From 056c3254865193b95bf85fa520825fe3855371bc Mon Sep 17 00:00:00 2001
From: "Joshua M. Boniface" <joshua@boniface.me>
Date: Fri, 1 Sep 2023 15:42:28 -0400
Subject: [PATCH] Add option for setting CPU governor

Allows the administrator to set a CPU frequency governor if they need
to, though the default of ondemand is usually sufficient.
---
 group_vars/default/base.yml                   |  4 ++++
 roles/base/defaults/main.yml                  |  2 ++
 roles/base/tasks/main.yml                     | 21 +++++++++++++++++--
 .../templates/etc/default/cpufrequtils.j2     |  3 +++
 roles/base/templates/etc/default/locale.j2    |  2 ++
 5 files changed, 30 insertions(+), 2 deletions(-)
 create mode 100644 roles/base/templates/etc/default/cpufrequtils.j2

diff --git a/group_vars/default/base.yml b/group_vars/default/base.yml
index 9302110..073fe69 100644
--- a/group_vars/default/base.yml
+++ b/group_vars/default/base.yml
@@ -19,6 +19,10 @@ recursive_dns_search_domains:
 # Cluster hardware model, used in pvc_user_configuration and grub_configuration below
 cluster_hardware: default
 
+# CPU governor, sets power and performance statistics of the system CPUs; default is ondemand
+# > Valid options are (usually): conservative, ondemand, powersave, userspace, performance, schedutil
+cpu_governor: ondemand
+
 # Debian package repository URL
 debian_main_repository: http://ftp.debian.org/debian
 debian_security_repository: http://security.debian.org
diff --git a/roles/base/defaults/main.yml b/roles/base/defaults/main.yml
index a6a6c57..556f952 100644
--- a/roles/base/defaults/main.yml
+++ b/roles/base/defaults/main.yml
@@ -19,3 +19,5 @@ deploy_username: "deploy"
 
 fail2ban_ignorelist:
   - 10.0.0.0/8
+
+cpu_governor: "ondemand"
diff --git a/roles/base/tasks/main.yml b/roles/base/tasks/main.yml
index 3f80727..81f29ea 100644
--- a/roles/base/tasks/main.yml
+++ b/roles/base/tasks/main.yml
@@ -251,6 +251,7 @@
       - lzop
       - xz-utils
       - haveged
+      - cpufrequtils
       - ipmitool
       - grub-efi
       - plymouth
@@ -324,6 +325,21 @@
     - /etc/sysctl.d/pvc.conf
   tags: base-system
 
+# cpufreq
+- name: write the cpufrequtils governor
+  template:
+    src: etc/default/cpufrequtils.j2
+    dest: /etc/default/cpufrequtils
+  register: cpufrequtils
+  tags: base-system
+
+- name: activate cpufrequtils governor
+  service:
+    name: cpufrequtils
+    state: restarted
+  when: cpufrequtils.changed
+  tags: base-system
+
 # sudo
 - name: write the sudoers file
   template:
@@ -963,9 +979,10 @@
     enabled: yes
   with_items:
     - acpid
-    - rsyslog
-    - postfix
+    - cpufrequtils
     - ntp
+    - postfix
+    - rsyslog
     - ssh
   tags: base-services
 
diff --git a/roles/base/templates/etc/default/cpufrequtils.j2 b/roles/base/templates/etc/default/cpufrequtils.j2
new file mode 100644
index 0000000..dcaf142
--- /dev/null
+++ b/roles/base/templates/etc/default/cpufrequtils.j2
@@ -0,0 +1,3 @@
+# CPU Frequency Utils configuration
+# {{ ansible_managed }}
+GOVERNOR="{{ cpu_governor }}"
diff --git a/roles/base/templates/etc/default/locale.j2 b/roles/base/templates/etc/default/locale.j2
index 3944c9a..6b33922 100644
--- a/roles/base/templates/etc/default/locale.j2
+++ b/roles/base/templates/etc/default/locale.j2
@@ -1,3 +1,5 @@
+# Locales configuration
+# {{ ansible_managed }}
 LANGUAGE=en_CA.UTF-8
 LC_ALL=en_CA.UTF-8
 LANG=en_CA.UTF-8