The problem with checking which MPM Apache is running under is that this information is compiled into Apache's own binary, so finding it out is not as simple as it seems.
Two methods for finding out which MPM Apache is running under
Information
The Apache binary is usually located at /usr/sbin/apache2 or, depending on the distribution, at /usr/sbin/httpd.
If it is not found in either of these locations, check the service startup script at /etc/init.d/apache2 or /etc/init.d/httpd.
Once you know the location of the web service binary, you need to run it with the “-l” argument to list the compiled modules:
core.c
mod_log_config.c
mod_logio.c
prefork.c
http_core.c
mod_so.cThis example indicates that it is running under prefork, so if you want to make changes to the Apache configuration, you must make them in the Prefork MPM.
Another method you can use to view the MPM in use is to run the following commands:
# apache2 -V | grep MPMOr:
# httpd -V | grep MPM