diff --git a/neutron/common/metadata.py b/neutron/common/metadata.py
index 7fe08180718..f206df43a8d 100644
--- a/neutron/common/metadata.py
+++ b/neutron/common/metadata.py
@@ -45,6 +45,7 @@ global
     user        %(user)s
     group       %(group)s
     maxconn     1024
+    nbthread    2
     pidfile     %(pidfile)s
     daemon
 
diff --git a/releasenotes/notes/haproxy-nbthread-a658040c98639b47.yaml b/releasenotes/notes/haproxy-nbthread-a658040c98639b47.yaml
new file mode 100644
index 00000000000..ee47fcb3666
--- /dev/null
+++ b/releasenotes/notes/haproxy-nbthread-a658040c98639b47.yaml
@@ -0,0 +1,8 @@
+---
+fixes:
+  - |
+    Limit the number of threads used by the metadata haproxy service to 2 using
+    the nbthread configuration. This prevents haproxy from spreading across many
+    threads when the process lacks other restrictions like CPU affinity.
+    For more information, see bug
+    `2120668 <https://bugs.launchpad.net/neutron/+bug/2120668>`_.
\ No newline at end of file