One of the functions of the Operating System is serve the pending I/O requests from disk queue to the
requesting processes. Once a request is served, the operating system has to determine which request will be
served next. This process involves a careful examination of pending requests to determine the most efficient
way to service the requests. The aim of most of the disk scheduling algorithms is to reduce seek times for a set
of pending I/O requests. Some of the important disk scheduling algorithms are First-Come-First-Served (FCFS),
Shortest Seek Time First (SSTF), SCAN, Circular Scan (C-SCAN) and LOOK. Out of these disk scheduling
algorithms, the simplest and fair is the FCFS which serves the I/O requests based on their arrival. FCFS is
simple and easy to implement but usually it does not provide the efficient service. Here, I am proposing an
approach which can improve the performance of FCFS and reduce the seek time. This approach can be called
Improved First-Come-First-Served (IFCFS). After applying the suggested improvement, it has been found that
the service is fast and seek time has been reduced drastically. This has been proved with the experimental results with some sets of pending I/O requests.
Author (s) Details
Manish Kumar Mishra
Department of Computer Science, University of Gondar, Ethiopia.