Performance calculation is a key factor to match corporate goals between different partners in process execution. However, although, a number of standards protocols and languages have recently emerged to support business process services in the industry, there is no standard related to monitoring of performance indicators over processes in these systems. As a consequence, BPMS use propietary languages to define measures and calculate them over process execution. In this paper, we describe two different approaches to compute performance mea- sures on business process decoupled from specific Business Process Man- agement System (BPMS) with an existing BPMS-independent language (PPINOT) to define indicators over business processes. Finally, some optimization techniques are described to increase calculation performance based on computing aggregated measures incrementally.