2024-09-09: Multiple metrics show less jitter on many VMs
Customer Impact
None known so far. Currently this is just an investigation of an unexpected change in some utilization metrics.
Current Status
Multiple metrics for many distinct VMs all abruptly showed less jitter in their measurements, starting at 2024-09-09 16:27 UTC.
Initially this was discovered while looking at some resource utilization metrics, but it turns out that the same reduction of jitter affected other kinds of metrics too (e.g. event counters). So this looks like an outcome of a change somewhere in the metrics ingestion pipeline -- an observability change, not a resource usage change.
The jitter that we now lack may in fact have been a form of measurement aggregation error. The individual exporters maintain a local scrape count, and it shows a noticeably more consistent rate after the jitter vanished.
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.
📚 References and helpful links
Recent Events (available internally only):
- Feature Flag Log - Chatops to toggle Feature Flags Documentation
- Infrastructure Configurations
- GCP Events (e.g. host failure)
Deployment Guidance
- Deployments Log | Gitlab.com Latest Updates
- Reach out to Release Managers for S1/S2 incidents to discuss Rollbacks, Hot Patching or speeding up deployments. | Rollback Runbook | Hot Patch Runbook
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