The starting point for most is the core count of your
cloud. By applying some ratios, you can gather information
about the number of virtual machines (VMs) you expect to
((overcommit fraction × cores) / virtual cores
per instance), how much storage is required
(flavor disk size × number of instances).
You can use these ratios to determine how much additional
infrastructure you need to support your cloud.
Core Count to VM instances Math
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