Cloud oversubscription system

A method for determining an overload condition for a host in a cloud computing environment, the method comprising:

• measuring a loading value of a virtual machine assigned to a host;
• periodically storing the loading value in a database;
• performing a recursive parameter estimation including at least one summation using the loading values within the database;
• updating the at least one summation at a selective time interval and storing a value of the at least one summation at each selective time interval estimating a probability of overload by:
• a) finding the distribution of the at least one summation at a current time and at least one future time,
• b) finding the probability of overload using estimated model parameters of vector valued-stochastic process model and a capacity of the physical host;
• comparing the probability of overload to an expected availability value;
• and
• recommending an action to take if expected availability value is violated.

A network device comprising a process, a memory coupled with the processor, and an input/output device, the memory comprising executable instructions that when executed by the processor cause the processor to effectuate operations comprising:

• modeling a time series of data for each of at least one host running at least one virtual machine as a vector including at least one model parameter;
• obtaining a resource measurement data for each virtual machine on the host at a selected time interval and estimating the at least one model parameter from the resource measurement data;
• determining a probability of overload based on the at least one model parameter for each of the at least one host;
• obtaining an availability requirement and comparing the probability of overload to the availability requirement;
• and
• taking an action when the probability of overload violates the availability requirement.