file_exists() is too slow in PHP. Can anyone suggest a faster alternative?

Question

When displaying images on our website, we check if the file exists with a call to file_exists(). We fall back to a dummy image if the file was missing.

Howe

Answer 1

Create a hashing routine for sharding the files into multiple sub-directories.

filename.jpg -> 012345 -> /01/23/45.jpg

Also, you could use mod_rewrite to return your placeholder image for requests to your image directory that 404.