diff --git a/demo/alertmanager.yaml b/demo/alertmanager.yaml
index 150988cc0..d38c9a912 100644
--- a/demo/alertmanager.yaml
+++ b/demo/alertmanager.yaml
@@ -12,6 +12,11 @@ route:
       match_re:
         alertname: .*
       continue: true
+    - receiver: "pagination"
+      group_by: ["alertname", "instance"]
+      match_re:
+        alertname: Pagination Test
+      continue: false
     - receiver: "by-cluster-service"
       group_by: ["alertname", "cluster", "service"]
       match_re:
@@ -38,6 +43,7 @@ inhibit_rules:
 
 receivers:
   - name: "default"
+  - name: "pagination"
   - name: "by-cluster-service"
   - name: "by-name"
   - name: "by-cluster"
diff --git a/demo/generator.py b/demo/generator.py
index 2628cb1dd..4ed5bb1e9 100755
--- a/demo/generator.py
+++ b/demo/generator.py
@@ -398,6 +398,21 @@ class SilencedAlertWithJiraLink(AlertGenerator):
         ]
 
 
+class PaginationTest(AlertGenerator):
+    name = "Pagination Test"
+    comment = "Huge number of alerts to test pagination & lazy load"
+
+    def alerts(self):
+        return [
+            newAlert(
+                self._labels(instance="server{}".format(i), cluster="dev",
+                             severity="warning", job="node_exporter",
+                             region="US"),
+                self._annotations(dashboard="https://example.com")
+            ) for i in xrange(0, 1000)
+        ]
+
+
 if __name__ == "__main__":
     generators = [
         AlwaysOnAlert(MAX_INTERVAL),
@@ -412,6 +427,7 @@ if __name__ == "__main__":
         InhibitedAlert(MAX_INTERVAL),
         InhibitingAlert(MAX_INTERVAL),
         SilencedAlertWithJiraLink(MAX_INTERVAL),
+        PaginationTest(MAX_INTERVAL),
     ]
     while True:
         for g in generators: