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Both RAID-0 and RAID-1 require the synchronization of disk drive heads. Seek time of a disk drive is the time it takes for the read/write head to position itself over the right track on the disk, and for the disk to spin to the position of the data. If disks are of different speeds, then seek time in an array will be lowered to that of the slowest drive. Seek time is important for applications that require reading and writing to many random locations, such as file servers. Neither RAID-0 nor RAID-1 have any effect on seek time. Seek time can be improved by faster spinning disks or disks with greater data density.

Another aspect of drive performance is sustained transfer rate. This is the amount of contiguous data that can be read or written over a certain period of time. Since it is usually determined for large blocks of data, it indicates performance for applications that manipulate large data files, such as image and video files. Striping can multiply sustained transfer rate by the number of drives in the striped array, whereas mirroring has no effect on transfer rate. Windows XP has a feature called disk optimization and application/boot prefetching, which also benefits significantly from striping. This feature basically reorganizes the files into larger, contiguous blocks, speeding up bootup and program startup. Of course, there are more aspects to performance than just these basic ones.