message: PSv2/cfit: Add a note in `Model.fit` that batch-level calls are currently unsupported with `ParameterServerStrategy`.
diff: @@ -954,6 +954,10 @@ class Model(base_layer.Layer, version_utils.ModelVersionSelector):
  and need not be passed into `model.fit`.
  `tf.keras.callbacks.ProgbarLogger` is created or not based on
  `verbose` argument to `model.fit`.
  + Callbacks with batch-level calls are currently unsupported with
  + `tf.distribute.experimental.ParameterServerStrategy`, and users are
  + advised to implement epoch-level calls instead with an appropriate
  + `steps_per_epoch` value.
  validation_split: Float between 0 and 1.
  Fraction of the training data to be used as validation data.
  The model will set apart this fraction of the training data,
  