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##### SUMMARY
We a playbook that is using `ansible_ssh_common_args` which proxy the command through a jumphost using ssh keys. The play we are running uses `command` to copy files between hosts, the play also has `async: 600` on it. 

The issue is that under the `/home/ansible/.ansible_async` folder leaves files behind that have the output of the single async file copy and _never_ cleans up the files. Over time this leads to the system running out of inodes as for every file that was copied a file is created, saved, and never deleted after the play. 

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
`async` task flag

##### ANSIBLE VERSION
```paste below
ansible-playbook 2.9.7
  config file = /etc/ansible/ansible.cfg
  configured module search path = ['/var/lib/awx/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python3.6/site-packages/ansible
  executable location = /usr/bin/ansible-playbook
  python version = 3.6.8 (default, Nov 21 2019, 19:31:34) [GCC 8.3.1 20190507 (Red Hat 8.3.1-4)]
Using /etc/ansible/ansible.cfg as config file
host_list declined parsing /tmp/awx_124793_637oraq9/tmpu7_ol0_8 as it did not pass its verify_file() method
Parsed /tmp/awx_124793_637oraq9/tmpu7_ol0_8 inventory source with script plugin
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below
Defaults
```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. target OS versions, network device firmware, etc. -->
Jumphost: CentOS 7
Target OS: AIX 7.1

##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->

<!--- Paste example playbooks or commands between quotes below -->
Playbook
```yaml
- name: copy files
  hosts: all
  gather_facts: yes
  vars:
    source_system_paths:
      - "/test" 
    source_host: ""
  tasks:
    - name: Sync Folders cmd
      become: true
      become_user: ansible
      command: time sudo rsync -av -e "/usr/bin/ssh -o StrictHostKeyChecking=no -i /home/ansible/.ssh/id_rsa" ansible@"{{ source_host }}":"{{ item }}" "{{ item }}"
      with_items:
        - "{{ source_system_paths }}"
      loop_control:
        extended: yes
      async: 600
      poll: 5
```
Run ansible with following flags:
```
ansible_ssh_common_args: '-o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null -o ProxyCommand="ssh -W %h:%p {{ jh_ssh_user }}@{{ jh_ip }} -i $JH_SSH_PRIVATE_KEY -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null"'
```
In the home directory of the anisble user on the target host you will find `~/.ansible_async` where files will be created for each file that was copied. 

##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->
The folder or its contents from the run, `~/.ansible_async` is deleted completely or the files that were created by the playbook are deleted. 

##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->

FIles are never deleted and over time the system will run out of space, inodes, etc... as there are files left behind from _all_ previous runs. 

'''
        Runs the task with the loop items specified and collates the result
        into an array named 'results' which is inserted into the final result
        along with the item for which the loop ran.
        '''
        results = []
        
        
        
        task_vars = self._job_vars
        loop_var = 'item'
        index_var = None
        label = None
        loop_pause = 0
        extended = False
        templar = Templar(loader=self._loader, variables=self._job_vars)
        
        if self._task.loop_control:
            loop_var = templar.template(self._task.loop_control.loop_var)
            index_var = templar.template(self._task.loop_control.index_var)
            loop_pause = templar.template(self._task.loop_control.pause)
            extended = templar.template(self._task.loop_control.extended)
            
            label = self._task.loop_control.label
        
        if label is None:
            label = '{{' + loop_var + '}}'