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Mail Archives: djgpp/1999/04/15/06:41:42

Date: Thu, 15 Apr 1999 13:38:01 +0300 (IDT)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
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To: yjtseng <yjtseng AT micron DOT com>
cc: djgpp AT delorie DOT com
Subject: RE: cwsdpr0.exe 4/13/99
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On Tue, 13 Apr 1999, yjtseng wrote:

> What will happen if virtual memory is disabled (as is in cwsdpr0.exe),
> paging is enabled (as shown in CR0 I read), and pages need to be swapped
> out?

As explained here by others, the paging bit has nothing to do  with
swapping pages out.  The paging bit simply indicates whether the 
page tables and page directrories are used by the CPU to map logical 
addresses to physical addresses.

As for your question, pages need to be swapped out when there's not 
enough physical RAM to satisfy some memory request.  When VM is disabled, 
the memory request simply fails (e.g., you get NULL from `malloc'), and
no swapping ever happens.

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