Cached Magneto-optic Storage

Magneto-Optic (MO) disk drives often display performance inferior to their magnetic counterparts, due to the high mass head/positioner and two pass write operation associated with MO. This paper will examine the effect of adding cache to an MO disk drive, and compare the result to a non-cached magnetic disk drive with equivalent capacity. First, traces of 130 000 disk requests under the popular Windows environment are collected. Second, the performance of MO and magnetic storage devices are characterized in a seek profile. Third, a trace driven simulation model is constructed to measure the effectiveness of 64KB to 8MB caches located in the disk drive controller. Finally, conclusions are drawn regarding the relationship between cache size and access time in the Windows environment.