Consider a disk drive with 16 surfaces, 512 tracks / surface, 256 sectors / track, 8 KB / sector with a rotation speed of 3600 rpm. The disk is operated in cycle stealing mode where by whenever 1 B word is ready it is sent to memory, similarly. For writing, the disk interface reads a 4 B word from the memory in each DMA cycle. The time for each memory cycle is 50 nsec. The maximum percentage of time that the CPU gets blocked during DMA operation is __________ .
