make attn dropout 0.1 default for big en-de transformer

fairseq/models/transformer.py

@@ -423,8 +423,9 @@ def transformer_wmt_en_de(args):
     args.decoder_attention_heads = 8
 
 
-@register_model_architecture('transformer', 'transformer_wmt_en_de_big')
-def transformer_wmt_en_de_big(args):
+# parameters used in the "Attention Is All You Need" paper (Vaswani, et al, 2017)
+@register_model_architecture('transformer', 'transformer_vaswani_wmt_en_de_big')
+def transformer_vaswani_wmt_en_de_big(args):
     base_architecture(args)
     args.encoder_embed_dim = 1024
     args.encoder_ffn_embed_dim = 4096
@@ -436,18 +437,17 @@ def transformer_wmt_en_de_big(args):
     args.decoder_attention_heads = 16
 
 
+@register_model_architecture('transformer', 'transformer_wmt_en_de_big')
+def transformer_wmt_en_de_big(args):
+    transformer_vaswani_wmt_en_de_big(args)
+    args.attention_dropout = 0.1
+
+
+# default parameters used in tensor2tensor implementation
 @register_model_architecture('transformer', 'transformer_wmt_en_de_big_t2t')
 def transformer_wmt_en_de_big_t2t(args):
-    base_architecture(args)
-    args.encoder_embed_dim = 1024
-    args.encoder_ffn_embed_dim = 4096
-    args.encoder_layers = 6
-    args.encoder_attention_heads = 16
+    transformer_vaswani_wmt_en_de_big(args)
     args.encoder_normalize_before = True
-    args.decoder_embed_dim = 1024
-    args.decoder_ffn_embed_dim = 4096
-    args.decoder_layers = 6
-    args.decoder_attention_heads = 16
     args.decoder_normalize_before = True
     args.attention_dropout = 0.1
     args.relu_dropout = 0.1