Only create swapfile if there isnt one already

roles/common/tasks/main.yml

@@ -70,26 +70,55 @@
 - name: Add update line to update script
   shell: echo apt-get update && apt-get upgrade -y && apt-get clean && apt-get autoclean && apt-get autoremove -y && apt-get update >> /etc/cron.daily/update.sh
 
-- name: Allocate swap file
-  shell: fallocate -l 4G /swapfile
+- name: test for swap partition
+  shell: swapon -s | grep -E "^/"
+  register: swapfile
+  ignore_errors: yes
 
-- name: Secure swapfile
-  shell: chmod 600 /swapfile
+- name: create swapfile
+  when: swapfile|failed
+  shell: fallocate -l 4G /swapfile 
 
-- name: Make swap file
+- name: set swapfile permissions
+  when: swapfile|failed
+  file: path=/swapfile
+        owner=root
+        group=root
+        mode=0600
+
+- name: prepare swapfile
+  when: swapfile|failed
   shell: mkswap /swapfile
 
-- name: Enable swap file
+- name: enable swap
+  when: swapfile|failed
   shell: swapon /swapfile
 
-- name: Fix swappiness
-  shell: echo "sysctl vm.swappiness=10" >> /etc/sysctl.conf
+- name: add swapfile
+  when: swapfile|failed
+  lineinfile: dest=/etc/fstab
+              regexp="^/swapfile"
+              state=present
+              line="/swapfile       none    swap    sw      0       0"
 
-- name: Set current swappiness
-  shell: sysctl vm.swappiness=10
+- name: set swappiness (temporarily)
+  when: swapfile|failed
+  shell: echo 10 | tee /proc/sys/vm/swappiness
 
-- name: Fix cache pressure
-  shell: echo "sysctl vm.vfs_cache_pressure=50" >> /etc/sysctl.conf
+- name: set swappiness (permanent)
+  when: swapfile|failed
+  lineinfile: dest=/etc/sysctl.conf
+              regexp="^vm.swappiness"
+              state=present
+              line="vm.swappiness = 10"
 
-- name: Set current cache pressure
-  shell: sysctl vm.vfs_cache_pressure=50
+- name: set cache pressure (temporarily)
+  when: swapfile|failed
+  shell: echo 50 | tee /proc/sys/vm/vfs_cache_pressure
+
+- name: set cache pressure (permanent)
+  when: swapfile|failed
+  lineinfile: dest=/etc/sysctl.conf
+              regexp="^vm.vfs_cache_pressure"
+              state=present
+              line="vm.swappiness = 50"