Loïc Faugeron has continued his series about speeding up Symfony applications and getting the best overall performance you can. In this new post he gets into more detail about tuning a Nginx web server (with PHP-FPM) and the web server's own caching features.

HTTP frameworks, such as Symfony, allow us to build applications that have the potential to achieve Super Speed.

We've already seen a first way to do so (by turning it into a HTTP server), another way would be to put a reverse proxy in front of it. In this article we'll take a Symfony application and demonstrate how to do so using nginx.

He starts by helping you get Nginx and PHP-FPM all set up and running on a Unix-based system (installed via apt-get). He provides a simple configuration including the user to run as and a virtual host for the application. There's a few command line checks to ensure it's working correctly and a bit of benchmarking as a baseline for the performance testing later. He then gets to the caching functionality and gives some of the basics on how it works inside of Nginx itself. He includes a basic caching configuration (caching to files) and adding this to the already created virtual host. Finally he includes sample Symfony code to send the "Cache-Control" header with every request and runs the benchmarks again (resulting in about 140x faster than without the cache).

On the Tillate Blog today there's a new post from Leo looking at how you can give clients back the control on when your cache refreshes.

We worked hard on the right caching strategy over months now. But there are still caches that do not get invalidated right or are cached too long and we still get complaints from our users. So we decided to integrate a feature that allows certain users to invalidate the cache on the server side. The first idea was to add a link to every page that will append a GET-parameter to the site and then avoid the cache.

He used the apache_request_header function to get the current request's headers and noticed that they included a cache-control header. By changing up this on the client-side, it allows the site visitor to "force" an update to the information if your application pays attention to it.