1. A method for estimating cloud computing resource costs required to process a workload to be completed, comprising: receiving historical trace data of at least one processed workload that is similar to the workload to be completed; simulating processing of the to be completed workload using a t-shirt cloud computing model applied to the historical trace data; estimating a t-shirt resource cost based on the simulation of the completed workload using the t-shirt cloud computing model; simulating the processing of the to be completed workload using a time-sharing cloud computing model applied to the historical data; estimating a time-sharing resource cost based on the simulation of the completed workload using the time-sharing cloud computing model; and comparing the t-shirt resource cost to the time-sharing resource cost to determine the more efficient cloud computing model to process the to be completed workload.