Ensure CPU tuning is only applied on Debian 11+

group_vars/default/pvc.yml

@@ -153,6 +153,7 @@ pvc_sriov_enable: False
 # > ADVANCED TUNING: These options are strongly recommended due to the performance gains possible, but
 #   most users would be able to use the default without too much issue. Read the following notes
 #   carefully to determine if this setting should be enabled in your cluster.
+# > NOTE: CPU tuning is only supported on Debian Bullseye (11) or newer
 # > Defines CPU tuning/affinity options for various subsystems within PVC. This is useful to
 #   help limit the impact that noisy elements may have on other elements, e.g. busy VMs on
 #   OSDs, or system processes on latency-sensitive VMs.

roles/base/defaults/main.yml

@@ -12,7 +12,7 @@ recursive_dns_servers:
 recursive_dns_search_domains:
   - "{{ local_domain }}"
 
-grub_cmdline: "systemd.unified_cgroup_hierarchy=1 console=tty0 console=ttyS{{ grub.serial_console[cluster_hardware].console }},115200 plymouth.ignore-serial-consoles splash"
+grub_cmdline: "console=tty0 console=ttyS{{ grub.serial_console[cluster_hardware].console }},115200 plymouth.ignore-serial-consoles splash"
 grub_serial: "serial --unit={{ grub.serial_console[cluster_hardware].console }} --speed=115200"
 
 deploy_username: "deploy"

roles/base/templates/etc/default/grub.j2

@@ -3,7 +3,11 @@
 GRUB_DEFAULT=0
 GRUB_TIMEOUT=5
 GRUB_DISTRIBUTOR="PVC Parallel Virtual Cluster - Debian"
+{% if ansible_distribution_major_version|int >= 11 %}
+GRUB_CMDLINE_LINUX="systemd.unified_cgroup_hierarchy=1 {{ grub_cmdline }}"
+{% else %}
 GRUB_CMDLINE_LINUX="{{ grub_cmdline }}"
+{% endif %}
 GRUB_TERMINAL_INPUT="console serial"
 GRUB_TERMINAL_OUTPUT="gfxterm serial"
 GRUB_SERIAL_COMMAND="{{ grub_serial }}"

roles/pvc/tasks/main.yml

@@ -59,7 +59,7 @@
 # Install CPU tuning
 - include: cputuning/main.yml
   tags: pvc-cputuning
-  when: cpu_tuning is defined
+  when: ansible_distribution_major_version|int >= 11 and cpu_tuning is defined
 
 - name: restart server on first install
   shell: 'sleep 3 && shutdown -r now "Ansible updates triggered"'