Log loss tensor summaries after they are reduced on the coordinator.

PiperOrigin-RevId: 377187393

research/object_detection/model_lib_v2.py

@@ -20,11 +20,11 @@ from __future__ import print_function
 
 import copy
 import os
+import pprint
 import time
-import numpy as np
 
+import numpy as np
 import tensorflow.compat.v1 as tf
-import tensorflow.compat.v2 as tf2
 
 from object_detection import eval_util
 from object_detection import inputs
@@ -183,6 +183,22 @@ def _ensure_model_is_built(model, input_dataset, unpad_groundtruth_tensors):
         ))
 
 
+def normalize_dict(values_dict, num_replicas):
+
+  num_replicas = tf.constant(num_replicas, dtype=tf.float32)
+  return {key: tf.math.divide(loss, num_replicas) for key, loss
+          in values_dict.items()}
+
+
+def reduce_dict(strategy, reduction_dict, reduction_op):
+  # TODO(anjalisridhar): explore if it is safe to remove the # num_replicas
+  # scaling of the loss and switch this to a ReduceOp.Mean
+  return {
+      name: strategy.reduce(reduction_op, loss, axis=None)
+      for name, loss in reduction_dict.items()
+  }
+
+
 # TODO(kaftan): Explore removing learning_rate from this method & returning
 ## The full losses dict instead of just total_loss, then doing all summaries
 ## saving in a utility method called by the outer training loop.
@@ -192,10 +208,8 @@ def eager_train_step(detection_model,
                      labels,
                      unpad_groundtruth_tensors,
                      optimizer,
-                     learning_rate,
                      add_regularization_loss=True,
                      clip_gradients_value=None,
-                     global_step=None,
                      num_replicas=1.0):
   """Process a single training batch.
 
@@ -266,16 +280,10 @@ def eager_train_step(detection_model,
           float32 tensor containing the weights of the keypoint depth feature.
     unpad_groundtruth_tensors: A parameter passed to unstack_batch.
     optimizer: The training optimizer that will update the variables.
-    learning_rate: The learning rate tensor for the current training step.
-      This is used only for TensorBoard logging purposes, it does not affect
-       model training.
     add_regularization_loss: Whether or not to include the model's
       regularization loss in the losses dictionary.
     clip_gradients_value: If this is present, clip the gradients global norm
       at this value using `tf.clip_by_global_norm`.
-    global_step: The current training step. Used for TensorBoard logging
-      purposes. This step is not updated by this function and must be
-      incremented separately.
     num_replicas: The number of replicas in the current distribution strategy.
       This is used to scale the total loss so that training in a distribution
       strategy works correctly.
@@ -296,31 +304,18 @@ def eager_train_step(detection_model,
     losses_dict, _ = _compute_losses_and_predictions_dicts(
         detection_model, features, labels, add_regularization_loss)
 
-    total_loss = losses_dict['Loss/total_loss']
-
-    # Normalize loss for num replicas
-    total_loss = tf.math.divide(total_loss,
-                                tf.constant(num_replicas, dtype=tf.float32))
-    losses_dict['Loss/normalized_total_loss'] = total_loss
-
-  for loss_type in losses_dict:
-    tf.compat.v2.summary.scalar(
-        loss_type, losses_dict[loss_type], step=global_step)
+    losses_dict = normalize_dict(losses_dict, num_replicas)
 
   trainable_variables = detection_model.trainable_variables
 
+  total_loss = losses_dict['Loss/total_loss']
   gradients = tape.gradient(total_loss, trainable_variables)
 
   if clip_gradients_value:
     gradients, _ = tf.clip_by_global_norm(gradients, clip_gradients_value)
   optimizer.apply_gradients(zip(gradients, trainable_variables))
-  tf.compat.v2.summary.scalar('learning_rate', learning_rate, step=global_step)
-  tf.compat.v2.summary.image(
-      name='train_input_images',
-      step=global_step,
-      data=features[fields.InputDataFields.image],
-      max_outputs=3)
-  return total_loss
+
+  return losses_dict
 
 
 def validate_tf_v2_checkpoint_restore_map(checkpoint_restore_map):
@@ -479,7 +474,12 @@ def train_loop(
       Checkpoint every n training steps.
     checkpoint_max_to_keep:
       int, the number of most recent checkpoints to keep in the model directory.
-    record_summaries: Boolean, whether or not to record summaries.
+    record_summaries: Boolean, whether or not to record summaries defined by
+      the model or the training pipeline. This does not impact the summaries
+      of the loss values which are always recorded. Examples of summaries
+      that are controlled by this flag include:
+        - Image summaries of training images.
+        - Intermediate tensors which maybe logged by meta architectures.
     performance_summary_exporter: function for exporting performance metrics.
     num_steps_per_iteration: int, The number of training steps to perform
       in each iteration.
@@ -538,7 +538,8 @@ def train_loop(
   strategy = tf.compat.v2.distribute.get_strategy()
   with strategy.scope():
     detection_model = MODEL_BUILD_UTIL_MAP['detection_model_fn_base'](
-        model_config=model_config, is_training=True)
+        model_config=model_config, is_training=True,
+        add_summaries=record_summaries)
 
