> Based on your description, I suspect that either Photoshop's memory usage
> may be somewhat more efficient than the GIMP, or possibly your Tile Cache
> Size is set too small. Either of those issues could result in extensive
> page thrashing of portions of the GIMP and your image to and from disk.
> my system, the tile cache size is set to 1280MB. How much physical RAM do
> you have, and what is your Tile Cache Size set to?
Also, what other memory hog applications do you have running at the same
time? For example, you didn't have the same image already open in Photoshop
while you were testing the GIMP on it did you? If so, that could have
easily pushed the required memory beyond your installed RAM size, forcing
extensive page swapping to/from disk.
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