git.stella-ops.org/tests/load

Load Tests

This directory contains k6 load test suites for StellaOps performance testing.

Prerequisites

• k6 installed
• Target environment accessible
• (Optional) Grafana k6 Cloud for distributed testing

Test Suites

TTFS Load Test (ttfs-load-test.js)

Tests the Time to First Signal endpoint under various load conditions.

Scenarios:

• Sustained: 50 RPS for 5 minutes (normal operation)
• Spike: Ramp from 50 to 200 RPS, hold, ramp down (CI burst simulation)
• Soak: 25 RPS for 15 minutes (stability test)

Thresholds (per Advisory §12.4):

• Cache-hit P95 ≤ 250ms
• Cold-path P95 ≤ 500ms
• Error rate < 0.1%

Run locally:

k6 run tests/load/ttfs-load-test.js

Run against staging:

k6 run --env BASE_URL=https://staging.stellaops.local \
       --env AUTH_TOKEN=$STAGING_TOKEN \
       tests/load/ttfs-load-test.js

Run with custom run IDs:

k6 run --env BASE_URL=http://localhost:5000 \
       --env RUN_IDS='["run-1","run-2","run-3"]' \
       tests/load/ttfs-load-test.js

Router Rate Limiting Load Test (router-rate-limiting-load-test.js)

Exercises Router rate limiting behavior under load (instance/environment limits, mixed routes) and validates 429 + Retry-After.

Scenarios:

• below_limit (A): sustained load below expected limits
• above_limit (B): ramp above expected limits (expect some 429)
• route_mix (C): mixed-path traffic to exercise route matching/overrides
• activation_gate (F): low traffic then spike (activation gate exercise)

Run locally:

mkdir results
k6 run --env BASE_URL=http://localhost:5000 \
       --env PATH=/api/test \
       tests/load/router-rate-limiting-load-test.js

Run with multiple paths (route mix):

mkdir results
k6 run --env BASE_URL=http://localhost:5000 \
       --env PATHS_JSON='[\"/api/a\",\"/api/b\",\"/api/c\"]' \
       tests/load/router-rate-limiting-load-test.js

CI Integration

Load tests can be integrated into CI pipelines. See .gitea/workflows/load-test.yml for an example.

load-test-ttfs:
  runs-on: ubuntu-latest
  needs: [deploy-staging]
  steps:
    - uses: grafana/k6-action@v0.3.1
      with:
        filename: tests/load/ttfs-load-test.js
      env:
        BASE_URL: ${{ secrets.STAGING_URL }}
        AUTH_TOKEN: ${{ secrets.STAGING_TOKEN }}

Results

Test results are written to results/ttfs-load-test-latest.json and timestamped files.

Use Grafana Cloud or local Prometheus + Grafana to visualize results:

k6 run --out json=results/metrics.json tests/load/ttfs-load-test.js

Writing New Load Tests

1. Create a new .js file in this directory
2. Define scenarios, thresholds, and the default function
3. Use custom metrics for domain-specific measurements
4. Add handleSummary for result export
5. Update this README

Environment Variables

Variable	Description	Default
BASE_URL	Target API base URL	http://localhost:5000
RUN_IDS	JSON array of run IDs to test	["run-load-1",...,"run-load-5"]
TENANT_ID	Tenant ID header value	load-test-tenant
AUTH_TOKEN	Bearer token for authentication	(none)
METHOD	HTTP method for router rate limiting test	GET
PATH	Single path for router rate limiting test	/api/test
PATHS_JSON	JSON array of paths for route mix	(none)
RESULTS_DIR	Output directory for JSON artifacts	results