Chapter 19: Test Cases — MaxSignaling, Stability, Latency Jitter
Test Case Types
| Type | What It Measures | Example TC |
|---|---|---|
| MaxSignaling | Max rate at target CPU% (capacity) | PcgUpf_MaxSignaling_Dataplane_Medium_CeeF_LPC1 |
| Latency Jitter | PFCP response time distribution | PcgGwu_LatencyJitter_PfcpEndpoint_Medium_CeeB_MbbA |
| Stability | Sustained load over hours (degradation) | PcgUpf_MBB_Stability_Bm1F_3h |
MaxSignaling: How It Works
// Test sends a fixed rate to SUT and measures CPU:
// - If CPU is within target range (e.g., 63±5%) → PASS
// - If CPU exceeds range → FAIL
// - Calculates "rate @80% vCPU" by linear extrapolation
// Parameters:
// Rate: 14500 (sessions/sec sent to SUT)
// CPU usage required: exactly 63±5% (data-plane)
// Resendings: < 100 (acceptable retransmissions)
// Failed: < 1 (acceptable failures)Latency Jitter: How It Works
Sends PFCP requests at a fixed rate and measures response time percentiles (p50, p95, p99). Used to detect latency regressions.
Stability: How It Works
Runs sustained traffic for 3-12 hours. Checks for memory leaks, CPU drift, counter anomalies. Good for detecting gradual degradation.
Which TCs for This Feature
- Latency: PcgGwu_LatencyJitter (fixed rate, measure response time)
- Capacity: PcgUpf_MaxSignaling_Dataplane (measure rate@80%)
- System impact: Stability TCs on Genoa/Turin hardware (3-6 hour runs)
- Robustness: Worker node restart, pod restart (latency under failure)