CentOS with Apache and PHP-FPM (revisited)
Published on 2018-05-30 | Last modified on 2018-06-01
Almost two years I wrote a post about using Apache
with PHP-FPM on CentOS. Some things have changed (for the better) and also I
somehow understand things better now! This post is about configuring Apache
with PHP-FPM on CentOS 7. The whole point of this is to increase the
performance of running PHP scripts. Even with PHP 5.4, the default on CentOS,
you'll see a substantial performance improvement compared to mod_php.
We will:
- Switch Apache to use MPM Event;
- Switch PHP-FPM to use the Unix socket;
- Make existing Apache "mod_php" configuration snippets work with PHP-FPM without modification.
Installation
$ sudo yum -y install httpd php-fpm
Make sure you don't have mod_php installed, i.e.:
$ sudo yum -y remove php
Configuration
Apache
We steal the configuration
file from
Fedora where since a few releases the PHP installation defaults to PHP-FPM. We
install that in /etc/httpd/conf.d/php.conf. The big advantage here is that
you don't need to modify any other Apache configuration files to make use of
PHP-FPM!
Furthermore, we switch to
MPM Event for performance
reasons. Modify /etc/httpd/conf.modules.d/00-mpm.conf and disable the
mpm_prefork_module and enable the mpm_event_module:
#LoadModule mpm_prefork_module modules/mod_mpm_prefork.so
LoadModule mpm_event_module modules/mod_mpm_event.so
Don't forget to restart Apache:
$ sudo systemctl restart httpd
PHP
By default on CentOS PHP-FPM will listen on a TCP port, we want to modify this
to use a Unix socket for performance reasons. Make sure you specified/modfied
at least these options in /etc/php-fpm.d/www.conf:
listen = /run/php-fpm/www.sock
listen.group = apache
listen.mode = 0660
The socket permissions will look like this, enough for Apache to talk to the socket:
$ ls -l /run/php-fpm/www.sock
srw-rw----. 1 root apache 0 May 23 09:16 /run/php-fpm/www.sock
Don't forget to restart PHP-FPM:
$ sudo systemctl restart php-fpm
This should be all to run your PHP scripts a lot faster with minimal configuration changes and be in line with the (default) configuration of PHP on Fedora and on CentOS 8 when it is finally released!
Update (2018-06-01): do not forget to install the OPcache extension to further improve performance:
$ sudo yum -y install php-opcache
$ sudo systemctl restart php-fpm