2021-10-28: canary registry storage latencies increase

Current Status

After enabling the metadata DB for registry in gprd-cny, we saw an SLI drop for route manifests reads and an increase of storage latencies for registry.

Timeline

Recent Events (available internally only):

All times UTC.

2021-10-28

  • 08:09 - MR for enabling registry DB in gprd-cny merged
  • 08:30 - Deployment finished, storage latencies start to go up
  • 08:54 - alert for read manifist reads paging EOC
  • 09:12 - revert MR merged
  • 09:14 - @hphilipps declares incident in Slack.
  • 09:50 - staging QA tests fail (unrelated flaky test), QA pipeline needs to be restarted
  • 10:15 - deployment of the revert to cny starts
  • 10:20 - storage latencies are going down to normal levels

Corrective Actions

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Incident Review
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Customer Impact

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Incident Response Analysis

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Post Incident Analysis

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Lessons Learned

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Guidelines

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Edited by Henri Philipps