International Journal of Computer Science Issues

More than a traditional journal...

Scheduled algorithms in disc, have a very important role in real time applications used in multimedia, in as much as the last ones generate I/O demands with their restrictions in real time. Both traditional algorithms and other two ones mentioned later during this study, serve to real-time tasks according their deadlines. However, reaching the goal is also accompanied with costs causing in main parameters such as: searching time in the disc, rotation time, the time in which discs head stays totally free, overhead during transmission, disk utilization, throughput and response time to non periodic tasks. The aim of this study consists on determining the best algorithm on parameters accomplishing and, as well as the definition of parameter they try to optimize in particular. WRR-SCAN spends less time during the search through disc, while SCAN-EDF generates less disc rotations. Compared to SCAN-EDF, WRR-SCAN reduces a lot overhead during no-transmission, increases disc usage and offers an affordable response time toward non periodic tasks