PostgreSQLMetricredis.connections.rejected
Number of connections rejected due to maxclientsSummary
Counts connection attempts rejected because Redis reached its maxclients limit. Any non-zero value indicates capacity issues — the server cannot accept new clients because all connection slots are occupied. This triggers the connection rejection cascade insight: rejected connections cause application errors, which trigger retries, further increasing rejection rates. Immediate remediation requires either increasing maxclients or identifying and terminating leaked/idle connections.
Related Insights (2)
When async endpoints make synchronous Redis calls, they hold connections longer than necessary while blocking the event loop, causing artificial connection pool exhaustion even when Redis server capacity is available.
When Redis reaches maximum client connections (redis.connections.rejected increasing), new connection attempts fail silently while existing connections continue working normally, creating intermittent failures that are difficult to diagnose from application metrics alone.