Manila share and share snapshot deferred deletion


Manila does not support the deferred deletion of share and share snapshots. This blueprint is to add support for share and share snapshot deferred deletion. The end user will delete the share and share snapshot using API and then Manila will perform the deferred deletion of the share and share snapshot respectively thereby freeing quota immediately.

Problem description

If users want to remove a share or share snapshot from Manila, it is possible to delete them using API. The manila-API part of deletion procedure finishes quickly, on the other hand the backend driver takes time. The quotas allocated to the share or share snapshot are not freed until share or share snapshot are deleted completely. This increases waiting time for creation of new share or share snapshot. Providing a way to release the quota immediately and perform deferred deletion will solve this issue. Also automated workflows face problem in creation of new shares and/or share snapshots where they have to wait until quota is available after share or share snapshot is deleted by backend driver.

Use Cases

  • In automated workflows where deletion of share/share-snapshot is an intermediate step, have to wait until share/share-snapshot is deleted. Defer deletion allows automation to proceed without waiting for driver.

  • The user want to delete share/share-snapshot and check the available share/share-snapshot and their corresponding gigabytes quota.

Proposed change

The following are the changes to be made:

  • A new status values ‘DELETING_IN_DRIVER’ and ‘DELETING_IN_DRIVER_ERROR’ will be introduced to identify share instances which will be processed in deferred deletion.

  • Add new configuration option ‘deferred_deletion’, which means if TRUE the shares are deleted in deferred deletion manner, and if FALSE the share will be deleted the way it is happening today.

  • As soon as share or share-snapshot is deleted by API request, the quota will be reclaimed and share/share-snapshot instance will be moved to ‘DELETING_IN_DRIVER’ state. Any delete request on share/share-snapshot while it is in ‘DELETING_IN_DRIVER’ state, will return error. A periodic task running every 300 seconds will be added in share manager, which gets all share instances in ‘DELETING_IN_DRIVER’ state. The share manager, will then call backend driver to delete the share/share-snapshot instance and move it to ‘DELETED’ state on successful deletion. Any failure during deletion, will move share/share-snapshot instance in the ‘DELETING_IN_DRIVER_ERROR’ state. Only admin can list those shares/share-snapshots and then delete/cleaup them on storage, where they will be marked as ‘DELETED’. The periodic task also checks for share/share-snapshot in the ‘DELETING_IN_DRIVER_ERROR’ state and tries to delete them again after 30 minutes of previous attempt.

  • No change in backend driver.


Instead of adding new status value, we can mark share/share-snapshot as ‘DELETED’ immediately and move those shares/share-snapshots to another project. This project will contain only deleted shares/share-snapshots by manila API service. The share manager will run a periodic task to delete share and share-snapshot from this project. In this case as well since quota is reclaimed earlier, share manager will make sure share instance must be deleted by backend driver.

An issue with this approach is we will change project id of original share during deletion which can be unwanted data modification.

Data model impact

  • No change in share instance table except introduction of two more values for ‘status’ field.

CLI API impact


REST API impact

Shares and share snapshots in ‘deleting_in_driver_error’ state are not visible to regular user. Only admins can list/show those shares and share snapshots because they can react to such error like cleaning up them.

Driver impact


Security impact


Notifications impact


Other end user impact

If configured, instead of ‘deleting’ and ‘deleting_error’ states, end user will now see ‘deleting_in_driver’ and ‘deleting_in_driver_error’ states respectively. Also, end user will observe that share in ‘deleting_in_driver’ state has freed its quota immediately.

The cloud admins can list shares in the new state(s) via API.

Performance Impact


Other deployer impact


Developer impact




Primary assignee:

Work Items

  • Implement periodic share manager function to process deferred deletion.

  • Implement tempest support.

Future Work Items





  • Unit tests

  • Tempest tests

Documentation Impact

  • Docstrings

  • Devref

  • User guide

  • Admin guide

  • Release notes