2020-11-13: component shared_runner_queues of ci-runners service has an apdex-scope outside of SLO
Summary
Shared runners on GitLab.com degraded in picking up new jobs as CPU spike on the runner managers. Investigation int the CPU saturation is ongoing, but has already started to recover.
Timeline
All times UTC.
2020-11-13
- 14:03 - We notice alerts about couple of CI runner managers are down (5 and 7)
- 14:12 - We're informed about a planned upgrade to the runners and these two runners are being investigated
- 14:28 - We restart one of the runner hosts (5) as we can't SSH into it
- 14:46 - EOC declares incident in Slack.
- 15:30 - Things appear to be recovering, investigation continuing.
Corrective Actions
Click to expand or collapse the Incident Review section.
Incident Review
Summary
- Service(s) affected:
- Team attribution:
- Minutes downtime or degradation:
Metrics
Customer Impact
- Who was impacted by this incident? (i.e. external customers, internal customers)
- What was the customer experience during the incident? (i.e. preventing them from doing X, incorrect display of Y, ...)
- How many customers were affected?
- If a precise customer impact number is unknown, what is the estimated potential impact?
Incident Response Analysis
- How was the event detected?
- How could detection time be improved?
- How did we reach the point where we knew how to mitigate the impact?
- How could time to mitigation be improved?
Post Incident Analysis
- How was the root cause diagnosed?
- How could time to diagnosis be improved?
- Do we have an existing backlog item that would've prevented or greatly reduced the impact of this incident?
- Was this incident triggered by a change (deployment of code or change to infrastructure. If yes, have you linked the issue which represents the change?)?
5 Whys
Lessons Learned
Guidelines
Edited by Dave Smith