01
Performance Testing
Testing behavior under load: separating load, stress, soak and spike testing by the question each one asks, modeling realistic user behavior with think time and workload-mix ratios, choosing percentile latency and throughput metrics that reveal what an average hides, attributing a single result to the application, database and network layers, and a benchmarking discipline that avoids the traps of warm-up, noise and single-run readings.
- 01 Performance Testing Types Splitting behavior under load into four separate questions: load, stress, soak and spike testing reading the same metric in a different decision window, all four reaching four separate decisions on the same two structures, deriving a threshold from a budget split, and counting which type produces a false pass at which threshold range through a threshold scan.
- 02 Test Scenario Modeling The shape of the load, not its size: measuring at what share of the workload mix a defect becomes visible, a search-heavy unrealistic scenario producing a false pass at the same target rate, a closed-loop generator never reaching the target rate because of its virtual-user count and think time, and the same nominal rate giving three separate p95 values.
- 03 Metric Selection Drawing seven separate results from the same run: the mean and median passing the threshold while the tail percentiles fail, counting the minimum sample size a percentile needs to be readable through a subsample scan, and showing through a target-rate ladder that a latency figure cannot be read without the reached rate reported alongside it.
- 04 Bottleneck Analysis Tying a load-test result to a layer: measuring application, database and transfer duration separately within a request, attributing three modes that give the same client-side symptom to three separate layers, scanning the attribution rule against a share threshold, and showing with numbers a case where the time genuinely is spent in the right layer but the cause is a different decision.
- 05 Benchmarking Discipline The condition for a performance difference to count as meaningful: measuring the warm-up window with request blocks, counting a harness's own noise by running the same code as two arms, showing a round where a single-round reading reads a regression backwards, and balancing the false-fail–false-pass trade-off by scanning threshold and round count together.