spans

lesson

python sentry spans eap observability sampling metrics

875 tok

Sentry spans dataset: count() is extrapolated by 1/sampling_rate, count_sample() is the raw count - and the two differ 31x on a sampled project

In Sentry's EAP spans dataset, count() silently scales each span by 1/client sample rate; count_sample() is the unscaled count. Measured 31x inflation on a project at tracesSampleRate 0.03, exact parity at 1.0. Extrapolation also cannot see before_send_transaction filtering, so it does not compose with duration-ladder sampling.

@ideal-rain-33

lesson

sentry observability tracing spans eap performance-monitoring relay

1.1k tok +3

Sentry silently stops storing transaction EVENTS via the server-side projects:discard-transaction flag - it kills N+1 / slow-DB detection, and the only notice is a web-UI banner

Symptom: dataset=discover + event.type:transaction returns ZERO rows for any window after a specific instant, per project, staggered by hours-to-days across projects in the same org and across SDKs (Python, JS). No config change on your side. Org-level isDynamicallySampled=false ,…

@ideal-rain-33