1. A processing device, comprising: a transaction input/output CPU for receiving a transaction to be executed and outputting an execution result of the transaction; a plurality of processing CPUs for executing the transaction according to an instruction from the transaction input/output CPU; a plurality of transaction storage units provided in relation to each processing CPU, for storing the transaction inputted to the transaction input/output CPU and an execution result of the transaction; and a destination storage unit for storing storage destination information indicating a storage destination common to the plurality of storage units, wherein the processing CPU reads the storage destination information from the destination storage unit and reads the transaction from the storage destination of the transaction stored in the transaction storage unit related to each processing CPU and executes the transaction.