Load Profile Configuration
The Load Profile defines how virtual users are ramped up, sustained, and ramped down during a performance test. Robonito supports four built-in load types, each suited for a different testing scenario.
Load Types
Fixed Load
All virtual users start simultaneously and run for the full test duration at a constant rate.
Best for: Sustained load testing, validating that your system can handle a known steady-state traffic level.
Configuration:
| Field | Description |
|---|---|
| Virtual Users | Number of concurrent users (1–10,000) |
| Duration | How long to maintain the load (1–60 minutes) |
Ramp Up
Virtual users increase gradually from 0 to the target count over the test duration, simulating a growing user base.
Best for: Finding the breaking point of your system — identifying at what load level response times degrade or errors appear.
Configuration:
The Ramp Up profile is edited with the interactive Load Profile Editor. Drag the phase handles to reshape the ramp curve. The X-axis is time (minutes) and the Y-axis is concurrent virtual users.
| Field | Description |
|---|---|
| Virtual Users | Maximum concurrent users at peak |
| Duration | Total test duration (1–60 minutes) |
Spike Test
Virtual users surge suddenly to the maximum and then drop back, simulating flash-sale events or traffic spikes.
Best for: Testing resilience to sudden bursts of traffic — verifying that your system recovers quickly after an overload.
Configuration:
Use the Load Profile Editor to drag the spike shape. The default is a sharp peak at the midpoint of the test duration.
| Field | Description |
|---|---|
| Virtual Users | Peak concurrent users during the spike |
| Duration | Total test duration |
Peak Test
Multiple sustained peaks separated by lower-traffic valleys, simulating a business day with morning rush, lunch lull, and afternoon surge.
Best for: Testing how your system handles shifting demand — validating that it scales up and down without degradation.
Configuration:
Use the Load Profile Editor to drag the phase handles and create the multi-peak shape. Each phase can be independently positioned.
The Load Profile Editor
For non-Fixed load types, the Load Profile Editor provides an interactive SVG canvas to shape the load curve visually.
| Control | Description |
|---|---|
| Drag phase handles | Pull up/down or left/right to reshape the load curve |
| Snap to grid | Toggle to snap drag positions to grid intervals for precise values |
| Show grid | Toggle the background grid lines |
| Reset | Restore the default shape for the selected load type |
| Phase badges | Color-coded labels showing each phase type (Ramp Up, Hold, Ramp Down) |
Success Criteria
Define thresholds that automatically fail the performance test if exceeded:
| Criterion | Description |
|---|---|
| P90 Response Time | 90th percentile latency must be below this value (milliseconds) |
| P95 Response Time | 95th percentile latency threshold (milliseconds) |
| P99 Response Time | 99th percentile latency threshold (milliseconds) |
| Error Rate | Percentage of failed requests must not exceed this threshold |
The comparison operator for each criterion is configurable: <, ≤, >, ≥.
If any criterion is breached, the performance run is marked as Failed and the threshold violation is highlighted in the Performance Monitor →.
Running a Performance Test
- Navigate to Performance in the sidebar.
- Select the API test cases to include (searchable, grouped by suite).
- Choose a Load Type and configure the profile.
- Set any Success Criteria.
- Click Run.
Robonito dispatches the test and opens the Performance Monitor → for real-time observation.