1. A grid computing system which performs distributed processing between a plurality of information processing apparatuses connected via a network, wherein the plurality of information processing apparatus include a management node which requests distributed processing of a job, and processing nodes which execute the requested distributed processing and transmit processing results to the management node, and the management node selects processing nodes of which distributed processing is to be requested, which have determined to have substantially the same ability of each other on the basis of processing results of test processing requested.