diff --git a/keystone/map.jinja b/keystone/map.jinja
index 35a2613..01dc3f4 100644
--- a/keystone/map.jinja
+++ b/keystone/map.jinja
@@ -62,6 +62,7 @@
 {% set monitoring = salt['grains.filter_by']({
     'default': {
         'error_log_rate': 0.2,
+        'http_response_time_p90': 0.3,
         'failed_auths': {
             'percentage': 50,
             'all_auths_rate': 0.1,
diff --git a/keystone/meta/prometheus.yml b/keystone/meta/prometheus.yml
index d584553..fc3568f 100644
--- a/keystone/meta/prometheus.yml
+++ b/keystone/meta/prometheus.yml
@@ -49,5 +49,17 @@
       annotations:
         summary: 'Too many failed authentications in Keystone'
         description: 'The rate of failed authentications in Keystone over the last 5 minutes is too high (current value={{ $value }}, threshold={%- endraw %}{{ auth_threshold }}).'
+    KeystoneAPITooSlow:
+      {%- set response_time_threshold = monitoring.http_response_time_p90|float %}
+      if: >-
+        max by(host) (openstack_keystone_http_response_times_upper_90{http_method=~"^(GET|POST)$",http_status="2xx"}) >= {{ response_time_threshold }}
+{%- raw %}
+      for: 2m
+      labels:
+        severity: warning
+        service: keystone
+      annotations:
+        summary: 'Keystone API too slow'
+        description: 'The 90th percentile of the Keystone API response times for GET and POST requests is too high on node {{ $labels.host }} (current value={{ $value }}s, threshold={%- endraw %}{{ response_time_threshold }}s).'
 
 {%- endif %}