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From: Bob Friesenhahn <bfriesen@simple.dallas.tx.us>
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To: Frank Warmerdam <warmerdam@pobox.com>
Subject: Re: [Tiff] Memory leak (TIFFOpen, TIFFReadTile)?
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On Mon, 17 Nov 2008, Frank Warmerdam wrote:
>
> I am interested in advice on whether to change TIFFOpen() to *not* use
> memory mapped IO by default.  Presumably the application would need to
> pass "M" in the open options if they wanted memory mapping when possible.

I am not sure there is a need to change the current default.  A 
read-only memory mapping (as libtiff uses) is much less trouble for a 
system than read-write memory mappings.  The reason for this is that 
when the system needs to reclaim memory, read-only pages can be simply 
expired whereas read-write memory mappings need to take care to 
persist any dirty pages before the page is expired.

Installed system memory is growing by leaps and bounds so it is 
becoming common that systems have far more RAM installed than the 
largest TIFF file the system will ever read.

Bob
======================================
Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/

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