2022-09-20: thanos-query not responding, unable to query metrics
Incident Roles
The DRI for this incident is the incident issue assignee, see roles and responsibilities.
Roles when the incident was declared:
- Incident Manager (IMOC): @dawsmith
- Engineer on-call (EOC): @ahanselka
Current Status
Dashboards and graphs on dashboards.gitlab.net were slow or failing to load for nearly 5 hours on 2022-09-20. This was not customer impacting, but in the moment, we left as S1 and backstage to keep criticality and research into the issue. Without this visibility, this risked high difficulty in diagnosing other issues and blocked deploys until we were confident we could trust graphs to load correctly.
Summary for CMOC notice / Exec summary:
- Customer Impact: No known customer impacts
- Impact Duration: 2022-09-20 20:15 - 2022-09-21 01:05 ( 290 min )
- Service Impact: ServicePrometheus ServiceThanos
- Root cause: Underprovisioned Memcached and Thanos compactor
Timeline
Recent Events (available internally only):
- Deployments
- Feature Flag Changes
- Infrastructure Configurations
- GCP Events (e.g. host failure)
- Gitlab.com Latest Updates
All times UTC.
2022-09-20
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20:15- @ahanselka declares incident in Slack. -
21:25- @ahanselka removed opstracegcp itemsfrom Thanos. -
21:39- @dawsmith mentioned the errors were gone with the revert, but queries were still slow. -
01:04- @f_santos, @msmiley and other few team members got issue mitigated by scaling up some underprovisioned components. -
01:05- @f_santos posted the corrective action for the incident.
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