Vehicular ad hoc networks (VANETs) are the flaming topic of research. VANET comprises of moving vehicles communicating with each other. VANETs involve three types of communication: vehicle to vehicle (V2V), vehicle to roadside (V2R) or vehicle to infrastructure (V2I) communication. VANETs consist of some vital components: RSU, OBU and Trusted Authority. Among them Roadside units (RSUs) are one of the fundamental components of Vehicular ad hoc network (VANET). Roadside Units (RSUs) are placed across the road for infrastructure communication. But the deployment cost of RSUs is very high, so to deploy more and more number of RSUs across roads is quite expensive. Thus, there is a need to optimally place a limited number of RSUs in a given region or road in order to achieve maximum performance. In this paper, we present a solution to this problem using parallel processing. A so-called scalable TDB based RSUs deployment algorithm with a goal of minimizing the parallel time taken to place roadside units in a given area and to attain high efficiency and cover maximum area has been presented. The performance of the proposed algorithm and optimization strategy is assessed by evaluating different parameters like efficiency, power consumption, serial elapsed time, parallel elapsed time, speedup and overheads incurred in running the algorithm in parallel.