Improve the real or perceived speed of the site, or monitor performance metrics.
Drupal's standard Field storage module loads makes 1 SQL query per field during entity load, which can be suboptimal with many fields.
This module allows post processing of render arrays just after them being retrieved from cache. It allows you to apply small per-user modifications
This module adds lazy load functionality to all image field. An optional text format provides the ability to lazy load images added to text areas.
The bad performance module purposely decreases the response time and increases the CPU load of any Drupal site it's installed on.
Advanced Varnish provides seamless integration between your Drupal site and Varnish Cache, a powerful reverse proxy that dramatically improves website performance and reduces server load.