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2022-08-13: sidekiq import error rate and apdex exceeding SLO

Incident Roles

The DRI for this incident is the incident issue assignee, see roles and responsibilities.

Roles when the incident was declared:

Current Status

This turned out to not be a practical problem. The alerts were a false alarm, triggered as a lingering effect of a previous delay in processing import jobs.

For context:

A few hours ago, the queue of import jobs accumulated a large backlog, and that backlog has now resolved. The alerts that are still triggering look back over the last 6 hours, and that previous regression was making the alerts more sensitive than intended, such that even a single failed job was triggering the alert.

Summary for CMOC notice / Exec summary:

  1. Customer Impact: None. Project imports had been delayed by a few hours previously, but that backlog has been resolved.
  2. Service Impact: ServiceSidekiq, specifically import jobs
  3. Impact Duration: N/A
  4. Root cause: RootCauseFalseAlarm due to the alert having become temporarily overly sensitive after a previous incident that resolved less than 6 hours ago eroded its noise suppression.

Timeline

Recent Events (available internally only):

All times UTC.

2022-08-13

  • 16:59 - @msmiley declares incident in Slack.

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Corrective Actions

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Incident Review
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Customer Impact

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What were the root causes?

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Incident Response Analysis

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  3. How was the root cause diagnosed?
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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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What went well?

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Guidelines

Resources

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Edited by Matt Smiley