forgejo-runner-optimiser/test/docker/docker-compose.yaml

# Docker Compose test setup for cgroup grouping verification
# Run with: docker compose -f test/docker/docker-compose.yaml up
#
# NOTE: Docker Compose doesn't have a direct equivalent to K8s shareProcessNamespace.
# Options:
#   1. pid: "host" - sees ALL host processes (not container-specific)
#   2. pid: "service:<name>" - chains PID namespace to another service
#
# For proper testing, use Kubernetes or run containers manually with --pid=container:<id>

services:
  # Simulate a runner workload (this will be the "root" of the shared PID namespace)
  # Uses 'cat' reading from a fifo as a unique identifiable process
  runner:
    image: busybox:latest
    command:
      - /bin/sh
      - -c
      - |
        echo "Runner started (PID 1 in namespace)"
        mkfifo /tmp/runner_fifo
        # 'cat' will be our identifiable runner process (blocks on fifo)
        cat /tmp/runner_fifo &
        CAT_PID=$!
        # Generate CPU load with dd
        while true; do
          dd if=/dev/zero of=/dev/null bs=1M count=50 2>/dev/null
        done
    deploy:
      resources:
        limits:
          cpus: "0.5"
          memory: 256M
    # This container owns the PID namespace

  # Simulate a sidecar service - shares PID namespace with runner
  sidecar:
    image: busybox:latest
    command:
      - /bin/sh
      - -c
      - |
        echo "Sidecar started"
        # List processes to verify shared namespace
        ps aux
        while true; do
          sleep 10
        done
    deploy:
      resources:
        limits:
          cpus: "0.1"
          memory: 128M
    pid: "service:runner"  # Share PID namespace with runner
    depends_on:
      - runner

  # Resource collector - shares PID namespace with runner
  collector:
    build:
      context: ../..
      dockerfile: Dockerfile
      target: collector
    command:
      - --interval=3s
      - --top=5
      - --log-format=json
    environment:
      # Map unique process names to container names
      # 'cat' runs only in runner, 'sleep' runs only in sidecar
      CGROUP_PROCESS_MAP: '{"cat":"runner","sleep":"sidecar","resource-collec":"collector"}'
      CGROUP_LIMITS: '{"runner":{"cpu":"500m","memory":"256Mi"},"sidecar":{"cpu":"100m","memory":"128Mi"},"collector":{"cpu":"100m","memory":"64Mi"}}'
    deploy:
      resources:
        limits:
          cpus: "0.1"
          memory: 64M
    pid: "service:runner"  # Share PID namespace with runner
    depends_on:
      - runner
      - sidecar