2021-07-13: Increase in errors across multiple GitLab.com services

Current Status

From 15:28 - 15:42 UTC, GitLab.com experienced a brief degradation across multiple services, primarily web and api. There followed a backlog of user CI workloads which were processed in another 30 minutes.

In the meantime, we were also having some difficulty seeing metrics details in our monitoring dashboards which are now also working

Summary for CMOC notice / Exec summary:

1. Customer Impact: ServiceAPI ServiceWeb ServiceGit ServiceCI Runners
2. Customer Impact Duration:

• Web, API and Git: 15:28 UTC - 15:42 UTC (14 minutes)
• CI Runners:

1. Current state: See Incident::<state> label
2. Root cause: TBD

Timeline

View recent production deployment and configuration events / gcp events (internal only)

All times UTC.

2021-07-13

• 15:33 - @nnelson noticed a plunging git apdex and elevation in haproxy 500 errors.
• 15:34 - @nnelson declares incident in Slack.
• 15:34 - apdex degradation across multiple services.
• 15:35 - monitoring services begin to show symptoms of strain, the thanos-frontend may have crashed and been restarted.
• 15:38 - service apdex disruptions appear to be returning to normal, however queue processing for user CI workloads seems to be backlogged.
• 16:00 - sidekiq queue length seems to have returned to normal, and job processing appears to be keeping up with user requests.

Corrective Actions

Corrective actions should be put here as soon as an incident is mitigated, ensure that all corrective actions mentioned in the notes below are included.

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Click to expand or collapse the Incident Review section.

Incident Review

Summary

1. Service(s) affected:
2. Team attribution:
3. Time to detection:
4. Minutes downtime or degradation:

Metrics

Customer Impact

1. Who was impacted by this incident? (i.e. external customers, internal customers)
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2. What was the customer experience during the incident? (i.e. preventing them from doing X, incorrect display of Y, ...)
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3. How many customers were affected?
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4. If a precise customer impact number is unknown, what is the estimated impact (number and ratio of failed requests, amount of traffic drop, ...)?
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What were the root causes?

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Incident Response Analysis

1. How was the incident detected?
   1. ...
2. How could detection time be improved?
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3. How was the root cause diagnosed?
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4. How could time to diagnosis be improved?
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5. How did we reach the point where we knew how to mitigate the impact?
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6. How could time to mitigation be improved?
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7. What went well?
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Post Incident Analysis

1. Did we have other events in the past with the same root cause?
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2. Do we have existing backlog items that would've prevented or greatly reduced the impact of this incident?
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3. Was this incident triggered by a change (deployment of code or change to infrastructure)? If yes, link the issue.
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Lessons Learned

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Guidelines

• Blameless RCA Guideline

Resources

1. If the Situation Zoom room was utilised, recording will be automatically uploaded to Incident room Google Drive folder (private)