From owner-freebsd-hackers  Tue Dec 25 10:20:16 2001
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Date: Tue, 25 Dec 2001 10:04:36 -0800 (PST)
From: Julian Elischer <julian@elischer.org>
To: Barak Enat <barak_enat@yahoo.com>
Cc: freebsd-hackers@freebsd.org
Subject: Re: Virtual memory and paging questions
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On Tue, 25 Dec 2001, Barak Enat wrote:

> Hi all,
> 
> Note: Please reply to this mail as well because I'm not subscribed to
> this mailing list.
> 
> I have two questions regarding FreeBSD virtual memory and
> paging/swapping system:
> 
> 1. When a page fault occurs does the entire system stalls, or only the
> process that requested the page suspends till the asynchronous
> completion of the page read?

Only the process requiring the page

> 
> 2. If I create a memory disk (md) and later use it for swapping
> (sounds awkward - but still this is what I need...), when a page fault
> occurs does a physical memcopy happen from the md page to the main
> memory page, or is there a trick in the vm page mapping to actually
> use the same physical page from the md? If such a trick exist, where
> is it in the code (because I want to turn it off - I need the simple
> memcopy behaviour.)

I think you are in luck..



> 
> Thanks in adavnce, Barak
> 
> 


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