feat(server): batch tokenization for flash causal lm (#411)

server/text_generation_server/models/flash_causal_lm.py

@@ -79,6 +79,16 @@ class FlashCausalLMBatch(Batch):
         dtype: torch.dtype,
         device: torch.device,
     ) -> "FlashCausalLMBatch":
+        batch_inputs = []
+        max_truncation = 0
+        for r in pb.requests:
+            batch_inputs.append(r.inputs)
+            max_truncation = max(max_truncation, r.truncate)
+
+        batch_tokenized_inputs = tokenizer(
+            batch_inputs, truncation=True, max_length=max_truncation
+        )["input_ids"]
+
         position_ids = []
         cu_seqlens = [0]
         max_seqlen = 0
@@ -106,13 +116,13 @@ class FlashCausalLMBatch(Batch):
         max_length = 0
 
         # Parse batch
-        for i, r in enumerate(pb.requests):
+        for i, (r, tokenized_input) in enumerate(
+            zip(pb.requests, batch_tokenized_inputs)
+        ):
             # request id -> idx in list mapping
             requests_idx_mapping[r.id] = i
 
-            tokenized_input = tokenizer(
-                r.inputs, truncation=True, max_length=r.truncate
-            )["input_ids"]
+            tokenized_input = tokenized_input[-r.truncate :]
 
             input_length = len(tokenized_input)
             max_seqlen = max(max_seqlen, input_length)

server/text_generation_server/utils/hub.py

@@ -134,7 +134,7 @@ def download_weights(
 ) -> List[Path]:
     """Download the safetensors files from the hub"""
 
-    def download_file(filename, tries=5):
+    def download_file(filename, tries=5, backoff: int = 5):
         local_file = try_to_load_from_cache(model_id, revision, filename)
         if local_file is not None:
             logger.info(f"File {filename} already present in cache.")
@@ -158,6 +158,8 @@ def download_weights(
                 if i + 1 == tries:
                     raise e
                 logger.error(e)
+                logger.info(f"Retrying in {backoff} seconds")
+                time.sleep(backoff)
                 logger.info(f"Retry {i + 1}/{tries - 1}")
 
     # We do this instead of using tqdm because we want to parse the logs with the launcher