Determining an allocation configuration for allocating virtual machines to physical machines

An information processing system having a plurality of physical machines that each provide a virtual-machine operating environment and an information processing apparatus that allocates virtual machines to the plurality of physical machines, the information processing apparatus comprising:

• a prediction section configured to determine a total predicted peak usage amount of physical resources based on the sum of predicted peak usage amounts for each time interval of a plurality of time intervals for individual clusters of a plurality of clusters wherein the clusters include a plurality of virtual machines;
• a setting section configured to set a constraint that ensures that, for individual combinations of a first physical machine, a second physical machine, and a time interval t, the total predicted peak usage amount of the physical resource predicted for the first physical machine if the second physical machine stops during the time interval t does not exceed a physical resource amount prepared for the first physical machine,
• wherein for the first physical machine k, the second physical machine k′, and the time interval t, for which the total predicted peak usage amount is predicted,
• the setting section formulates the total predicted peak usage amount φk,k′,t as a sum total of the predicted peak usage amount γc,t of clusters c, predicted for the first physical machine k if the second physical machine k′ stops, the predicted peak usage amount γc,t being given in correspondence with a decision variable that defines the allocation configuration of the clusters c, and the predicted peak usage is determined for each resource and time interval;
• an allocation-configuration deriving section configured to derive an allocation configuration by calculating, in accordance with the constraint, a solution to an optimization problem for minimizing, as an objective function, the sum total of the physical resource amounts of the plurality of physical machines to which the virtual machines are allocated;
• and
• an allocation processing section configured to allocate the virtual machines on the physical machine, of the plurality of physical machines, determined according to the allocation configuration.