Maintenance change: Document trigram index rebuild.

In vain of https://gitlab.com/gitlab-com/infrastructure/issues/4418 this is ~S4 maintenance change. It is not expected to cause noticeable impact on GitLab.com.

Applying the change is expected to take a long time as we're rebuilding an index, pause for 3 hours and continue. This is to ensure that the database does not get overwhelmed by the change.

Steps to be taken:

  1. Review script
  2. Execute script on staging and document the time it takes
  3. Review & approve change
  4. Execute change

Roles:

  • EMOC: tbd
  • CT: tbd

Change scheduled for: tbd

Edited by Andreas Brandl