Starting from version 2.4 apache offers 3 MPM we can choose, it’s depend in what you needs.
- prefork MPM uses multiple child processes without threading. Each process handles one connection at a time without creating separate threads for each.
- worker MPM uses several threads per child processes, where each thread handles one connection at a time.
- event MPM It is similar to the worker MPM in that it also creates multiple threads per child process but with an advantage: it causes KeepAlive or idle connections (while they remain in that state) to be handled by a single thread, thus freeing up memory that can be allocated to other threads. This MPM is not suitable for non-thread-safe modules like mod_php, to use event MPM, PHP-FPM must be used instead.
check the MPM used by your Apache:
# httpd -V
AH00558: httpd: Could not reliably determine the server's fully qualified domain name, using 202.74.43.187. Set the 'ServerName' directive globally to suppress this message
Server version: Apache/2.4.6 (CentOS)
Server built: Nov 19 2015 21:43:13
Server's Module Magic Number: 20120211:24
Server loaded: APR 1.4.8, APR-UTIL 1.5.2
Compiled using: APR 1.4.8, APR-UTIL 1.5.2
Architecture: 64-bit
Server MPM: prefork
threaded: no
forked: yes (variable process count)
Server compiled with....
-D APR_HAS_SENDFILE
-D APR_HAS_MMAP
-D APR_HAVE_IPV6 (IPv4-mapped addresses enabled)
-D APR_USE_SYSVSEM_SERIALIZE
-D APR_USE_PTHREAD_SERIALIZE
-D SINGLE_LISTEN_UNSERIALIZED_ACCEPT
-D APR_HAS_OTHER_CHILD
-D AP_HAVE_RELIABLE_PIPED_LOGS
-D DYNAMIC_MODULE_LIMIT=256
-D HTTPD_ROOT="/etc/httpd"
-D SUEXEC_BIN="/usr/sbin/suexec"
-D DEFAULT_PIDLOG="/run/httpd/httpd.pid"
-D DEFAULT_SCOREBOARD="logs/apache_runtime_status"
-D DEFAULT_ERRORLOG="logs/error_log"
-D AP_TYPES_CONFIG_FILE="conf/mime.types"
-D SERVER_CONFIG_FILE="conf/httpd.conf"
To change this, edit /etc/httpd/conf.modules.d/00-mpm.conf
and uncomment the line that loads mpm_event_module
LoadModule mpm_event_module modules/mod_mpm_event.so
install php-fpm, fcgi,mod_fcgid
# yum -y install php-fpm mod_fcgid fcgi
change php handler in order to use php-fpm in /etc/httpd/conf.d/php.conf
<FilesMatch \.php$>
# SetHandler application/x-httpd-php
SetHandler "proxy:fcgi://127.0.0.1:9000"
</FilesMatch>
restart/start all services
# systemctl start php-fpm.service
# systemctl enable php-fpm.service
# systemctl restart httpd.service
recheck the MPM used by your Apache:
# httpd -V
AH00558: httpd: Could not reliably determine the server's fully qualified domain name, using 202.74.43.187. Set the 'ServerName' directive globally to suppress this message
Server version: Apache/2.4.6 (CentOS)
Server built: Nov 19 2015 21:43:13
Server's Module Magic Number: 20120211:24
Server loaded: APR 1.4.8, APR-UTIL 1.5.2
Compiled using: APR 1.4.8, APR-UTIL 1.5.2
Architecture: 64-bit
Server MPM: event
threaded: yes (fixed thread count)
forked: yes (variable process count)
Server compiled with....
-D APR_HAS_SENDFILE
-D APR_HAS_MMAP
-D APR_HAVE_IPV6 (IPv4-mapped addresses enabled)
-D APR_USE_SYSVSEM_SERIALIZE
-D APR_USE_PTHREAD_SERIALIZE
-D SINGLE_LISTEN_UNSERIALIZED_ACCEPT
-D APR_HAS_OTHER_CHILD
-D AP_HAVE_RELIABLE_PIPED_LOGS
-D DYNAMIC_MODULE_LIMIT=256
-D HTTPD_ROOT="/etc/httpd"
-D SUEXEC_BIN="/usr/sbin/suexec"
-D DEFAULT_PIDLOG="/run/httpd/httpd.pid"
-D DEFAULT_SCOREBOARD="logs/apache_runtime_status"
-D DEFAULT_ERRORLOG="logs/error_log"
-D AP_TYPES_CONFIG_FILE="conf/mime.types"
-D SERVER_CONFIG_FILE="conf/httpd.conf"
create phpinfo if php handler using fpm/fastCGI now
$ echo '<?php phpinfo(); ?>' > /var/www/html/info.php
have fun 🙂