halkyon / experiment-phpfpm

Using containers to test different PHP worker models, e.g. mod_php vs fpm

Experimentation with PHP-FPM

Why?

SilverStripe traditionally uses mod_php to serve PHP requests, so it was interesting to see if PHP-FPM could be used instead to see if memory usage could be reduced.

Usage

First of all, clone this repo into a location in your filesystem somewhere.

In addition to the usual composer and php installed, please also ensure docker and docker-compose are installed.

Now in the repository:

composer install

Now you can choose which configuration to start below.

Once the containers have come up, you can access the site on http://localhost:8200

Apache with PHP-FPM

This approach has the advantage in that all .htaccess files are used. The downside is the overhead of reading these configuration files on each request, whether it is PHP or a static file.

docker-compose -f docker-compose-fpm-apache.yml up --build

This uses the httpd Docker image. Configuration for apache is located in apache-fpm-template/httpd.conf.

nginx with PHP-FPM

This approach has the advantage in that nginx is very efficient in serving static assets. The downside is .htaccess files are no longer used, so you'll need to write equivalent nginx configuration.

docker-compose -f docker-compose-fpm-nginx.yml up --build

This uses the nginx Docker image. Configuration for apache is located in nginx-fpm-template/httpd.conf.

nginx with Apache mod_php

This is the "traditional" way of running PHP, in which PHP support is bundled into Apache as a module. nginx is kept at the front to serve static assets, while offloading anything else to Apache. .htaccess files are read on each PHP request, which doesn't make it super efficient, combined with the fact that Apache must run in mpm_prefork to ensure thread safety for PHP instead of the more efficient mpm_event.

docker-compose -f docker-compose-modphp-nginx.yml up --build

This uses the php Docker image.

Currently broken: port on apache is wrong and returns URLs as http://localhost when forwarding docker container port to host on 8200.

Further investigation

http://linuxbsdos.com/2015/02/17/how-to-reduce-php-fpm-php5-fpm-ram-usage-by-about-50/

https://ma.ttias.be/a-better-way-to-run-php-fpm/

Testing

So far for each I have thrown siege at it to see how many transactions per second can be achieved.

Still to come: testing memory and CPU usage and comparing these.