Control trace sampling

Head sampling runs before export and reduces the telemetry received by Site Qwality. Configure a parent-based ratio sampler in your SDK, preserve the sampling decision across services and record the probability/threshold metadata the exporter supports. The backend cannot reconstruct individual requests that were never sent.

A Collector tail-sampling processor can retain errors and slow requests after seeing a trace. It needs enough memory, decision time and consistent routing for spans of the same trace. Tail sampling can bias latency/error estimates, so do not assume its retained subset represents all traffic without supported weights.

Processing pipelines can also sample or exclude received traces. RED derivation from received spans and trace retention are separate stages; inspect the estimated, partial and quality indicators. A graph built from incomplete spans may lack parents or dependencies. Sampling a trace away can leave an exemplar or RUM link without a retained target.

Use the Collector guide for transport and queues, then add the upstream tail sampling processor. Do not send production traffic through an unbounded queue. See ingest limits and trace reference.