Issue
We're expecting to see performance regression issues for a specific transaction, but none are being generated even though we notice slower transaction durations.
Applies To
Customers relying on Endpoint Regression issues
Resolution
Sentry’s performance issue detector analyzes the 95th percentile transaction duration of the most common endpoints in your project. Only transactions that meet certain thresholds - specifically being among the most common endpoints and having at least 50 events per hour - are eligible for regression detection.
If a transaction falls below these thresholds, it’s considered low throughput, and regression issues will not be created. The regression detection process uses a two-stage pipeline: first, trend detection identifies potential regressions in real time based on a 200 ms minimum change, 15 % relative change, and 18+ data points, then, breakpoint confirmation runs about 12 hours later to verify significance using statistical tests over three days of data. You can review the implementation details in Sentry’s open-source code: EndpointRegressionDetector + detector_algorithm_factory and Breakpoint confirmation logic.
In short, if your transaction doesn’t meet the event volume or endpoint frequency criteria, it won’t trigger regression issues until sufficient data is available.