2022-08-09: GCS slowness in zone us-east1-c affecting apdex of Imagescaler and Pages services

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): @twk3, @splattael (Shadow)
  • Engineer on-call (EOC): @msmiley

Current Status

In 1 of the GCP zones (us-east1-c), interactions with GCS object storage are experiencing elevated response times. This is affecting the apdex of dependent services, including:

  • ImageScaler: Resizing avatar images of the user when rendering the web UI may be slower than usual.
  • Pages: Hosted content may be intermittently slower to fetch.
  • Registry: No significant impact currently. Registry apdex remains well within SLO.

Currently the effect appears to be mild. The regression in zone us-east1-c may have started as early as 2022-08-01, but only for brief timespans. Starting on 2022-08-08 (yesterday), the performance difference between zones became longer-lived but still mild. Today's regression was also intermittent, at peak affecting 2% of requests to imagescaler. Those imagescaler requests are not blocking, so the end-user experience of the web UI should have remained functional.

We are working with GCP support to identify the cause of the regression.

Due to the mild nature of the disruption, currently leaving the incident severity level at severity4. We will adjust that as needed, particularly if Registry becomes impacted.

More information will be added as we investigate the issue. For customers believed to be affected by this incident, please subscribe to this issue or monitor our status page for further updates.

Summary for CMOC notice / Exec summary:

  1. Customer Impact: Requests to Pages domains may be intermittently slower than usual.
  2. Service Impact: ServicePages ServiceWeb
  3. Impact Duration: Intermittent, starting on 2022-08-08
  4. Root cause: RootCauseExternal-Dependency

Timeline

Recent Events (available internally only):

All times UTC.

2022-08-09

  • 17:31 - @msmiley declares incident in Slack.

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Edited by Matt Smiley