Add more generator at first_stage_anchor_generator

[chuongloc]

my model's performance seem to be quite lacking in Loss/RPNLoss/objectness_loss so i did add one more grid_anchor_generator to first_stage_anchor_generator

first_stage_anchor_generator {
      grid_anchor_generator {
        scales: [0.25, 0.5, 1.0, 2.0]
        aspect_ratios: [0.25, 0.5, 1.0]
        height_stride: 16
        width_stride: 16
      }
      grid_anchor_generator {
        scales: [0.25, 0.5, 1.0, 2.0]
        aspect_ratios: [1.5, 2.0, 3.0]
        height_stride: 8
        width_stride: 8
      }
    }

Is my model have 2 anchor generator or 1? Can this way improve my model?