fix(server): T5 weights names. (#582)

Fixes #541

server/text_generation_server/models/custom_modeling/t5_modeling.py

@@ -1006,12 +1006,7 @@ class T5ForConditionalGeneration(T5PreTrainedModel):
         super().__init__(config)
         self.model_dim = config.d_model
 
-        try:
-            self.shared = TensorParallelEmbedding(prefix="shared", weights=weights)
-        except RuntimeError:
-            self.shared = TensorParallelEmbedding(
-                prefix="encoder.embed_tokens", weights=weights
-            )
+        self.shared = TensorParallelEmbedding(prefix="shared", weights=weights)
 
         encoder_config = copy.deepcopy(config)
         encoder_config.is_decoder = False

server/text_generation_server/models/t5.py

@@ -55,7 +55,16 @@ class T5Sharded(Seq2SeqLM):
         torch.distributed.barrier(group=self.process_group)
         filenames = weight_files(model_id, revision=revision, extension=".safetensors")
         weights = Weights(
-            filenames, device=device, dtype=dtype, process_group=self.process_group
+            filenames,
+            device=device,
+            dtype=dtype,
+            process_group=self.process_group,
+            aliases={
+                "shared.weight": [
+                    "encoder.embed_tokens.weight",
+                    "decoder.embed_tokens.weight",
+                ]
+            },
         )
 
         model = T5ForConditionalGeneration(config, weights)