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Degraded Performance — Feature Flags in PROD2

Resolved incidentMinor1 affected service

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  1. Investigating

    We are currently investigating this issue.

  2. Monitoring

    A fix has been implemented and we are monitoring the results.

  3. Resolved

    This incident has been resolved.

  4. Resolved

    ### Summary

    On April 24, 2026, a large non-batched bulk DELETE operation on the prod-2 primary database triggered lock contention, causing Feature Flag API latency and hung queries across multiple customer SDKs.

    ### Impact

    1. Slow SDK auth/init — SDKs took longer than expected to complete evaluations

    2. Elevated latency across many FF APIs

    3. Limited to Feature Flag module, prod-2

    4. No Data loss

    ### Root Cause

    A background cleanup job executed a non-batched, single-transaction delete causing lock contention and API latency spikes

    Mitigation

    Immediately terminated the offending queries.

    ### Next Steps / Action Items

    To prevent such issues from happening again. we are working on

    1. Enhanced alerting and observability on long running queries.

    2. Permanently replace large single-transaction delete pattern with smaller batched deletes