Set default metadata backlog to 4096

We already optimize the metadata agent by running it in multi-workers,
we need by default to set the metadata backlog value.
Inspired from 19:34: https://www.youtube.com/watch?v=AF9r_VQrcJ0
and https://review.openstack.org/#/c/95372

Change-Id: I68f3414ef56290ca27d11f8cf26febc100741d46
Signed-off-by: Emilien Macchi <[email protected]>
(cherry picked from commit 1055a12)

Author: Emilien Macchi

manifests/agents/metadata.pp

@@ -55,6 +55,10 @@
 #   The parent process manages them. Having more workers will help to improve performances.
 #   Defaults to: 0
 #
+# [*metadata_backlog*]
+#   (optional) Number of backlog requests to configure the metadata server socket with.
+#   Defaults to 4096
+#
 
 class neutron::agents::metadata (
   $auth_password,
@@ -71,7 +75,8 @@
   $auth_region      = 'RegionOne',
   $metadata_ip      = '127.0.0.1',
   $metadata_port    = '8775',
-  $metadata_workers = '0'
+  $metadata_workers = '0',
+  $metadata_backlog = '4096'
   ) {
 
   include neutron::params
@@ -92,6 +97,7 @@
     'DEFAULT/nova_metadata_port':             value => $metadata_port;
     'DEFAULT/metadata_proxy_shared_secret':   value => $shared_secret;
     'DEFAULT/metadata_workers':               value => $metadata_workers;
+    'DEFAULT/metadata_backlog':               value => $metadata_backlog;
   }
 
   if $auth_ca_cert {

spec/classes/neutron_agents_metadata_spec.rb

@@ -19,6 +19,7 @@
       :metadata_ip      => '127.0.0.1',
       :metadata_port    => '8775',
       :metadata_workers => '2',
+      :metadata_backlog => '4096',
       :shared_secret    => 'metadata-secret'
     }
   end
@@ -57,6 +58,7 @@
       should contain_neutron_metadata_agent_config('DEFAULT/nova_metadata_ip').with(:value => params[:metadata_ip])
       should contain_neutron_metadata_agent_config('DEFAULT/nova_metadata_port').with(:value => params[:metadata_port])
       should contain_neutron_metadata_agent_config('DEFAULT/metadata_workers').with(:value => params[:metadata_workers])
+      should contain_neutron_metadata_agent_config('DEFAULT/metadata_backlog').with(:value => params[:metadata_backlog])
       should contain_neutron_metadata_agent_config('DEFAULT/metadata_proxy_shared_secret').with(:value => params[:shared_secret])
     end
   end