Set memcache connection limit to 5000

Change-Id: I5599389f26a8ce54bbd0dfc480879d62c7a5ad1d
Closes-Bug: #1633169

ansible/roles/memcached/defaults/main.yml

@@ -7,3 +7,8 @@ project_name: "memcached"
 memcached_image: "{{ docker_registry ~ '/' if docker_registry else '' }}{{ docker_namespace }}/{{ kolla_base_distro }}-{{ kolla_install_type }}-memcached"
 memcached_tag: "{{ openstack_release }}"
 memcached_image_full: "{{ memcached_image }}:{{ memcached_tag }}"
+
+####################
+# Memcached options
+####################
+memcached_connection_limit: "5000"

ansible/roles/memcached/templates/memcached.json.j2

 {
-    "command": "/usr/bin/memcached -vv -l {{ api_interface_address }} -p {{ memcached_port }}"
+    "command": "/usr/bin/memcached -vv -l {{ api_interface_address }} -p {{ memcached_port }} -c {{ memcached_connection_limit }}",
+    "config_files": []
 }