Fix vllm:prompt_tokens_total metric calculation (#2869)

tests/conftest.py

@@ -13,12 +13,10 @@ _TEST_PROMPTS = [os.path.join(_TEST_DIR, "prompts", "example.txt")]
 _LONG_PROMPTS = [os.path.join(_TEST_DIR, "prompts", "summary.txt")]
 
 
-def _read_prompts(filename: str) -> str:
-    prompts = []
+def _read_prompts(filename: str) -> List[str]:
     with open(filename, "r") as f:
-        prompt = f.readline()
-        prompts.append(prompt)
-    return prompts
+        prompts = f.readlines()
+        return prompts
 
 
 @pytest.fixture
@@ -165,6 +163,7 @@ class VllmRunner:
         model_name: str,
         tokenizer_name: Optional[str] = None,
         dtype: str = "half",
+        disable_log_stats: bool = True,
         tensor_parallel_size: int = 1,
     ) -> None:
         self.model = LLM(
@@ -173,6 +172,7 @@ class VllmRunner:
             trust_remote_code=True,
             dtype=dtype,
             swap_space=0,
+            disable_log_stats=disable_log_stats,
             tensor_parallel_size=tensor_parallel_size,
         )