1. A method for generating a tree map, the method comprising: obtaining, by a processing device, node information relating to a plurality of nodes to be processed, the plurality of nodes being sub-nodes sharing a same parent node and the node information comprising at least a respective size of each of the plurality of nodes; identifying, among the plurality of nodes, a plurality of candidate nodes, where the respective node size of each candidate node is less than a threshold size; determining, based at least in part on the node information, a size of a display screen, and the threshold size, a super node that includes the plurality of candidate nodes, wherein displaying the super node in a zooming-in mode on the display screen causes at least one of the plurality of candidate nodes to be displayed at a respective display size not less than the threshold size; and determining data required for displaying the tree map based at least in part on the super node.