Towards an Understanding of Oversubscription in Cloud
Cloud providers oversubscribe their data centers to leverage unused capacity and to maximize their profits. When a cloud is oversubscribed, overload can happen. For a cloud provider, the key to maximizing profits is to effectively mitigate overload while meeting SLAs promised to the customers. If an SLA is violated, a provider may have to reimburse the customer for any violations. The mechanisms for mitigating overload and the SLAs promised to the customer determine the extent to which a provider can oversubscribe its cloud for maximizing its pro t, and how it should configure and manage spare capacity for mitigating overload.