The documentation is a little sparse though the mailing list and irc are useful for help.
Also it would somewhat depend on your traffic profile. If you've got thousands of random reads (e.g. thumbnails with dozens per page, ssds might be better; specifically the Intel X-25).
Otherwise MogileFS with an array of fast drives would probably do the job. Mogile can also do load balancing based on drive I/O because each image is replicated across different files/machines.
EDIT: Make sure you've got browser caching set up correctly (though admittedly that's a tiny bit harder with Mogile)
If you can use a expiry time that's far in the future.
Also don't send a Last-Modified nor an ETag Header.
Only send Expires.
http://www.danga.com/mogilefs/
with an nginx or lighttpd frontend.
The documentation is a little sparse though the mailing list and irc are useful for help.
Also it would somewhat depend on your traffic profile. If you've got thousands of random reads (e.g. thumbnails with dozens per page, ssds might be better; specifically the Intel X-25).
Otherwise MogileFS with an array of fast drives would probably do the job. Mogile can also do load balancing based on drive I/O because each image is replicated across different files/machines.
EDIT: Make sure you've got browser caching set up correctly (though admittedly that's a tiny bit harder with Mogile)
If you can use a expiry time that's far in the future. Also don't send a Last-Modified nor an ETag Header. Only send Expires.