You might need to override MySQL's default setting for wait_timeout in Cloud Platform or Site Factory. For example, your logs might display the following error message:

Fatal error: Uncaught PDOException: SQLSTATE[HY000]: General error: 2006 MySQL server has gone away in [..snip..]/core/lib/Drupal/Core/Database/[..snip..]

You cannot override this setting on the MySQL server configuration as such settings are centrally managed. However, you can override it on a per session basis. For example, for every PHP process that bootstraps Drupal. For more information, visit How to override the default MySQL wait_timeout setting.