revise some transformer decoding configuration, support relative position…

revise some transformer decoding configuration, support relative position reprasentation training, add transformer_rpr_base

tensor2tensor/models/common_attention.py

@@ -502,7 +502,7 @@ def _generate_relative_positions_embeddings(length, depth,
   with tf.variable_scope(name):
     # libei: relative_positions_matrix shape is (L, L), value range is 0 ~ 2K (total 2K+1)
     relative_positions_matrix = _generate_relative_positions_matrix(
-        length, max_relative_position,cache=cache)
+        length, max_relative_position, cache=cache)
     vocab_size = max_relative_position * 2 + 1
     # Generates embedding for each relative position of dimension depth.
     embeddings_table = tf.get_variable("embeddings", [vocab_size, depth])
@@ -602,7 +602,7 @@ def dot_product_attention_relative(q,
 
     # This calculation only works for self attention.
     # q, k and v must therefore have the same shape.
-    # wq: compatible means same shape
+    # libei: compatible means same shape
     if not cache:
       q.get_shape().assert_is_compatible_with(k.get_shape())
       q.get_shape().assert_is_compatible_with(v.get_shape())
@@ -610,7 +610,7 @@ def dot_product_attention_relative(q,
     # Use separate embeddings suitable for keys and values.
     depth = q.get_shape().as_list()[3]
     length = common_layers.shape_list(q)[2]
-    # wq: relations_keys: (L, L, H), where H is hidden size of head
+    # libei: relations_keys: (L, L, H), where H is hidden size of head
     relations_keys = _generate_relative_positions_embeddings(
         length, depth, max_relative_position, "relative_positions_keys",
         debug_flag=debug_flag+"+rp-key" if debug_flag is not None else None,

tensor2tensor/models/transformer.py

@@ -33,7 +33,7 @@ from tensor2tensor.models import common_hparams
 from tensor2tensor.models import common_layers
 from tensor2tensor.utils import registry
 from tensor2tensor.utils import t2t_model
-from tensor2tensor.utils import beam_search
+from tensor2tensor.utils import beam_search_fast
 from tensorflow.python.util import nest
 
 import tensorflow as tf
@@ -106,7 +106,7 @@ class Transformer(t2t_model.T2TModel):
     return decoder_output
 
 
-  def _beam_decode(self, features, decode_length, beam_size, top_beams, last_position_only, alpha):
+  def _beam_decode_fast(self, features, decode_length, beam_size, top_beams, last_position_only, alpha):
     """Beam search decoding.
 
     Args:
@@ -274,7 +274,7 @@ def fast_decode(encoder_output,
                 beam_size=1,
                 top_beams=1,
                 alpha=1.0,
-                eos_id=beam_search.EOS_ID,
+                eos_id=beam_search_fast.EOS_ID,
                 batch_size=None,
                 force_decode_length=False):
   """Given encoder output and a symbols to logits function, does fast decoding.
@@ -353,7 +353,7 @@ def fast_decode(encoder_output,
 
   if beam_size > 1:  # Beam Search
     initial_ids = tf.zeros([batch_size], dtype=tf.int32)
-    decoded_ids, scores = beam_search.beam_search(
+    decoded_ids, scores = beam_search_fast.beam_search(
         symbols_to_logits_fn,
         initial_ids,
         beam_size,
@@ -410,7 +410,7 @@ def fast_decode(encoder_output,
             tf.TensorShape([None]),
             tf.TensorShape([None, None]),
             tf.TensorShape([None, None]),
-            nest.map_structure(beam_search.get_state_shape_invariants, cache),
+            nest.map_structure(beam_search_fast.get_state_shape_invariants, cache),
             tf.TensorShape([None]),
         ])
     scores = log_prob
@@ -810,12 +810,12 @@ def transformer_base_v2():
 
 
 @registry.register_hparams
-def transformer_base_rpr_dropout1():
-  hparams = transformer_base()
-  hparams.max_relative_length = 16
+def transformer_rpr_base():
+  hparams = transformer_before()
+  hparams.max_relative_length = 20
   hparams.attention_type = "relative_dot_product"
-  hparams.relu_dropout = 0.1
-  hparams.attention_dropout = 0.1
+  # optimal
+  hparams.filter_size = 4096
   return hparams
 