     def train_dataset_fn(input_context):
       """Callable to create train input."""
@@ -581,11 +582,9 @@ def train_loop(
   # is the chief.
   summary_writer_filepath = get_filepath(strategy,
                                          os.path.join(model_dir, 'train'))
-  if record_summaries:
+
   summary_writer = tf.compat.v2.summary.create_file_writer(
       summary_writer_filepath)
-  else:
-    summary_writer = tf2.summary.create_noop_writer()
 
   with summary_writer.as_default():
     with strategy.scope():
@@ -619,32 +618,37 @@ def train_loop(
 
         def train_step_fn(features, labels):
           """Single train step."""
-          loss = eager_train_step(
+
+          if record_summaries:
+            tf.compat.v2.summary.image(
+                name='train_input_images',
+                step=global_step,
+                data=features[fields.InputDataFields.image],
+                max_outputs=3)
+          losses_dict = eager_train_step(
               detection_model,
               features,
               labels,
               unpad_groundtruth_tensors,
               optimizer,
-              learning_rate=learning_rate_fn(),
               add_regularization_loss=add_regularization_loss,
               clip_gradients_value=clip_gradients_value,
-              global_step=global_step,
               num_replicas=strategy.num_replicas_in_sync)
           global_step.assign_add(1)
-          return loss
+          return losses_dict
 
         def _sample_and_train(strategy, train_step_fn, data_iterator):
           features, labels = data_iterator.next()
           if hasattr(tf.distribute.Strategy, 'run'):
-            per_replica_losses = strategy.run(
+            per_replica_losses_dict = strategy.run(
                 train_step_fn, args=(features, labels))
           else:
-            per_replica_losses = strategy.experimental_run_v2(
-                train_step_fn, args=(features, labels))
-          # TODO(anjalisridhar): explore if it is safe to remove the
-          ## num_replicas scaling of the loss and switch this to a ReduceOp.Mean
-          return strategy.reduce(tf.distribute.ReduceOp.SUM,
-                                 per_replica_losses, axis=None)
+            per_replica_losses_dict = (
+                strategy.experimental_run_v2(
+                    train_step_fn, args=(features, labels)))
+
+          return reduce_dict(
+              strategy, per_replica_losses_dict, tf.distribute.ReduceOp.SUM)
 
         @tf.function
         def _dist_train_step(data_iterator):
@@ -670,7 +674,7 @@ def train_loop(
         for _ in range(global_step.value(), train_steps,
                        num_steps_per_iteration):
 
-          loss = _dist_train_step(train_input_iter)
+          losses_dict = _dist_train_step(train_input_iter)
 
           time_taken = time.time() - last_step_time
           last_step_time = time.time()
@@ -681,11 +685,19 @@ def train_loop(
 
           steps_per_sec_list.append(steps_per_sec)
 
+          logged_dict = losses_dict.copy()
+          logged_dict['learning_rate'] = learning_rate_fn()
+
+          for key, val in logged_dict.items():
+            tf.compat.v2.summary.scalar(key, val, step=global_step)
+
           if global_step.value() - logged_step >= 100:
+            logged_dict_np = {name: value.numpy() for name, value in
+                              logged_dict.items()}
             tf.logging.info(
-                'Step {} per-step time {:.3f}s loss={:.3f}'.format(
-                    global_step.value(), time_taken / num_steps_per_iteration,
-                    loss))
+                'Step {} per-step time {:.3f}s'.format(
+                    global_step.value(), time_taken / num_steps_per_iteration))
+            tf.logging.info(pprint.pformat(logged_dict_np, width=40))
             logged_step = global_step.value()
 
           if ((int(global_step.value()) - checkpointed_step) >=
@@ -704,7 +716,7 @@ def train_loop(
         'steps_per_sec': np.mean(steps_per_sec_list),
         'steps_per_sec_p50': np.median(steps_per_sec_list),
         'steps_per_sec_max': max(steps_per_sec_list),
-        'last_batch_loss': float(loss)
+        'last_batch_loss': float(losses_dict['Loss/total_loss'])
     }
     mixed_precision = 'bf16' if kwargs['use_bfloat16'] else 'fp32'
     performance_summary_exporter(metrics, mixed_precision)

research/object_detection/model_main_tf2.py

@@ -65,8 +65,10 @@ flags.DEFINE_integer(
 flags.DEFINE_integer(
     'checkpoint_every_n', 1000, 'Integer defining how often we checkpoint.')
 flags.DEFINE_boolean('record_summaries', True,
-                     ('Whether or not to record summaries during'
-                      ' training.'))
+                     ('Whether or not to record summaries defined by the model'
+                      ' or the training pipeline. This does not impact the'
+                      ' summaries of the loss values which are always'
+                      ' recorded.'))
 
 FLAGS = flags.FLAGS