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Systemd setup ​

This guide assumes you have installed the EdgeComet binaries in /opt/edgecomet/bin and configuration files in /opt/edgecomet/configs.

Prerequisites ​

Before creating service files, set up the necessary user and directories.

1. Create service user ​

Create a dedicated system user for EdgeComet services.

bash
# Create system user and group
sudo useradd -r -s /bin/false -d /opt/edgecomet edgecomet

2. Create directories and set permissions ​

Ensure the service user can write to log and cache directories.

bash
# Create directories
sudo mkdir -p /var/log/edgecomet
sudo mkdir -p /var/cache/edgecomet

# Set ownership
sudo chown -R edgecomet:edgecomet /var/log/edgecomet
sudo chown -R edgecomet:edgecomet /var/cache/edgecomet
sudo chown -R edgecomet:edgecomet /opt/edgecomet

3. Install dependencies ​

For the Render Service, ensure a compatible browser is installed:

bash
# Ubuntu/Debian
sudo apt-get update && sudo apt-get install -y chromium-browser

Service files ​

Edge Gateway ​

Create /etc/systemd/system/edgecomet-edge-gateway.service:

ini
[Unit]
Description=EdgeComet Edge Gateway
After=network.target redis.service
Wants=redis.service

[Service]
Type=simple
User=edgecomet
Group=edgecomet
WorkingDirectory=/opt/edgecomet
ExecStart=/opt/edgecomet/bin/edge-gateway -c /opt/edgecomet/configs/edge-gateway.yaml
Restart=on-failure
RestartSec=5
# High file descriptor limit for handling concurrent connections
LimitNOFILE=65535
# Allow 45s for graceful shutdown (app timeout is 30s)
TimeoutStopSec=45

[Install]
WantedBy=multi-user.target

Render Service ​

Create /etc/systemd/system/edgecomet-render-service.service:

ini
[Unit]
Description=EdgeComet Render Service
After=network.target redis.service
Wants=redis.service

[Service]
Type=simple
User=edgecomet
Group=edgecomet
WorkingDirectory=/opt/edgecomet
ExecStart=/opt/edgecomet/bin/render-service -c /opt/edgecomet/configs/render-service.yaml
Restart=on-failure
RestartSec=5
LimitNOFILE=65535
# Memory limit for Chrome pool (adjust based on system RAM)
MemoryMax=8G
# Allow 45s for graceful shutdown (draining in-flight renders)
TimeoutStopSec=45

[Install]
WantedBy=multi-user.target

Cache Daemon (optional) ​

Create /etc/systemd/system/edgecomet-cache-daemon.service:

ini
[Unit]
Description=EdgeComet Cache Daemon
After=network.target redis.service edgecomet-edge-gateway.service

[Service]
Type=simple
User=edgecomet
Group=edgecomet
WorkingDirectory=/opt/edgecomet
ExecStart=/opt/edgecomet/bin/cache-daemon -c /opt/edgecomet/configs/cache-daemon.yaml
Restart=on-failure
RestartSec=10

[Install]
WantedBy=multi-user.target

Service ordering ​

Start services in this specific order to ensure proper registration and discovery:

  1. Redis: Must be running first for coordination.
  2. Render Service: Registers itself in Redis upon startup.
  3. Edge Gateway: Starts and discovers available Render Services from Redis.
  4. Cache Daemon: Connects to Edge Gateway.

Enable and start services ​

bash
# Reload systemd configuration
sudo systemctl daemon-reload

# Enable services to start on boot
sudo systemctl enable edgecomet-render-service
sudo systemctl enable edgecomet-edge-gateway
sudo systemctl enable edgecomet-cache-daemon

# Start services (respecting the order)
sudo systemctl start edgecomet-render-service
sudo systemctl start edgecomet-edge-gateway
sudo systemctl start edgecomet-cache-daemon

Managing services ​

bash
# Check status
sudo systemctl status edgecomet-edge-gateway
sudo systemctl status edgecomet-render-service

# View logs (follow in real-time)
sudo journalctl -u edgecomet-edge-gateway -f
sudo journalctl -u edgecomet-render-service -f

# Restart specific service
sudo systemctl restart edgecomet-edge-gateway

Resource limits ​

File descriptors ​

  • LimitNOFILE=65535 is set by default to handle high concurrency in the Edge Gateway and Chrome processes.

Memory limits ​

  • Render Service: Set MemoryMax to prevent the Chrome pool from exhausting system RAM.
  • Rule of thumb: Allocate 500MB-1GB per Chrome instance. For 10 instances, allow ~8-10GB.

CPU limits (optional) ​

  • Use CPUQuota to restrict CPU usage if services share a host.
  • Example: CPUQuota=400% allows the service to use up to 4 CPU cores.

Graceful shutdown ​

EdgeComet services handle SIGTERM to ensure zero-downtime deployments:

  • Edge Gateway: Stops accepting new connections and waits up to 30s for existing requests to complete.
  • Render Service: Deregisters from Redis, stops the heartbeat, and finishes in-flight renders before exiting.