Refactor system architecture (#109)

cacheflow/server/tokenizer_utils.py

@@ -0,0 +1,21 @@
+from typing import Union
+
+from transformers import (AutoConfig, AutoTokenizer, PreTrainedTokenizer,
+                          PreTrainedTokenizerFast)
+
+_MODEL_TYPES_WITH_SLOW_TOKENIZER = [
+    # LLaMA fast tokenizer has a bug related to protobuf.
+    # See https://github.com/WoosukKwon/cacheflow/issues/80#issue-1698550554
+    "llama",
+]
+
+
+def get_tokenizer(
+    model_name: str,
+    *args,
+    **kwargs,
+) -> Union[PreTrainedTokenizer, PreTrainedTokenizerFast]:
+    config = AutoConfig.from_pretrained(model_name)
+    if config.model_type in _MODEL_TYPES_WITH_SLOW_TOKENIZER:
+        kwargs["use_fast"] = False
+    return AutoTokenizer.from_pretrained(model_name, *args, **kwargs)