def estimator(self, vocabulary, init_checkpoint=None):
return utils.get_estimator(
model_type=self._model_type,
input_vocab_size=utils.inputs_vocabulary(vocabulary).vocab_size,
output_vocab_size=utils.targets_vocabulary(vocabulary).vocab_size,
layout_rules=self._layout_rules,
mesh_shape=self._mesh_shape,
model_dir=self._model_dir,
batch_size=self.batch_size,
sequence_length=self._sequence_length,
autostack=self._autostack,
learning_rate_schedule=self._learning_rate_schedule,
keep_checkpoint_max=self._keep_checkpoint_max,
save_checkpoints_steps=self._save_checkpoints_steps,
optimizer=self._optimizer,
predict_fn=self._predict_fn,
variable_filter=self._variable_filter,
ensemble_inputs=self._ensemble_inputs,
use_tpu=self._tpu,
tpu_job_name=self._tpu_job_name,
iterations_per_loop=self._iterations_per_loop,
cluster=self._cluster,
init_checkpoint=init_checkpoint)
def __init__(
self,
model_dir,
tpu,
tpu_job_name,
tpu_zone,
gcp_project,
batch_size=("tokens_per_batch", 1024),
sequence_length=None,
vocabulary=None,
model_type="bitransformer",
layout_rules="ensemble:ensemble,batch:batch,d_ff:model,heads:model,vocab:model,experts:batch",
mesh_shape=None,
autostack=True,
learning_rate_schedule=None,
keep_checkpoint_max=None,
save_checkpoints_steps=5000,
optimizer=None,
predict_fn=None,
variable_filter=None,
ensemble_inputs=None,
iterations_per_loop=100,
init_checkpoint=None):
"""Constructor for MtfModel class.
Args:
model_dir: a string, directory to save the model.
tpu: string, the Cloud TPU to use for training.
tpu_job_name: string, name of the TPU worker binary.
tpu_zone: string, GCE zone where the Cloud TPU is located
gcp_project: string, project name for the Cloud TPU-enabled project.
batch_size: An integer or a (method, value) pair to pass to
compute_batch_size(). Note that this is the global batch size and not
the per-shard batch size.
sequence_length: an integer or a dict from feature-key to integer
the (packed) sequence length, e.g. {"inputs": 512, "targets": 128}
vocabulary: a vocabulary.Vocabulary or (inputs_vocabulary,
targets_vocabulary) tuple.
model_type: string, a model type from mesh tf models.
layout_rules: an input to mtf.convert_to_layout_rules()
mesh_shape: a function that returns mtf.shape
autostack: boolean, internally combine variables.
learning_rate_schedule: an optional function taking the scalar name
argument `step` and the numeric argument `total_train_steps` and return
the scalar learning rate.
keep_checkpoint_max: an integer, maximum number of checkpoints to keep.
save_checkpoints_steps: an integer, steps per checkpoint.
optimizer: a class extending optimize.Optimizer, required for training.
predict_fn: an optional function that can be used to override the default
transformer prediction behavior. Must return a tensor of shape
[batch_dim, length_dim] that will be the prediction for each example.
Must accept the following arguments:
- model: a Unitransformer or Bitransformer
- features: a dict representing an example. Every value will be an
mtf.Tensor with shape [batch_dim, length_dim].
- variable_dtype: an mtf.VariableDType
variable_filter: a string, a variable will only be trained if its name
matches this regex. If None (default), train all trainable variables.
ensemble_inputs: an integer, see `train_model` docstring for details.
iterations_per_loop: integer, steps per train loop
init_checkpoint: a string, if not None the read in varialbes from this
checkpoint path when initializing variables.
"""
mesh_shape = mesh_shape or []
vocabulary = vocabulary or SentencePieceVocabulary()
sequence_length = sequence_length or {"inputs": 512, "targets": 512}
if isinstance(sequence_length, int):
sequence_length = {
"inputs": sequence_length,
"targets": sequence_length
}
if not isinstance(batch_size, int):
self._batch_size = utils.compute_batch_size(
sequence_length, mesh_shape, layout_rules, batch_size)
else:
self._batch_size = batch_size
learning_rate_schedule = (
learning_rate_schedule
or learning_rate_schedules.learning_rate_schedule_noam)
optimizer = optimizer or optimize.AdafactorOptimizer
self._sequence_length = sequence_length
self._vocabulary = vocabulary
self._model_dir = model_dir
self._init_checkpoint = init_checkpoint
self._model_type = model_type
self._ensemble_inputs = ensemble_inputs
cluster = tf.distribute.cluster_resolver.TPUClusterResolver(
tpu if (tpu) else "", zone=tpu_zone, project=gcp_project)
self._estimator = utils.get_estimator(
model_type=model_type,
input_vocab_size=utils.inputs_vocabulary(vocabulary).vocab_size,
output_vocab_size=utils.targets_vocabulary(vocabulary).vocab_size,
layout_rules=mtf.convert_to_layout_rules(layout_rules),
mesh_shape=mtf.convert_to_shape(mesh_shape),
model_dir=model_dir,
batch_size=self._batch_size,
sequence_length=sequence_length,
autostack=autostack,
learning_rate_schedule=learning_rate_schedule,
keep_checkpoint_max=keep_checkpoint_max,
save_checkpoints_steps=save_checkpoints_steps,
optimizer=optimizer,
predict_fn=predict_fn,
variable_filter=variable_filter,
ensemble_inputs=ensemble_inputs,
use_tpu=tpu,
tpu_job_name=tpu_job_name,
iterations_per_loop=iterations_per_loop,
cluster=cluster,
init_checkpoint=init_checkpoint)