Information processing system, information processing apparatus, load balancing methods, planning methods for database deployment and program for performing the connection distribution for load balancing in a distributed database

The present invention is load balancing between physical nodes through in a distributed database environment. An information processing system 100 of the present invention includes a plurality of database servers 122, which are provided distributed on a plurality of physical nodes, whereby two or more servers of the plurality of database servers that are responsible for mutually different data on one and the same physical nodes are provided and one or more servers that are responsible for the same data as one of the two or more servers on one or more other physical nodes are provided; and a distribution area (140, 170) for distributing connections by monitoring the load on each of the physical nodes and displacing a connection to a client from a database server on a physical node with a working load that exceeds a target value to a database server on a physical node with a working load, which is less than the target value, so that the compounds are distributed so that they balance the workload.