Empty Disk Image attachment is taking too long time

Community Support
1

We have Opennebula configured and successfully added few hosts and deployed VMs.

To build an image, we required to attach add-on disk of 50GB to the VM.

For Add-on Disk We created an Empty disk image with below details

Type - DATABLOCK
Persistent : no
Attributes
DEV_PREFIX vd
DRIVER raw
TOTAL_IOPS_SEC 5000

Actual Issue

  • Add-on Disk attachment taking too much time.

Since its empty disk it should consider zeroing. However I could see dd clone process is taking place.

PS : This is test environment and we request to provide any alternatives to disable this or any alternatives to attach disk faster.

2

Hello @indjas

By default, OpenNebula may perform a full dd operation to initialize disks.

You can try 2 options, but there could be some issues around Data Security (however, since it’s a new empty disk, it won’t affect your case):

  1. Use Sparse Files (more info on the doc: Local Storage Datastore)
  2. Use QCOW2 Format (more info: Image Template, or Creating Disk Images)

In any case, you can search on our documentation for more info.

Regards,