The correct answer is Live Metrics Stream.

Live Metrics Stream provides near real time telemetry and aggregated metrics such as request latency and failure counts by opening a live connection to your application. It displays updating charts and counters so you can observe performance and error trends as they occur and quickly respond to issues.

Smart Detection analyzes telemetry to surface anomalies and potential problems over time but it does not give a continuously updating live stream of request latencies and error counts.

Profiler captures detailed CPU and performance traces to help diagnose hotspots and long running operations but it is not intended to show live aggregated metrics for latency and failures.

Snapshot Debugger captures snapshots of exceptions and request state for debugging specific failures in production but it does not provide a near real time metrics stream of latency and error counts.

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