nova shows wrong RAM usage

[int32bit]

If flavor has hw_video:ram_max_mb value, nova will add this value to the project usage[1]. But when we delete this server, it seems we don't cover this case. So we will always get wrong ram usage.

For example, we create a server with flavor f, whose ram is 1024 and hw_video:ram_max_mb is 64, then we will compute quota usage as 1024 + 64, but when we delete this server, we only release 1024, rather than 1024 + 64. As a result, the usage may incremente constantly， until over max limit.

[1] https://github.com/openstack/nova/blob/master/nova/compute/api.py#L352-L353

[int32bit (int32bit)]

Obviously, we can't get hw_video from flavor, because the flavor will be changed by user. I think we need add hw_video:ram_max_mb to the server metadata, and read this value when delete server. Or we just ignore hw_video when create a new sever.

[Matt Riedemann (mriedem)]

Is this related to https://review.openstack.org/#/c/463148/ ?