[Gdal-dev] Will increasing the RAM on a server increase the speed of gdalwarp?

[Frank Warmerdam]

John Mitchell wrote:
> Hi,
> 
> Will increasing the RAM on a server increase the speed of gdalwarp?
> 
> If I have a server that currently has 4 gigs of RAM and I increase the 
> RAM to say 75 gigs will I notice a difference in the speed of processing 
> a 75 gig image via gdalwarp?

John,

What commandline options are you using with gdalwarp?  By default
gdalwarp won't take much advantage of your 4GB of existing RAM.

You might want to try setting the -wm flag. For example "-wm 500" will
operate on 500MB chunks at a time which is better than the default.
Increasing the io block cache size may also help.  This can be done
on the command like:

gdalwarp --config GDAL_CACHEMAX 500 -wm 500 ...

This uses 500MB of RAM for read/write caching, and 500MB of RAM for
working buffers during the warp.  Beyond that I'm doubtful more
memory will make a substantial difference.

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