Provided are a method, system, and article of manufacture, wherein a data structure corresponding to a set of client nodes selected from a plurality of client nodes is generated. Objects from the selected set of client nodes are stored in the data structure. A determination is made that an object corresponding to a client node of the selected set of client nodes has to be stored. An additional determination is made as to whether the object has already been stored in the data structure by any client node of the selected set of client nodes. The object is stored in the data structure, in response to determining that the object has not already been stored in the data structure by any client node of the selected set of client nodes.