An apparatus comprising a processor component to: receive metadata of data organization within a data set; receive indications of which node devices will be storing the data set as multiple data blocks within a data file; and receive, from each node device, a pointer request to a location within the data file for storing a data set portion as a data block. In response to the data set including partitioned data, for each request for a pointer: determine the location within the data file; generate a map data map entry for the data block; generate therein a sub-block count of data sub-blocks within the data block; generate therein a sub-entry for each data sub-block including size and a hashed identifier derived from a partition label; and provide a pointer to the node device. In response to successful storage of all data blocks, store the map data in the data file.