From c35faf4cbcd3ee7d4a069368be5c6655f22758fa Mon Sep 17 00:00:00 2001
From: James Page <james.page@ubuntu.com>
Date: Wed, 14 Mar 2018 17:42:56 +0000
Subject: [PATCH] Auto-configure WSGI worker processes

Automatically configure WSGI worker processes inline with other
charms using the worker-multiplier configuration option and the
WSGI worker configuration context from charm-helpers.

Change-Id: Ib8af4a5a54fcff13a05ba4f4094bf123d5282c4a
---
 config.yaml                                 | 9 +++++++++
 hooks/horizon_utils.py                      | 6 ++++--
 templates/icehouse/openstack-dashboard.conf | 2 +-
 templates/newton/openstack-dashboard.conf   | 2 +-
 templates/ocata/openstack-dashboard.conf    | 2 +-
 templates/pike/openstack-dashboard.conf     | 2 +-
 6 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/config.yaml b/config.yaml
index b3da5630..e9d747ef 100644
--- a/config.yaml
+++ b/config.yaml
@@ -348,3 +348,12 @@ options:
       .
       If not provided, leave the option unconfigured which enables all of the
       above.
+  worker-multiplier:
+    type: float
+    default:
+    description: |
+      The CPU core multiplier to use when configuring worker processes for
+      Horizon. By default, the number of workers for each daemon is set to
+      twice the number of CPU cores a service unit has. When deployed in
+      a LXD container, this default value will be capped to 4 workers
+      unless this configuration option is set.
diff --git a/hooks/horizon_utils.py b/hooks/horizon_utils.py
index c5014e76..0af36725 100644
--- a/hooks/horizon_utils.py
+++ b/hooks/horizon_utils.py
@@ -98,12 +98,14 @@ CONFIG_FILES = OrderedDict([
     }),
     (APACHE_CONF, {
         'hook_contexts': [horizon_contexts.HorizonContext(),
-                          context.SyslogContext()],
+                          context.SyslogContext(),
+                          context.WSGIWorkerConfigContext()],
         'services': ['apache2', 'memcached'],
     }),
     (APACHE_24_CONF, {
         'hook_contexts': [horizon_contexts.HorizonContext(),
-                          context.SyslogContext()],
+                          context.SyslogContext(),
+                          context.WSGIWorkerConfigContext()],
         'services': ['apache2', 'memcached'],
     }),
     (APACHE_SSL, {
diff --git a/templates/icehouse/openstack-dashboard.conf b/templates/icehouse/openstack-dashboard.conf
index 634cddae..28a1dc03 100644
--- a/templates/icehouse/openstack-dashboard.conf
+++ b/templates/icehouse/openstack-dashboard.conf
@@ -1,5 +1,5 @@
 WSGIScriptAlias {{ webroot }} /usr/share/openstack-dashboard/openstack_dashboard/wsgi/django.wsgi
-WSGIDaemonProcess horizon user=horizon group=horizon processes=3 threads=10
+WSGIDaemonProcess horizon user=horizon group=horizon processes={{ processes }} threads=10
 WSGIProcessGroup horizon
 Alias /static /usr/share/openstack-dashboard/openstack_dashboard/static/
 Alias /horizon/static /usr/share/openstack-dashboard/openstack_dashboard/static/
diff --git a/templates/newton/openstack-dashboard.conf b/templates/newton/openstack-dashboard.conf
index 634cddae..28a1dc03 100644
--- a/templates/newton/openstack-dashboard.conf
+++ b/templates/newton/openstack-dashboard.conf
@@ -1,5 +1,5 @@
 WSGIScriptAlias {{ webroot }} /usr/share/openstack-dashboard/openstack_dashboard/wsgi/django.wsgi
-WSGIDaemonProcess horizon user=horizon group=horizon processes=3 threads=10
+WSGIDaemonProcess horizon user=horizon group=horizon processes={{ processes }} threads=10
 WSGIProcessGroup horizon
 Alias /static /usr/share/openstack-dashboard/openstack_dashboard/static/
 Alias /horizon/static /usr/share/openstack-dashboard/openstack_dashboard/static/
diff --git a/templates/ocata/openstack-dashboard.conf b/templates/ocata/openstack-dashboard.conf
index 81055d06..e22b3cfa 100644
--- a/templates/ocata/openstack-dashboard.conf
+++ b/templates/ocata/openstack-dashboard.conf
@@ -1,5 +1,5 @@
 WSGIScriptAlias {{ webroot }} /usr/share/openstack-dashboard/openstack_dashboard/wsgi/django.wsgi
-WSGIDaemonProcess horizon user=www-data group=www-data processes=3 threads=10
+WSGIDaemonProcess horizon user=www-data group=www-data processes={{ processes }} threads=10
 WSGIProcessGroup horizon
 Alias /static /var/lib/openstack-dashboard/static/
 Alias /horizon/static /var/lib/openstack-dashboard/static/
diff --git a/templates/pike/openstack-dashboard.conf b/templates/pike/openstack-dashboard.conf
index 053625fd..99feddfb 100644
--- a/templates/pike/openstack-dashboard.conf
+++ b/templates/pike/openstack-dashboard.conf
@@ -1,5 +1,5 @@
 WSGIScriptAlias {{ webroot }} /usr/share/openstack-dashboard/openstack_dashboard/wsgi/django.wsgi
-WSGIDaemonProcess horizon user=horizon group=horizon processes=3 threads=10
+WSGIDaemonProcess horizon user=horizon group=horizon processes={{ processes }} threads=10
 WSGIProcessGroup horizon
 Alias /static /var/lib/openstack-dashboard/static/
 Alias /horizon/static /var/lib/openstack-dashboard/static/