Parallel computation of radio listening rates

Obtaining the listening rates of radio stations in a function of time is an important instrument for determining the impact of publicity. In order to significantly improve the determination of radio listening rates, special watches have been developed which incorporate a custom integrated circuit sampling the ambient sound during a few seconds every minutes. Each watch accumulates these compressed sound samples during one full week. Watches are then sent to an evaluation center, where the sound samples are matched with the sound samples recorded from candidate radio stations. This paper describes the processing steps necessary for computing the radio listening rates, and shows how this application was parallelized on a cluster of PCs using the computer-aided parallelization framework. The paper describes also the support provided for graceful degradation in a case of transient or permanent failure of one of the system's components. The parallel sound matching server offers a linear speedup up to a large number of processing nodes due to the fact that disk access operations across the network are done in pipeline with computations