No improvement without feedback: Experiences from goal-oriented measurement at Schlumberger

Schlumberger is an international technology oriented company and started its company wide software process improvement program in 1989. This industrial experience paper describes how goal-oriented measurement was established and which role feedback sessions played as a critical success factor within this process. By feedback sessions we mean well-organized, structured meetings between the project team and the measurement team. Main objective is to review the data collected so far and to analyze and interpret it. The interpretations derived are fed back both into the software development process and into the measurement process. Thus, feedback sessions serve multiple purposes: they maintain motivation and momentum in the measurement program, they ensure that the interpretations derived from the collected data are correct, and they allow the identification of small-scale changes that can be immediately implemented in order to improve both the measurement and the software development process. In addition to that, the interpretations derived from the data allow identification of larger-scale changes to the software development process which can be implemented and validated in subsequent software projects. We describe practical experiences with feedback sessions based on two projects: the Omega 2010 project for development of both hardware and software for a point-of-sale system with quality focus on reliability and reusability, and the DEMP project with quality focus on interrupt handling. The experience report will give detailed answers to pragmatic questions, such as, how feedback sessions were prepared, how they were performed, which results were derived, and which lessons were learned for future projects. As a main conclusion, feedback sessions are characterized as the back-bone of any industrial measurement program.