1. A computer program product for merging metadata for a plurality of storage regions within memory, wherein the metadata for each storage region comprises an interval including first and second interval values indicating a value range for values within that storage region, the computer program product comprising: a computer readable storage medium having computer readable program code embodied therewith, the computer readable program code comprising computer readable program code configured to: examine the first and second interval values to identify overlapping storage regions and to produce a sum of overlapped storage regions, wherein examining the first and second interval values includes: determining for each examined interval value a difference in quantity between examined first interval values and examined second interval values; and accumulating the differences in quantity for the examined interval values to produce the sum of overlapped storage regions; and compare the sum of overlapped storage regions to a threshold and merge the metadata of the overlapped storage regions based on the comparison.