Networks of workstations (NOWs) have become important and cost-effective parallel platforms for scientific computations. In practice, a NOW system is heterogeneous and non-dedicated. These two unique factors make scheduling policies on multiprocessor/multicomputer systems unsuitable for NOWs, but the coscheduling principle is still an important basis for parallel process scheduling in these environments. The main idea of this technique is to schedule the set of tasks composing a parallel application at the same time, to increase their communication performance. In this article we present an explicit coscheduling algorithm implemented in a Linux NOW, of PVM distributed tasks, based on Real Time priority assignment. The main goal of the algorithm is to execute efficiently distributed applications without excessively damaging the response time of local tasks. Extensive performance analysis as well as studies of the parameters and overheads involved in the implementation demonstrated the applicability of the proposed algorithm.