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Circuit Breaker Trip Preventing OOM

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reliabilityUpdated Feb 6, 2026

Circuit breakers trip (CB_TrippedEvents increases) when CB_EstimatedSize approaches CB_ConfiguredSize, preventing out-of-memory errors but causing request failures. Multiple breaker types protect different memory pools.

How to detect:

Monitor CB_TrippedEvents for any circuit breaker type (request, fielddata, in-flight requests, etc.). Track CB_EstimatedSize approaching CB_ConfiguredSize thresholds. Correlate with Heap_Used increases and specific operation types causing breaker trips.

Recommended action:

Identify which circuit breaker is tripping most frequently. For request breaker: reduce query result sizes. For fielddata: limit fielddata usage or increase cache size. For in-flight: reduce concurrent requests. Consider increasing heap size or scaling cluster horizontally.