Cache Monitor

This module is currently in a very early state. Use at your own risk!

Cache monitor measures and stores cache performance data for each Drupal request. It provides an admin report where site builders and developers can analyze which cache bins consume the most time.

Features

Tracks cache operations (get, set, getMultiple, etc.) for all bins during every request.

Stores results in the database for later review, not just during a single request.

Provides an admin interface at /admin/reports/cache-metrics with:

An overview list of recent requests.

A detail view showing all bins, operations, calls, items, and timing.

A total cache time summary per request.

Helps developers identify performance bottlenecks caused by cache usage.

Useful for monitoring regressions or comparing performance when switching cache backends (e.g. APCu vs Redis).

Post-Installation

After enabling the module, no extra configuration is required.
Visit Reports → Cache Monitor Reports in the admin UI to view the data.

The module works automatically: each request is measured, results are stored, and you can browse them in the provided report. There are no new content types, configuration forms, or text formats.

Additional Requirements

No dependencies beyond Drupal core.

Requires permission “Administer GRF cache reports” to access the admin UI.

Creates two database tables to store request and metric data.

Similar projects

Webprofiler: Profiles cache calls per request but does not persist them.

This module differs by storing cache metrics historically, allowing analysis across multiple requests.