Some seriously good news here. It took several years of waiting, but, it finally happened. PHP-FPM project is officially BSD-licensed now, which means, that it has good chances to become a part of official PHP distribution.
PHP-FPM is “deciphered” as “PHP FastCGI Process Manager” and is a patch for php to greatly improve FastCGI SAPI usage in production. It adds a bunch of additional features to php’s fastcgi such as: easy php-process daemonization (with ability to specify uid/gid/chroot/log-file), safe php-processes restart (without losing requests), custom error-handling and accelerated file-upload support (requires additional support from web-server).
There’s not much documentation in english, currently, but, again, there is a good chance that it will be added really soon.