[FWTools] MrSID Reader performance?

[Frank Warmerdam]

Jason Birch wrote:
> Hi all,
> 
> I'm converting a few MrSID images out into TIFFs with a reduced
> resolution.  The first four went extremely fast, but the last one (which
> is the second-largest) is taking forever, and from the  page faulting
> like crazy.
> 
> Is there something about the dimensions of this image (100000x105000) or
> size (1,149,185,743 b) that would be causing this?  Another one that I
> just ran had a slightly larger size (by about 25 MB) but was a lot
> faster.
> 
> Is there an environment variable that I can tweak to give this more
> horsepower? :)

Jason,

I suspect you are seeing cache thrashing in which case you will want
to set the GDAL_CACHEMAX environment variable to a fair sized number (eg. 200).

set GDAL_CACHEMAX=200
gdal_translate ...

You can also do it directly in the command.

eg.
gdal_translate --config GDAL_CACHEMAX 200 ...

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