Skip to content
Permalink
Branch: master
Find file Copy path
Find file Copy path
Fetching contributors…
Cannot retrieve contributors at this time
66 lines (45 sloc) 1.76 KB

Using flags in official models

  1. All common flags must be incorporated in the models.

    Common flags (i.e. batch_size, model_dir, etc.) are provided by various flag definition functions, and channeled through official.utils.flags.core. For instance to define common supervised learning parameters one could use the following code:

    from absl import app as absl_app
    from absl import flags
    
    from official.utils.flags import core as flags_core
    
    
    def define_flags():
      flags_core.define_base()
      flags.adopt_key_flags(flags_core)
    
    
    def main(_):
      flags_obj = flags.FLAGS
      print(flags_obj)
    
    
    if __name__ == "__main__"
      absl_app.run(main)
    
  2. Validate flag values.

    See the Validators section for implementation details.

    Validators in the official model repo should not access the file system, such as verifying that files exist, due to the strict ordering requirements.

  3. Flag values should not be mutated.

    Instead of mutating flag values, use getter functions to return the desired values. An example getter function is get_loss_scale function below:

    # Map string to (TensorFlow dtype, default loss scale)
    DTYPE_MAP = {
        "fp16": (tf.float16, 128),
        "fp32": (tf.float32, 1),
    }
    
    
    def get_loss_scale(flags_obj):
      if flags_obj.loss_scale == "dynamic":
        return flags_obj.loss_scale
      if flags_obj.loss_scale is not None:
        return flags_obj.loss_scale
      return DTYPE_MAP[flags_obj.dtype][1]
    
    
    def main(_):
      flags_obj = flags.FLAGS()
    
      # Do not mutate flags_obj
      # if flags_obj.loss_scale is None:
      #   flags_obj.loss_scale = DTYPE_MAP[flags_obj.dtype][1] # Don't do this
    
      print(get_loss_scale(flags_obj))
      ...
    
You can’t perform that action at this time.