---
- hosts: undercloud
  vars:
    metadata:
      name: Check the number of OpenStack processes on undercloud
      description: >
        The default settings for OpenStack is to run one process (heat-engine,
        keystone, etc.) per CPU core. On a machine with a lot of cores this is
        both unnecessary and can consume a significant amount of RAM, leading
        to crashes due to OOMKiller.
      groups:
        - pre-deployment
    max_process_count: 8
  tasks:
  - name: Collect the number of running processes per OpenStack service
    command: 'docker exec {{ item.container }} pgrep -f -c {{ item.proc }}'
    become: true
    ignore_errors: yes
    register: "process_count"
    changed_when: False
    loop:
      - {container: "heat_engine",            proc: "heat-engine"}
      - {container: "ironic_inspector",       proc: "ironic-inspector"}
      - {container: "ironic_conductor",       proc: "ironic-conductor"}
      - {container: "nova_api",               proc: "nova_api"}
      - {container: "nova_scheduler",         proc: "nova-scheduler"}
      - {container: "nova_conductor",         proc: "nova-conductor"}
      - {container: "nova_compute",           proc: "nova-compute"}
      - {container: "glance_api",             proc: "glance-api"}
      - {container: "swift_proxy",            proc: "swift-proxy-server"}
      - {container: "swift_object_server",    proc: "swift-object-server"}
      - {container: "swift_container_server", proc: "swift-container-server"}
      - {container: "zaqar",                  proc: "zaqar"}
      - {container: "zaqar_websocket",        proc: "zaqar-server"}
      - {container: "mistral_api",            proc: "mistral-server"}
      - {container: "mistral_engine",         proc: "mistral-server"}
      - {container: "mistral_executor",       proc: "mistral-server"}

  - name: Create warning messages
    command: echo "There are {{ item.stdout }} {{ item.item }} processes running. Having more than {{ max_process_count }} risks running out of memory."
    register: process_warnings
    with_items: "{{ process_count.results }}"
    when: "item.stdout|int > max_process_count"

  - name: Output warning message
    warn: msg={{ warning_msg }}
    when: "warning_msg|length > 0"
    vars:
      warning_msg: "{{ process_warnings.results|selectattr('changed')|map(attribute='stdout')|join('\n') }}"