OpenStack Xena
CentOS 8 Stream
My task is to increase from 16 vCPU to 32 vCPU. I'm trying to overcommit, but it doesn't work.
I have one controller and one compute.
Compute output:
[root@controller ~(keystone)]# openstack hypervisor stats show
+----------------------+-------+
| field | value |
+----------------------+-------+
| count | 1 |
| current_workload | 0 |
| disk_available_least | 62 |
| free_disk_gb | 69 |
| free_ram_mb | 31326 |
| local_gb | 69 |
| local_gb_used | 0 |
| memory_mb | 31838 |
| memory_mb_used | 512 |
| running_vms | 0 |
| vcpus | 16 |
| vcpus_used | 0 |
+----------------------+-------+
On compute in /etc/nova/nova.conf by default:
# Virtual CPU to physical CPU allocation ratio. For more information, refer to
# the documentation. (floating point value)
# Minimum value: 0.0
#cpu_allocation_ratio=<None>
I did this: cpu_allocation_ratio=2.0
, then systemctl restart openstack-nova-compute
. After that I did openstack hypervisor stats show
again and saw that 16 vCPUs were still available.
/etc/nova/nova.conf also has an option:
#
# Initial virtual CPU to physical CPU allocation ratio. For more information,
# refer to the documentation. (floating point value)
# Minimum value: 0.0
#initial_cpu_allocation_ratio=16.0
I tried setting initial_cpu_allocation_ratio=32.0
, but that didn't help either.
In addition, I found only such documentation on overcommitting https://docs.openstack.org/arch-design/design-compute/design-compute-overcommit.html , but it does not say how to configure it correctly.