 Practical performance of interpolation search depends on whether the reduced number of probes is outweighed by the more complicated calculations needed for each probe.It can be useful for locating a record in a large sorted file on disk, where each probe involves a disk seek and is much slower than the interpolation arithmetic.Index structures like B-trees also reduce the number of disk accesses, and are more often used to index on-disk data in part because they can index many types of data and can be updated online.