Quota calulated when instance poweroff

[LiweiWang]

Description
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When I powered off an instance, I hope to start another, but there is a quota limit told me that I can not build more instance beacuse there is no more ram or cpus. I thought that it is not reasonable. This leads to a waste of physical resources.

[Matt Riedemann (mriedem)]

This is working as designed. The guest might be gone from the hypervisor while the instance is shutdown, but nova continues to track quota against that instance, otherwise you potentially can't start the instance later if someone in the same project took the quota you were using in the meantime while your instance was stopped.

[LiweiWang (wlw9001)]

Rather than deleting a powered off instance, I may want to keep it (because I will use it later). But I could not start anthor instance, when there are free cup or ram in fact. Isn't that a waste?

[Sylvain Bauza (sylvain-bauza)]

Matt already explained the design consensus about why we still consume the resources for the quota even if they are poweroff.

For your usecase, you can snapshot the instance and then delete it (like before the week-end).