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Date: Mon, 17 Nov 2008 12:20:31 -0500
From: Frank Warmerdam <warmerdam@pobox.com>
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Subject: Re: [Tiff] Memory leak (TIFFOpen, TIFFReadTile)?
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Craig Bruce wrote:
> I have found that memory-mapped I/O is completely FUBARed, even on Linux.
> Even if the kernel is ultimately going to release the memory, the system
> still thrashes like crazy.  It really shouldn't be the default mode
> for TIFFOpen().

Folks,

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.

If there is consensus that the change would be good we can apply it in
4.0 and 3.9 branches.

I personally mostly use libtiff through my own IO layer which does not
offer memory mapping so I have little recent experience with the benefits
or problems of memory mapped io.

Best regards,
-- 
---------------------------------------+--------------------------------------
I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam@pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | Geospatial Programmer for Rent

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