Incorrect Cinder quota usage shown via CLI/API after Quota Settings Changed

[Bruce Xu]

Reproduce steps:
 1.Update nova quota settings.
    cinder quota-update --volumes vaule TENANT_ID
    cinder quota-update --gigabytes 100 TENANT_ID
   cinder quota-update --snapshots 30 TENANT_ID
 2.Delete the quota settings and the quota should back to the default.
   cinder quota-delete --tenant TENANT_ID

 3.Query nova quota usage
   cinder absolute-limits --tenant tenant_ID
  the usage of volume show "0", it is not correct.

The issue is observed on Havana & icehouse.

[Duncan Thomas (duncan-thomas)]

Exactly what 'delete quotas for a tenant' means is not clearly defined, but I think setting them to zero meets one definition.

Putting them to defaults is somewhat counter intuitive - if you delete somebody's quota and they have quota afterwards (might even be *more* quota than before the delete if the defaults are higher than the override) I'd say that was unexpected.

Might be better to add a separate command to give somebody back default quota(s)?

[Bruce Xu (yunyoxu)]

The main problem is that, when we delete the quota settings, the value of total used volumes/gigabytes/snapshots show "0".
It is strange, since we do not delete any volumes on cinder and the volumes still in use.
The used resource should be not updated when we delete or update the quota.

[Sergey Gotliv (sgotliv)]

Behavior should be consistent across the Openstack. Nova folks on that launchpad[1] (comments 1 and 2) claim
that on Nova master running

nova quota-delete --tenant TENANT_ID

doesn't zero a quota. If its true, I would expect from Cinder to do the same.

[1] https://bugs.launchpad.net/nova/+bug/1410032

[Duncan Thomas (duncan-thomas)]

@sgotliv Are you referencing the right bug there? Comments 1 and two are 'can't reproduce' and 'marking as invalid' followed by a reproducer, no comments there about what the 'correct behaviour should be.

@yunyoxu Resetting the usage record is definitely a bug.

[Mike Perez (thingee)]

If you delete set quotas for a user, I would expect things to fall back to the default.

[Bruce Xu (yunyoxu)]

yes, the quota will fall back to the default when delete the quotas. But the usage recording also reset to "0", that is not correct.
we expect reset the quotas to default and keep the usage as it is.

[Wei T (nuaafe)]

https://bugs.launchpad.net/nova/+bug/1410032 comments added

[Gorka Eguileor (gorka)]

I've been looking into this and it is my understanding that this is a misconception in the implementation.
API clearly states for os-quota-sets delete: "Deletes quotas for a tenant so the quotas revert to default values"
It doesn't say anything about deleting usage or reservations which, as you guys mentioned, are being deleting right now.

If we want to have a way to clear/reset usage/reservations we should have a look into it, although I can't think right now of a good reason why we would need it. For now we should fix this.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/162722

[Gorka Eguileor (gorka)]

Thread in the mail list on this topic: http://lists.openstack.org/pipermail/openstack-dev/2015-April/061000.html

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/162722
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=0ee1ea83b90de8d342fa242e311f1680fef66a92
Submitter: Jenkins
Branch: master

commit 0ee1ea83b90de8d342fa242e311f1680fef66a92
Author: Gorka Eguileor <email address hidden>
Date: Mon Mar 9 19:39:11 2015 +0100

    Preserve usage and reservations on quota deletion

    Current API deletes quota usage and reservations on quota limit
    deletion.

    According to API documentation what should only happen is that quotas
    limits revert to default values by deleting tenant/user limits.

    This patch fixes this issue.

    APIImpact: Delete on os-quota-sets will no longer remove usage and
               reservation quotas. Those quotas are handled by Cinder
               service.
    UpgradeImpact: There is no upgrade impact afaik.
    Closes-Bug: #1410034
    Change-Id: I9340b6f78623cfa5b505886ad75b8e4d3cd6131b

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/kilo
Review: https://review.openstack.org/189588

[OpenStack Infra (hudson-openstack)]

Change abandoned by Gorka Eguileor (<email address hidden>) on branch: stable/kilo
Review: https://review.openstack.org/189588