Subject: Re: 'growable' mmap regions
To: Jaromir Dolecek <jdolecek@NetBSD.org>
From: Jason Thorpe <thorpej@wasabisystems.com>
List: tech-kern
Date: 08/27/2004 19:51:21
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On Aug 27, 2004, at 3:59 PM, Jaromir Dolecek wrote:

> I'm not really convinced this is very useful when using virtual memory
> management - such scheme doesn't preserve VA space (since the space 
> must
> be reserved for the stack grow anyway), and physical pages are
> allocated on-demand, so bigger memory piece doesn't waste more 
> physical RAM
> than the small one (with overcommit, at least).

Actually, I think it would be kind of nice to generalize the handling 
of this in UVM, rather than handling it per-platform in the fault code.

Seems like it would be simple enough to mark a single vm_map_entry in 
this way, though you'd need some additional information (i.e. the 
current "depth").

         -- Jason R. Thorpe <thorpej@wasabisystems.com>


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