- By default in Platform9 Managed OpenStack, instances ephemeral disks are thin-provisioned, meaning that no disk space is allocated upfront. For performance reasons, one may want to preallocate this disk on the underlying filesystem or otherwise use "thick" provisioning.
- Platform9 Managed OpenStack
1. Set the following on each compute host where thick provisioning should be enabled.
preallocate_images = space
2. Restart the compute service.
# service pf9-ostackhost restart
For any newly-created instances, the disk file will now be expanded. Any existing instances will remain to be thin-provisioned.
For more details on this option and why it should be enabled, please refer: OpenStack Docs - Nova - Configuration Options.