validate_hypervisor.yml

---
- name: Validate hypervisor
  hosts: hypervisor
  gather_facts: yes
  any_errors_fatal: true
  vars:
      memory_buffer: 1.2
  tasks:
      - name: calculate needed memory
        include_tasks: tasks/calc_needed_memory.yml
        with_dict: "{{ provision.topology.nodes }}"
        loop_control:
            loop_var: node

      - debug:
            msg: "Current free memory is {{ ansible_memory_mb.nocache.free }}MB. The required memory for the topology is {{ nodes_memory }}MB and it is more than free memory, but it is under the buffer of 20%."
        when:
            - nodes_memory|int > ansible_memory_mb.nocache.free|int
            - nodes_memory|int <= ansible_memory_mb.nocache.free|int * memory_buffer|float

      - fail:
            msg: "Not enough memory on Hypervisor. Current free memory is {{ ansible_memory_mb.nocache.free }}MB, required is {{ nodes_memory }}MB. Use `--host-memory-overcommit True` if you want to overcommit memory usage"
        when:
            - nodes_memory|int > ansible_memory_mb.nocache.free|int * memory_buffer|float
            - not provision.host.memory.overcommit|default('False')