Problem A: Your setup went from 1 server to multiple servers. theme_imagecache()/theme_imagefield_image() is taking a lot longer due to the files directory being a NFS mount (etc...).
Solution: Caching so PHP doesn't hit the disk to get the image info.
Problem B: Waiting for imagecache to generate all the images after you press node save.
Solution: Generate imagecache images right after the image is uploaded.
- Imageinfo Cache adds a caching layer right before theme_imagecache()/theme_imagefield_image() is called; thus future requests do not access the disk when requesting image_get_info() which calls getimagesize() and filesize(). This saves disk hits, and if your files directory is shared, you might see some big improvements in performance as a result.
- Imageinfo Cache will grab the image right after it's been uploaded from the CCK widget and will generate all imagecache presets. It will also run the file through the 2 theme functions mentioned above so the cache is primed. This happens in the background, not taking any resources from the
This module was created to solve a unique issue with a multi webhead system. Works best when not using the database for caching; recommend using something like memcache.
Part of this has been fixed in D7 #908282: Remove unnecessary I/O from theme_image() so holding off on a port right now; but am very open to patches for it.
Also see http://drupal.org/project/rules_image_styles