Various embodiments for adaptive reorganization of a virtual storage access method (VSAM) data set are provided. In one exemplary embodiment, upon each control interval (CI) split of a plurality of CI splits occurring over a period of time, historical data including a key value for a record causing each CI split is recorded in a data repository. The historical data is analyzed with a predictive algorithm to determine an amount of free space to be allocated to each of a plurality of control intervals generated pursuant to the adaptive reorganization. The predictive algorithm allocates a greater percentage of the free space to a first location of the VVDS having a larger proportion of historically placed key values than a second location of the VVDS having a smaller proportion of the historically placed key values.