A system for accelerating database transaction processing by controlling data replication includes a first control unit configured to manage a first storage device and at least one second control unit configured to manage a second storage device. The first control unit writes first data to the first storage device and sends the first data to the second control unit responsive to receiving from a host a first write command including the first data. The first control unit writes second data to the first storage device without sending the second data to the second control unit responsive to receiving from the host a second write command. The second control unit writes the first data to the second storage device responsive to receiving the first data. The second control unit writes the second data to the second storage device responsive to receiving from the host a third write command.