Example 2

hosts.yml

centos:
  hosts:
    provisioner:
      ansible_connection: local
    centos1:
      ansible_host: '192.168.77.22'
ubuntu:
  hosts:
    ubuntu1:
      ansible_host: '192.168.77.23'

playbook.yml

- hosts: all
  gather_facts: false
  tasks:
    - name: 1st sleep
      command: sleep 5
      when: inventory_hostname == 'provisioner'
    - name: 2nd sleep
      command: sleep 5
      when: inventory_hostname == 'centos1'
    - name: 3rd sleep
      command: sleep 5
      when: inventory_hostname == 'ubuntu1'
    - name: 4th sleep
      command: sleep 5
      when: inventory_hostname == 'provisioner'
    - name: 5th sleep
      command: sleep 5
      when: inventory_hostname == 'centos1'

Tip

Ansible's parallelism, by default, is limited to the task level and a predefined number of forks.

Execute the following command

time ansible-playbook playbook.yml

Do you expect to see improved results compared to Example 1?

No, because we will still have to wait for the task to finish on the assigned host during each step.