[thredds] WMS servers side image cache

Hi, I'm playing around with using Thredds WMS using a tiling scheme similar to google maps and I was wondering if there was a way (or something that could be added in the future) to cache WMS maps from the thredds servlet? Since I'm using tiles, the requests are identical. I was thinking thredds would be able to hash (say md5) the request url and write the image to temporary folder. On the second request thredds would look in the cache based on the hash, and return the image if its there otherwise generate a new image. Thredds would likely need to wipe the cache on a restart in case the data changed.

Using IDL I wrote some code that downloaded all the tiles at all levels for a particular dataset, but it took about 12 hours to run and generated 400,000+ tiles for only one variable. If thredds cached images it would be a more "on demand" approach rather than trying to pre generate millions of tiles. In the tiled world, caching would say a lot of server side processing (especially for high resolution datasets) and speed up the user experience.

-Jay Alder