 

tensor2tensor/utils/beam_search_test.py

@@ -21,7 +21,7 @@ from __future__ import print_function
 # Dependency imports
 
 import numpy as np
-from tensor2tensor.utils import beam_search_slow
+from tensor2tensor.utils import beam_search
 
 import tensorflow as tf
 
@@ -40,7 +40,7 @@ class BeamSearchTest(tf.test.TestCase):
       # Just return random logits
       return tf.random_uniform((batch_size * beam_size, vocab_size))
 
-    final_ids, final_probs = beam_search_slow.beam_search(
+    final_ids, final_probs = beam_search.beam_search(
         symbols_to_logits, initial_ids, beam_size, decode_length, vocab_size,
         0.)
 
@@ -60,7 +60,7 @@ class BeamSearchTest(tf.test.TestCase):
     flags = tf.constant([[True, False, False, True],
                          [False, False, False, True]])
 
-    topk_seq, topk_scores, topk_flags = beam_search_slow.compute_topk_scores_and_seq(
+    topk_seq, topk_scores, topk_flags = beam_search.compute_topk_scores_and_seq(
         sequences, scores, scores, flags, beam_size, batch_size)
 
     with self.test_session():
@@ -115,7 +115,7 @@ class BeamSearchTest(tf.test.TestCase):
       logits = tf.to_float(tf.log(probabilities[pos - 1, :]))
       return logits
 
-    final_ids, final_probs = beam_search_slow.beam_search(
+    final_ids, final_probs = beam_search.beam_search(
         symbols_to_logits,
         initial_ids,
         beam_size,
@@ -146,7 +146,7 @@ class BeamSearchTest(tf.test.TestCase):
       logits = tf.to_float(tf.log(probabilities[pos - 1, :]))
       return logits
 
-    final_ids, final_probs = beam_search_slow.beam_search(
+    final_ids, final_probs = beam_search.beam_search(
         symbols_to_logits,
         initial_ids,
         beam_size,
@@ -175,7 +175,7 @@ class BeamSearchTest(tf.test.TestCase):
       logits = tf.to_float(tf.log(probabilities[pos - 1, :]))
       return logits
 
-    final_ids, final_probs = beam_search_slow.beam_search(
+    final_ids, final_probs = beam_search.beam_search(
         symbols_to_logits,
         initial_ids,
         beam_size,
@@ -215,7 +215,7 @@ class BeamSearchTest(tf.test.TestCase):
       logits = tf.to_float(tf.log(probabilities[pos - 1, :]))
       return logits
 
-    final_ids, final_scores = beam_search_slow.beam_search(
+    final_ids, final_scores = beam_search.beam_search(
         symbols_to_logits,
         initial_ids,
         beam_size,
@@ -258,7 +258,7 @@ class BeamSearchTest(tf.test.TestCase):
       return logits
 
     # Disable early stopping
-    final_ids, final_scores = beam_search_slow.beam_search(
+    final_ids, final_scores = beam_search.beam_search(
         symbols_to_logits,
         initial_ids,
         beam_size,

tensor2tensor/utils/t2t_model.py

@@ -26,7 +26,7 @@ import time
 import six
 from six.moves import xrange  # pylint: disable=redefined-builtin
 
-from tensor2tensor.utils import beam_search_slow
+from tensor2tensor.utils import beam_search
 from tensor2tensor.utils import expert_utils as eu
 from tensor2tensor.utils import modality
 from tensor2tensor.utils import registry
@@ -234,9 +234,9 @@ class T2TModel(object):
     vocab_size = target_modality.top_dimensionality
     # Setting decode length to input length + decode_length
     decode_length = tf.shape(features["inputs"])[1] + tf.constant(decode_length)
-    ids, scores = beam_search_slow.beam_search(symbols_to_logits_fn, initial_ids,
-                                               beam_size, decode_length, vocab_size,
-                                               alpha)
+    ids, scores = beam_search.beam_search(symbols_to_logits_fn, initial_ids,
+                                          beam_size, decode_length, vocab_size,
+                                          alpha)
 
     # Set inputs back to the unexpanded inputs to not to confuse the Estimator!
     features["inputs"] = inputs_old