Merge "Manage QEMU driver cgroups by monolithic libvirtd" into stable/wallaby

deployment/deprecated/nova/nova-libvirt-container-puppet.yaml

@@ -521,7 +521,7 @@ outputs:
                 if [[ -f /usr/lib/systemd/kvm-setup ]]; then
                   /usr/lib/systemd/kvm-setup
                 fi
-                exec systemd-run --scope --slice=system /usr/sbin/libvirtd LIBVIRTD_ARGS
+                exec systemd-run --scope --slice=system --property=Delegate="cpu cpuacct memory blkio devices" /usr/sbin/libvirtd LIBVIRTD_ARGS
               params:
                 LIBVIRTD_ARGS:
                   if:

releasenotes/notes/nova_libvirt_cgroups-66b173a758ced3f2.yaml

@@ -0,0 +1,15 @@
+---
+upgrade:
+  - |
+    To re-enable the QEMU driver features lost after the previous minor update,
+    such as `virsh cpu-stats`, or volume attachements for existing Nova Compute
+    instances, those need to be live-migrated (or cold-migrated) to either of
+    the newly updated Nova Compute hosts.
+fixes:
+  - |
+    Tripleo Nova Libvirt service unit no longer manages the QEMU driver cgroups
+    by systemd, but delagates that to libvirt. In a result, newly created Nova
+    Compute instances no longer experience problems with volume attachements,
+    or executing virsh commands in the libvirt podman container, after the
+    libvirt service restarts multiple times.
+