---
- name: Installing redis
  apt:
    update_cache: yes
    state: present
    name: redis-server

# Enable Memory Overcommit /etc/sysctl.conf vm.overcommit_memory = 1
# View with sysctl -a |grep overcommit
- name: Enable Memory Overcommit /etc/sysctl.conf vm.overcommit_memory = 1
  sysctl:
    name: vm.overcommit_memory
    value: 1
    reload: yes
    state: present
  notify: restart redis # Only runs if file changed!

# Disable Swapping /etc/sysctl.conf vm.swappiness = 0
- name: Setting /etc/sysctl.conf vm.swappiness = 0
  sysctl:
    name: vm.swappiness
    value: 0
    reload: yes
    state: present
  notify: restart redis # Only runs if file changed!

# Disable THP (Transparent Huge Pages)
# View with cat /sys/kernel/mm/transparent_hugepage/enabled
# View with cat /sys/kernel/mm/transparent_hugepage/defrag
# Copy systemd unit /etc/systemd/system/disable-thp.service
- name: Disable Transperent Huge Pages using Systemd unit /etc/systemd/system/disable-thp.service
  template:
    src: "files/disable-thp.service"
    dest: "/etc/systemd/system/disable-thp.service"
    owner: root
    group: root
    mode: 0644 # -rw-r--r--
  notify:
    - disable thp
    - restart redis # Only runs if file changed!