Q25

A hard disk is connected to a $50$ MHz processor through a DMA controller. Assume that the initial set-up of a DMA transfer takes $1000$ clock cycles for the processor, and assume that the handling of the interrupt at DMA completion requires $500$ clock cycles for the processor. The hard disk has a transfer rate of $2000$ Kbytes/sec and average block transferred is $4$ K bytes. What fraction of the processor time is consumed by the disk, if the disk is actively transferring $100\%$ of the time?