Client Output Buffer Limits Causing Disconnections
warningWhen Redis disconnects slow clients that can't keep up with output buffer, redis.clients.connected drops suddenly. This is often caused by clients with slow network connections or blocking on their end, especially for pub/sub subscribers or replicas.
Monitor redis.clients.connected for sudden drops. Correlate with redis.net.output rate increases indicating buffering. Check redis.memory.mem_clients_normal for memory consumed by client output buffers. Sudden drops in redis.clients.connected_slaves may indicate replica output buffer issues.
Review client-output-buffer-limit settings for normal, replica, and pubsub clients. Increase limits if legitimate slow clients need accommodation. Investigate why clients can't keep up - network issues, client-side processing lag, or too many pub/sub channels. For replicas, ensure network bandwidth is adequate for replication load. Use CLIENT LIST command to identify clients with large output buffers.