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

The fastest way to check existence of a local file is stream_resolve_include_path():

if (false !== stream_resolve_include_path($s3url)) { 
  //do stuff 
}

Performance results stream_resolve_include_path() vs file_exists():

Test name       Repeats         Result          Performance     
stream_resolve  10000           0.051710 sec    +0.00%
file_exists     10000           0.067452 sec    -30.44%

In test used absolute paths. Test source is here. PHP version:

PHP 5.4.23-1~dotdeb.1 (cli) (built: Dec 13 2013 21:53:21)
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