
MissCache serves a phpThumb thumbnail as a static file after the first request ("forge-on-miss"). The first hit generates and stores it; every later request is served by the web server with no PHP.
Cached static 400×300 thumbnail (served by Apache as a plain file):

Same image dynamically via img.php (regenerated each request):

cache URL: https://actionapps.org/img_upload/mC/pT/aadev/misc/missCache/demo/sample.jpg!w=400~-h=300~-zc=1.jpg