Changelist files limit

Changelists or reviews with many files may take longer than usual to display in P4 Code Review. This is because of the time required to get the file listing from the P4 Server and then display the large number of files in the browser.

File listings with thousands of files, may cause P4 Code Review to run out of memory. Increasing the amount of memory for P4 Code Review can help, but the UI may work slower than usual or not at all depending on the amount of memory available in your browser.

With P4 Code Review 2025.1 and later, if the number of files in a changelist exceeds the max_changelist_files value, the Request Review button in the changelist page is disabled and you cannot request a review. This is to prevent P4 Code Review from running out of memory.

Toolip that reads "Maximum changelist file limit exceeded" when the Request Review button is disabled

You can adjust the file limit by changing the max_changelist_files value in the SWARM_ROOT/data/config.php file:

<?php
    'p4' => array(
         'max_changelist_files'  => 1000,
),

The default value of 1000 is sufficient for most P4 Code Review installations.

If you make a configuration change, P4 Code Review will not use it until the configuration cache has been reloaded, this forces P4 Code Review to use the new configuration. You must be an admin or super user to reload the P4 Code Review config cache. Navigate to the User id dropdown menu, select System Information, click the Cache Info tab, and click the Reload Configuration button.

Before changing the max_changelist_files value, consider the following effects of this change:

  • A large number of files in a change list may cause P4 Code Review UI issues. There is no real advantage to displaying more than 10,000 files at a time.
  • Smaller max_changelist_files values can interfere with changelists as the reduced file limit could prevent files from being displayed in P4 Code Review.