GitLab change history: Investigating delayed CI job pickup

GitLab reported a major GitLab.com CI/CD degradation affecting instance runners from 2026-09-02 11:54 UTC to 2026-09-02 12:43 UTC (49 min), delaying job pickup, pipelines and deployments. A manually initiated pg_repack maintenance operation caused CI database contention affecting runner communication; GitLab terminated the operation, runner metrics recovered, and the incident was resolved.