Final answer:
The SSTF (Shortest Seek Time First) disk scheduling algorithm selects the disk I/O request closest to the disk arm's current position to minimize movement and seek time.
Step-by-step explanation:
The policy described in the question is referred to as the SSTF (Shortest Seek Time First) disk scheduling algorithm. This policy selects the disk I/O (input/output) request that is closest to the current position of the disk's read/write head, thereby minimizing the movement of the disk arm. The primary goal of this policy is to reduce the seek time, which is the time it takes for the disk arm to move to the track where the data is to be read or written.
The main advantage of the SSTF scheduling algorithm is that it generally provides better performance than a simple FIFO (First In First Out) by reducing the average seek time. However, it can suffer from the issue known as starvation, where less frequently accessed tracks may be neglected if there are always closer requests to service. Additionally, as it prioritizes proximity over order, SSTF is not always the optimal choice for systems where fair access or real-time performance is required.