diff --git a/inventory/host_vars/db-datanommer02.phx2.fedoraproject.org b/inventory/host_vars/db-datanommer02.phx2.fedoraproject.org
index d72490bda4..57562e1369 100644
--- a/inventory/host_vars/db-datanommer02.phx2.fedoraproject.org
+++ b/inventory/host_vars/db-datanommer02.phx2.fedoraproject.org
@@ -25,3 +25,6 @@ mem_size: 16384
 num_cpus: 8
 tcp_ports: [ 5432, 443 ]
 fas_client_groups: sysadmin-dba,sysadmin-noc
+
+# kernel SHMMAX value
+kernel_shmmax: 68719476736
diff --git a/inventory/host_vars/db-qa01.qa.fedoraproject.org b/inventory/host_vars/db-qa01.qa.fedoraproject.org
index a943195408..732b2d69ee 100644
--- a/inventory/host_vars/db-qa01.qa.fedoraproject.org
+++ b/inventory/host_vars/db-qa01.qa.fedoraproject.org
@@ -34,3 +34,6 @@ mem_size: 8192
 num_cpus: 2
 tcp_ports: [ 5432, 443 ]
 fas_client_groups: sysadmin-qa,sysadmin-noc
+
+# kernel SHMMAX value
+kernel_shmmax: 68719476736
diff --git a/roles/postgresql_server/tasks/main.yml b/roles/postgresql_server/tasks/main.yml
index 1c0ebd3dec..43f3230fb3 100644
--- a/roles/postgresql_server/tasks/main.yml
+++ b/roles/postgresql_server/tasks/main.yml
@@ -14,7 +14,8 @@
   - postgresql
 
 - name: Set kernel shared memory max to a larger value
-  sysctl: name=kernel.shmmax value=68719476736
+  sysctl: name=kernel.shmmax value={{ kernel_shmmax }}
+  when: kernel_shmmax is defined
   notify:
   - restart postgresql
   tags: