def _get_squad_model():
"""Get Squad model and optimizer."""
squad_model, core_model = bert_models.squad_model(
bert_config,
max_seq_length,
float_type=tf.float16 if use_float16 else tf.float32)
squad_model.optimizer = optimization.create_optimizer(
FLAGS.learning_rate, steps_per_epoch * epochs, warmup_steps)
if use_float16:
# Wraps optimizer with a LossScaleOptimizer. This is done automatically
# in compile() with the "mixed_float16" policy, but since we do not call
# compile(), we must wrap the optimizer manually.
squad_model.optimizer = (
tf.keras.mixed_precision.experimental.LossScaleOptimizer(
squad_model.optimizer,
loss_scale=common_flags.get_loss_scale()))
if FLAGS.fp16_implementation == 'graph_rewrite':
# Note: when flags_obj.fp16_implementation == "graph_rewrite", dtype as
# determined by flags_core.get_tf_dtype(flags_obj) would be 'float32'
# which will ensure tf.compat.v2.keras.mixed_precision and
# tf.train.experimental.enable_mixed_precision_graph_rewrite do not double
# up.
squad_model.optimizer = tf.train.experimental.enable_mixed_precision_graph_rewrite(
squad_model.optimizer)
return squad_model, core_model
def predict_squad_customized(strategy, input_meta_data, bert_config,
predict_tfrecord_path, num_steps):
"""Make predictions using a Bert-based squad model."""
primary_cpu_task = '/job:worker' if FLAGS.tpu else ''
with tf.device(primary_cpu_task):
predict_dataset = input_pipeline.create_squad_dataset(
predict_tfrecord_path,
input_meta_data['max_seq_length'],
FLAGS.predict_batch_size,
is_training=False)
predict_iterator = iter(
strategy.experimental_distribute_dataset(predict_dataset))
with strategy.scope():
# Prediction always uses float32, even if training uses mixed precision.
tf.keras.mixed_precision.experimental.set_policy('float32')
squad_model, _ = bert_models.squad_model(
bert_config,
input_meta_data['max_seq_length'],
float_type=tf.float32)
checkpoint_path = tf.train.latest_checkpoint(FLAGS.model_dir)
logging.info('Restoring checkpoints from %s', checkpoint_path)
checkpoint = tf.train.Checkpoint(model=squad_model)
checkpoint.restore(checkpoint_path).expect_partial()
@tf.function
def predict_step(iterator):
"""Predicts on distributed devices."""
def _replicated_step(inputs):
"""Replicated prediction calculation."""
x, _ = inputs
unique_ids, start_logits, end_logits = squad_model(
x, training=False)
return dict(unique_ids=unique_ids,
start_logits=start_logits,
end_logits=end_logits)
outputs = strategy.experimental_run_v2(_replicated_step,
args=(next(iterator), ))
return tf.nest.map_structure(strategy.experimental_local_results,
outputs)
all_results = []
for _ in range(num_steps):
predictions = predict_step(predict_iterator)
for result in get_raw_results(predictions):
all_results.append(result)
if len(all_results) % 100 == 0:
logging.info('Made predictions for %d records.',
len(all_results))
return all_results
def _get_squad_model():
"""Get Squad model and optimizer."""
squad_model, core_model = bert_models.squad_model(
bert_config,
max_seq_length,
float_type=tf.float16 if use_float16 else tf.float32)
squad_model.optimizer = optimization.create_optimizer(
FLAGS.learning_rate, steps_per_epoch * epochs, warmup_steps)
if use_float16:
squad_model.optimizer = (
tf.keras.mixed_precision.experimental.LossScaleOptimizer(
squad_model.optimizer,
loss_scale=common_flags.get_loss_scale()))
return squad_model, core_model
def _get_squad_model():
"""Get Squad model and optimizer."""
squad_model, core_model = bert_models.squad_model(
bert_config,
max_seq_length,
float_type=tf.float16 if use_float16 else tf.float32)
squad_model.optimizer = optimization.create_optimizer(
FLAGS.learning_rate, steps_per_epoch * epochs, warmup_steps)
if use_float16:
# Wraps optimizer with a LossScaleOptimizer. This is done automatically
# in compile() with the "mixed_float16" policy, but since we do not call
# compile(), we must wrap the optimizer manually.
squad_model.optimizer = (
tf.keras.mixed_precision.experimental.LossScaleOptimizer(
squad_model.optimizer, loss_scale=common_flags.get_loss_scale()))
return squad_model, core_model
def export_squad(model_export_path, input_meta_data):
"""Exports a trained model as a `SavedModel` for inference.
Args:
model_export_path: a string specifying the path to the SavedModel directory.
input_meta_data: dictionary containing meta data about input and model.
Raises:
Export path is not specified, got an empty string or None.
"""
if not model_export_path:
raise ValueError('Export path is not specified: %s' % model_export_path)
bert_config = modeling.BertConfig.from_json_file(FLAGS.bert_config_file)
squad_model, _ = bert_models.squad_model(
bert_config, input_meta_data['max_seq_length'], float_type=tf.float32)
model_saving_utils.export_bert_model(
model_export_path, model=squad_model, checkpoint_dir=FLAGS.model_dir)
def _get_squad_model():
squad_model, core_model = bert_models.squad_model(
bert_config, max_seq_length, float_type=tf.float32)
squad_model.optimizer = optimization.create_optimizer(
FLAGS.learning_rate, steps_per_epoch * epochs, warmup_steps)
return squad_model, core_model
