Override Unit systemd with OMkill less

postgresql/tasks/config.yml

@@ -1,4 +1,13 @@
 ---
+- name: Override PostgreSQL systemd unit
+  template:
+    src: postgresql.service.j2
+    dest: /etc/systemd/system/multi-user.target.wants/postgresql.service
+    force: yes
+  notify:
+    - reload systemd
+    - restart postgresql
+
 - name: Allow conf.d/*.conf files to be included in PostgreSQL configuration
   lineinfile:
     name: "/etc/postgresql/{{postgresql_version}}/main/postgresql.conf"

postgresql/templates/postgresql.service.j2

@@ -0,0 +1,19 @@
+# systemd service for managing all PostgreSQL clusters on the system. This
+# service is actually a systemd target, but we are using a service since
+# targets cannot be reloaded.
+
+[Unit]
+Description=PostgreSQL RDBMS
+
+[Service]
+OOMScoreAdjust=-1000
+Environment=PG_OOM_ADJUST_FILE=/proc/self/oom_score_adj
+Environment=PG_MASTER_OOM_SCORE_ADJ=-1000
+Environment=PG_CHILD_OOM_SCORE_ADJ=0
+Type=oneshot
+ExecStart=/bin/true
+ExecReload=/bin/true
+RemainAfterExit=on
+
+[Install]
+WantedBy=multi-user.target