Suppose I have two identical virtual machines in Azure, one is constantly running cpu at 100% and the other at 50%. Will the cost for them be the same or will the other be twice the price? This excluding bandwidth and storage.
No, CPU usage doesn't affect the cost you'll pay for the virtual machines. It will be the same for both of them.
Note that if you are using the Free or Shared tiers of Azure Web Sites you have a CPU usage limit.
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