GenServer.call latency measurement vs Telemetry instrumentation: selecting an accurate approach
GenServer.call latency measurement vs Telemetry instrumentation When a GenServer receives a high‑frequency synchronous request, the round‑trip time of GenServer.call/3 can become a performance bottleneck. Two documented ways to capture this latency are :timer.tc/1 (or :erlang.monotonic_time/0 ) and Telemetry events emitted by the BEAM runtime. Each technique