Connection Pool Saturation Under Load
warningLinkerd proxy connection pools can become saturated during traffic spikes, causing increased latency and waiters. Pool size limits and too-many-waiters conditions indicate backend service capacity issues.
Monitor linkerd_rt_client_pool_count_too_many_waiters and linkerd_rt_client_pool_count_waited for non-zero values. Check linkerd_rt_client_pool_size approaching limits. Watch for increased linkerd_rt_client_pool_waiters during traffic peaks.
Increase backend service replica count to handle load. Tune connection pool settings in service profiles if custom limits are set. Investigate backend service response times using linkerd_rt_client_request_time_ms_quantile to identify slow endpoints. Consider implementing request queuing or load shedding.