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From: march@m.cs.uiuc.edu
Newsgroups: comp.arch
Subject: Paging page tables
Message-ID: <3300142@m.cs.uiuc.edu>
Date: 27 Jun 90 18:55:00 GMT
Lines: 20
Nf-ID: #N:m.cs.uiuc.edu:3300142:000:949
Nf-From: m.cs.uiuc.edu!march    Jun 27 13:55:00 1990


While reading Hennessey and Patterson (p. 437), they mention the fact
that page tables entries are often paged themselves (with the operative
word being often).  Now to me, paging you're means of address translation 
makes no sense.  As they continue to point out, the cost of this is 
appreciable because one has to swap the PTEs back in and then do the 
translation.  Given this, just how "often" is this used?  I suppose
given a translation-lookaside buffer, the hugh cost of swapping page
table entries back in could be offset by some translations being very
fast (via the TLB).

Anyone ... ?

-Steve

===============================================================================
Steve March                            (H) (217)328-5176/328-5230  (W) 333-7408
Domain: march@cs.uiuc.edu             Path: {uunet|convex|pur-ee}!uiucdcs!march
"Time and space are modes by which we think and not conditions in which
 we live."  - Albert Einstein