diff --git a/defaults/main.yml b/defaults/main.yml
index b6b27d44..8684796e 100644
--- a/defaults/main.yml
+++ b/defaults/main.yml
@@ -108,6 +108,10 @@ ceilometer_service_in_ldap: false
 # ceilometer_collector_workers: 1
 # ceilometer_notification_workers: 1
 
+## Cap the maximum number of threads / workers when a user value is unspecified.
+ceilometer_api_threads_max: 16
+ceilometer_api_threads: "{{ [[ansible_processor_vcpus|default(2) // 2, 1] | max, ceilometer_api_threads_max] | min }}"
+
 # Enable/Disable Ceilometer per service
 glance_ceilometer_enabled: false
 nova_ceilometer_enabled: false
diff --git a/releasenotes/notes/capping_ceilometer_workers-80a768e3aaed0aec.yaml b/releasenotes/notes/capping_ceilometer_workers-80a768e3aaed0aec.yaml
new file mode 100644
index 00000000..e8cc2021
--- /dev/null
+++ b/releasenotes/notes/capping_ceilometer_workers-80a768e3aaed0aec.yaml
@@ -0,0 +1,6 @@
+---
+features:
+  - Capping the default value for the variables
+    ``ceilometer_api_workers`` and ``ceilometer_notification_workers`` to
+    16 when the user doesn't configure these variables. Default value is half
+    the number of vCPUs available on the machine with a capping value of 16.
diff --git a/templates/ceilometer.conf.j2 b/templates/ceilometer.conf.j2
index fa32900e..fc051314 100644
--- a/templates/ceilometer.conf.j2
+++ b/templates/ceilometer.conf.j2
@@ -1,8 +1,5 @@
 #{{ ansible_managed}}
 
-{% set _workers = ansible_processor_vcpus|default(2) // 2 %}
-{% set workers = _workers if _workers > 0 else 1 %}
-
 [DEFAULT]
 # Disable stderr logging
 use_stderr = False
@@ -33,7 +30,7 @@ rabbit_use_ssl = {{ ceilometer_rabbitmq_use_ssl }}
 
 [api]
 gnocchi_is_enabled = {{ ceilometer_gnocchi_enabled | bool }}
-workers = {{ ceilometer_api_workers | default(workers) }}
+workers = {{ ceilometer_api_workers | default(ceilometer_api_threads) }}
 port = 8777
 
 [collector]
@@ -44,7 +41,7 @@ batch_timeout = 5
 {% endif %}
 
 [notification]
-workers = {{ ceilometer_notification_workers | default(workers) }}
+workers = {{ ceilometer_notification_workers | default(ceilometer_api_threads) }}
 store_events = {{ not ceilometer_gnocchi_enabled | bool }}
 
 # Notification queues to listen on