"...because PHP isn't thread safe and developers write shitty code assuming it is." http://www.iis-aid.com/articles/my_word/difference_between_php_thread_safe_

"...because PHP isn't thread safe and developers write shitty code assuming it is." http://www.iis-aid.com/articles/my_word/difference_between_php_thread_safe_and_non_thread_safe_binaries http://www.iis-aid.com/articles/my_word/difference_between_p... "Another option is to configure IIS to use PHP in FastCGI mode which allows PHP processes to be recycled rather than killed off after each PHP request and also allows you to run several PHP processes at once, making PHP much much faster with the added bonus that as it is using the CGI interface there is little or no incompatibility issues with PHP extensions. This is still the fastest way to serve PHP, and is the way the IIS Aid PHP Installer is configured to install PHP on your IIS Environment."