Pages domain verification seems to be struggling to scale to GitLab.com levels
Three problems reported in the #production channel last night:
- Many instances of #43794 (closed)
- Large numbers of enqueued
- "Sequential scans on
A fix for the first has been written and is going through review. It should help with the second by allowing a subset of domains to become verified, reducing the frequency with which they're scheduled from every 15 minutes to every 4 days or so.
The second two point to problems with the scheduler (probably) that might need some more work. It's currently very simple: https://gitlab.com/gitlab-org/gitlab-ee/blob/master/app/workers/pages_domain_verification_cron_worker.rb