Disk rotation latency is becoming an increasingly significant component of disk service time, and yet has rarely been exposed to system software for scheduling purpose. In this paper, we presented the design and implementation of a disk scheduler that can effectively incorporate rotation latency into its scheduling decision. The two enabling mechanisms responsible for the successful implementation of this disk scheduler are an accurate run-time disk head position prediction scheme, and a precise disk service time model. We show that the accuracy of disk head position prediction and disk service time prediction can approach close to 100% and more than 95%, respectively. We used both real and synthetic traces to evaluate the performance of this rotation latency-sensitive disk scheduler (RSDS) and its variants, and found that the performance improvement of RSDS over conventional disk schedulers that consider only seek delay is up to 48%.