To perform a sort operation on a spreadsheet table, data items in the spreadsheet table are divided into a plurality of blocks. Multiple threads are then used to sort the data items in the blocks. After the data items in the blocks are sorted, multiple threads are used to merge the blocks into a final block. The final block contains each of the data items in the spreadsheet table. A sorted version of the spreadsheet table is then displayed. Data items in the sorted version of the spreadsheet table have the same order as an order of data items in the final block.