Internal change

PiperOrigin-RevId: 403471439

official/modeling/multitask/base_trainer.py

@@ -34,7 +34,8 @@ class MultiTaskBaseTrainer(orbit.StandardTrainer):
                multi_task_model: Union[tf.keras.Model,
                                        base_model.MultiTaskBaseModel],
                optimizer: tf.optimizers.Optimizer,
-               trainer_options=None):
+               trainer_options=None,
+               train_datasets=None):
     self._strategy = tf.distribute.get_strategy()
     self._multi_task = multi_task
     self._multi_task_model = multi_task_model
@@ -55,10 +56,11 @@ class MultiTaskBaseTrainer(orbit.StandardTrainer):
         global_step=self.global_step,
         **checkpoint_items)
 
-    train_datasets = {}
-    for name, task in self.multi_task.tasks.items():
-      train_datasets[name] = orbit.utils.make_distributed_dataset(
-          self.strategy, task.build_inputs, task.task_config.train_data)
+    if train_datasets is None:
+      train_datasets = {}
+      for name, task in self.multi_task.tasks.items():
+        train_datasets[name] = orbit.utils.make_distributed_dataset(
+            self.strategy, task.build_inputs, task.task_config.train_data)
 
     super().__init__(
         train_dataset=train_datasets,

official/modeling/multitask/train_lib.py

@@ -15,7 +15,7 @@
 """Multitask training driver library."""
 # pytype: disable=attribute-error
 import os
-from typing import List, Optional
+from typing import Any, List, Optional, Tuple
 from absl import logging
 import orbit
 import tensorflow as tf
@@ -36,11 +36,16 @@ TRAINERS = {
 }
 
 
-def run_experiment(*, distribution_strategy: tf.distribute.Strategy,
-                   task: multitask.MultiTask,
-                   model: base_model.MultiTaskBaseModel, mode: str,
-                   params: configs.MultiTaskExperimentConfig,
-                   model_dir: str) -> base_model.MultiTaskBaseModel:
+def run_experiment(
+    *,
+    distribution_strategy: tf.distribute.Strategy,
+    task: multitask.MultiTask,
+    model: base_model.MultiTaskBaseModel,
+    mode: str,
+    params: configs.MultiTaskExperimentConfig,
+    model_dir: str,
+    trainer: base_trainer.MultiTaskBaseTrainer = None
+) -> base_model.MultiTaskBaseModel:
   """Runs train/eval configured by the experiment params.
 
   Args:
@@ -51,6 +56,8 @@ def run_experiment(*, distribution_strategy: tf.distribute.Strategy,
       or 'continuous_eval'.
     params: ExperimentConfig instance.
     model_dir: A 'str', a path to store model checkpoints and summaries.
+    trainer: (optional) A multi-task trainer to use. If none is provided, a
+      default one will be created based on `params`.
 
   Returns:
       model: `base_model.MultiTaskBaseModel` instance.
@@ -66,8 +73,9 @@ def run_experiment(*, distribution_strategy: tf.distribute.Strategy,
       sampler = task_sampler.get_task_sampler(params.trainer.task_sampler,
                                               task.task_weights)
       kwargs.update(dict(task_sampler=sampler))
-    trainer = TRAINERS[params.trainer.trainer_type](
-        **kwargs) if is_training else None
+    if trainer is None:
+      trainer = TRAINERS[params.trainer.trainer_type](
+          **kwargs) if is_training else None
     if is_eval:
       eval_steps = task.task_eval_steps
       evaluator = evaluator_lib.MultiTaskEvaluator(
@@ -145,7 +153,7 @@ def run_experiment_with_multitask_eval(
     model_dir: str,
     run_post_eval: bool = False,
     save_summary: bool = True,
-    trainer: Optional[core_lib.Trainer] = None) -> tf.keras.Model:
+    trainer: Optional[core_lib.Trainer] = None) -> Tuple[Any, Any]:
   """Runs train/eval configured by the experiment params.
 
   Args: