A method and system for testing performance of a software product. One or more complete executions of a performance test of corresponding versions of the software product are performed. The complete executions of the performance test identifies a steady state value of each performance parameter monitored during the performance test after each performance parameter has transitioned to a steady state during the performance test. A performance profile of the software product is determined according to the complete executions of the performance test. Partial executions of the performance test of corresponding further versions of the software product are performed, each partial execution having a partial duration preceding the steady state of each performance parameter. Corresponding results of the partial executions of the performance test are estimated according to the performance profile from corresponding partial trends of each performance parameter during the partial executions of the performance test.