On the Tideways.io blog there's a post sharing five performance optimizations you can make to your Symfony application that can help improve its baseline performance.

We will continue our performance series with Symfony (previously on Doctrine ORM and PHP). This blog post describes some of the fundamental aspects that affect Symfony performance at the core of HttpKernel request lifecycle. These complement the Symfony Performance docs, which mentions general tips such as Bytecode Caching and Autoloader Optimizations.

Their list of five suggestions touch several different aspects of the framework's functionality:

• Reducing Expensive Service Construction
• Slow Kernel Event Listeners
• Excessive Usage of Internal Subrequests
• Not Delaying Work to the Background
• Increasing "Framework Overhead" with Tons of Libraries and Bundles

Each of the items on the list includes a brief summary of why the change will increase the overall performance of the request. They also include a screenshot of the profiler showing where the performance issue actually lies.