prometheus.service

- Prometheus runs at localhost:9099
  - Configuration is stored at ~/.config/prometheus/prometheus.yaml
  - Data is stored at ~/.local/share/prometheus/data/
  - Data retention is set to 180 days
- node_exporter runs at localhost:9109
- Both run as systemd user service units which are stored at
  ~/.config/systemd/user
  - ref: https://wiki.archlinux.org/index.php/Systemd/User



Signed-off-by: Bhavin Gandhi <bhavin7392@gmail.com>