Load Testing · Senior · Question 24 of 76
Server histograms have buckets 100, 250, 500, 1000 ms. Why may the reported p99 = 900 ms be imprecise?
- 1Buckets above 500 ms always round down to 500 ms
- 2Histograms can only report percentiles up to p95 at most
- 3The value is interpolated inside a wide bucket, not measured
Show the answer
Correct answer: The value is interpolated inside a wide bucket, not measured
Explanation
The true p99 lies somewhere between 500 and 1000 ms. Choose bucket edges near your SLO threshold so the answer to "are we under 300 ms?" is exact.