Performance hints please

[Frank Warmerdam]

Stephen Davies wrote:
> G'day Frank.
> 
> I reread the raster howto etc on overviews and do think they might help.
> 
> I have created some overviews of my TIFF images using gdaladdo but 
> cannot see how to tell mapserv to use them. Could you please give me a 
> pointer.

Stephen,

It should just use them automatically when they are appropriate for the
current map request.  You might want to verify that GDAL sees the overviews
by running "gdalinfo" on the dataset after gdaladdo, and ensuring there are
some overviews levels listed after the bands in the report.

There isn't any particularly easy way to ensure that mapserver is using
the overviews short of seeing better performance.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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