Use Java 7 with custom ARGS.

playbooks/roles/jenkins_master/defaults/main.yml

@@ -7,6 +7,7 @@ jenkins_port: 8080
 jenkins_version: "1.630"
 jenkins_deb_url: "http://pkg.jenkins-ci.org/debian/binary/jenkins_{{ jenkins_version }}_all.deb"
 jenkins_deb: "jenkins_{{ jenkins_version }}_all.deb"
+jenkins_jvm_args: "-Djava.awt.headless=true -Xmx6144m"
 
 jenkins_plugins:
     - { name: "build-name-setter", version: "1.3" }

playbooks/roles/jenkins_master/meta/main.yml

 ---
 dependencies:
   - common
-  - oraclejdk
+  - role: oraclejdk
+    tags: java

playbooks/roles/jenkins_master/tasks/main.yml

@@ -9,8 +9,8 @@
 
 - name: install jenkins extra system packages
   apt:
-    pkg={{','.join(JENKINS_EXTRA_PKGS)}}
-    state=present update_cache=yes
+    pkg={{ item }} state=present update_cache=yes
+  with_items: JENKINS_EXTRA_PKGS
   tags:
   - jenkins
 
@@ -38,6 +38,18 @@
 - name: stop Jenkins
   service: name=jenkins state=stopped
 
+- name: set jvm args
+  lineinfile: >
+    backup=yes
+    dest=/etc/default/jenkins
+    regexp='^JAVA_ARGS'
+    line='JAVA_ARGS=\"{{ jenkins_jvm_args }}\"'
+  notify:
+    - restart Jenkins
+  tags:
+    - java
+    - jenkins
+
 # Move /var/lib/jenkins to Jenkins home (on the EBS)
 - name: move /var/lib/jenkins
   command: mv /var/lib/jenkins {{ jenkins_home }}