A data management device (10) is provided, comprising a control module (100) and a storage module (1 10), wherein the storage module (1 10) is configured to store a plurality of data sets in a plurality of data set groups such that the plurality of data sets is assigned to the plurality of data set groups such that every data set group comprises at least one data set and every data set is stored in one data set group only and wherein the control module (100) is configured to assign an exclusive execution context to each data set group and to estimate a number of data set requests for every data set. The control module (100) is further configured to determine data sets for every data set group based on the estimated number of data set requests and to reassign the data sets to the data set groups such that the estimated number of data set requests in a data set group is less or equal to a predetermined number of data set requests for at least one exclusive execution context which is assigned to one of the plurality of data set groups. Thus, skew workload of the data set groups and the assigned exclusive execution contexts can be avoided.