PARALLEL PROCESSING APPARATUS AND COMPUTER-READABLE RECORDING MEDIUM STORING PARALLEL PROCESSING PROGRAM

A parallel processing apparatus comprises a plurality of arithmetic processors and a plurality of storages. A first processor executes first processing included in parallel processing by using first unit of processing, a second processor executes second processing by using second unit of processing, a first storage stores first information and a second storage stores second information, each to be used by the first and the second processors in an aggregate operation, the first information contains first parent information indicating that the second unit of processing is a parent of the first unit of processing, the second information contains first child information indicating that the first unit of processing is a child of the second unit of processing, and the first processor transmits an end notification to the second processor when the first processing is ended and the first information does not contain information indicating a child of the first unit.