1. A computer implemented method for service demand based performance prediction of an application under test with varying workloads, the method comprising: identifying a predetermined range of concurrencies in the application under test; computing an optimum number of load testing points for interpolation within the identified range of concurrencies, the load testing points comprising Chebyshev nodes within the predetermined range; computing concurrency levels at the computed load testing points; generating service demand samples at the computed concurrency levels; generating an array of interpolated service demands for the identified range of concurrencies based on the computed optimum number of load testing points and the generated service demand samples; computing throughput and response time for the identified range of concurrencies based on the generated array of interpolated service demands; and generating and outputting a performance profile for the application for use in optimizing the application, the performance profile including the computed throughput and response time.