def METHOD_NAME(self, params):
    max_cuda_used_pre_op = self.mem_monitor.finish()
    # record max cuda overall data for prev OP.
    self._memstats.record_max_cuda_overall_data(max_cuda_used_pre_op)
    # record max cuda non model data for prev OP.
    self._memstats.calc_max_cuda_non_model_data()
    self._allocate_params_on_cuda(params)
    # record max cuda  model data for current OP
    self.record_model_data_volume(params)
    self.mem_monitor.start()
    self._memstats.increase_preop_step(params)