*BSD News Article 27043


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From: cchen@cs.sunysb.edu (temp acct to clean dir)
Newsgroups: comp.os.386bsd.development
Subject: NetBSD vm question
Date: 7 Feb 1994 08:25:35 GMT
Organization: State University of New York, Stony Brook
Lines: 20
Distribution: world
Message-ID: <2j4ttv$996@newsserv.cs.sunysb.edu>
NNTP-Posting-Host: sbsynchem.cs.sunysb.edu

Please forgive the naivety if this is really a stupid
question.  

Does NetBSD really use a swap area at all?  I was trying
to find out how it handles memory mapped files.
In memory mapping, a pager is setup to retrieve pages 
from the file at page fault time,  Later, the page may
be swapped out if necessary.  Now, if the page is
faulted again, from my current understanding of the code,
the same pager will be called.  Wouldn't it try
to get the page from the same file, and not from the
swap area where it is supposed to?

My question is, how does the pager know to behave differently
under the two situations?

Thanks.

-Chyouhwa