---
- name: test for swap partition
  shell: swapon -s | grep -E "^/mnt/swapfile"
  register: swapfile
  ignore_errors: yes

- name: disable any other swap
  shell: swapoff -a
  when: swapfile|failed

- name: swap - remove current swaps from fstab
  lineinfile:
    dest: /etc/fstab
    regexp: '^\/[\S]+\s+none\s+swap '
    state: absent
  when: swapfile|failed

- name: create swapfile
  when: swapfile|failed
  shell: fallocate -l 4G /mnt/swapfile
  ignore_errors: yes

- name: set swapfile permissions
  when: swapfile|failed
  file: path=/mnt/swapfile
        owner=root
        group=root
        mode=0600

- name: prepare swapfile
  when: swapfile|failed
  shell: mkswap /mnt/swapfile
  ignore_errors: yes

- name: enable swap
  when: swapfile|failed
  shell: swapon /mnt/swapfile
  ignore_errors: yes

- name: add swapfile
  when: swapfile|failed
  lineinfile: dest=/etc/fstab
              regexp="^/mnt/swapfile"
              state=present
              line="/mnt/swapfile       none    swap    sw      0       0"

- name: set swappiness (temporarily)
  when: swapfile|failed
  shell: echo 10 > /proc/sys/vm/swappiness
  ignore_errors: yes

- name: set swappiness (permanent)
  when: swapfile|failed
  lineinfile: dest=/etc/sysctl.conf
              regexp="^vm.swappiness"
              state=present
              line="vm.swappiness = 10"

- name: set cache pressure (temporarily)
  when: swapfile|failed
  shell: echo 50 > /proc/sys/vm/vfs_cache_pressure
  ignore_errors: yes

- name: set cache pressure (permanent)
  when: swapfile|failed
  lineinfile: dest=/etc/sysctl.conf
              regexp="^vm.vfs_cache_pressure"
              state=present
              line="vm.vfs_cache_pressure = 50"