I've found that the source of some of my problems are the ImageServer running for the Scene7 imaging. My client dumped thousands of images on the system then deleted them before the processing could finish. Now the ImageServer is stuck trying to create thumbnails for images that no longer exist. It doesn't give up on the image when it can't find it, it just keeps retrying all the images. It has gotten to the point that now it is eating all of the resources on the server to the point that processing new images isn't happening.
How do I clear the cache of images it thinks it needs to process?
