XHProf

This module allows you to profile your Drupal application using the XHProf profiler, Tideways and uprofiler (PHP 5 only)

Use community documentation to install/enable required PHP extension

XHProf is a hierarchical profiler for PHP. It reports function-level call counts and inclusive and exclusive metrics such as wall (elapsed) time, CPU time and memory usage. A function's profile can be broken down by callers or callees. The raw data collection component is implemented in C as a PHP Zend extension called xhprof. XHProf has a simple HTML based user interface (written in PHP). The browser based UI for viewing profiler results makes it easy to view results or to share results with peers. A callgraph image view is also supported.

It also provides a native Drupal UI (as opposed to facebook's original php front end) to view the profiling data. Having this in Drupal provides several advantages:

• Simpler setup
• No need to setup extra vhosts
• Limit access via roles and permissions
• Use alternative storage backends such as MongoDb

D8+ version also supports:

• Profilers: XHProf, Tideways and uprofiler (PHP 5 only).
• Append --xh-link and Drush 8 will save a profile to the same directory that this module uses. Browse Drush 8 profile data with this module.