l5!gnu 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 Lines: 8 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?