Adds parallel model weight loading for runai_streamer (#21330)

Signed-off-by: bbartels <benjamin@bartels.dev>
Co-authored-by: Cyrus Leung <cyrus.tl.leung@gmail.com>

setup.py

@@ -659,7 +659,8 @@ setup(
         "bench": ["pandas", "datasets"],
         "tensorizer": ["tensorizer==2.10.1"],
         "fastsafetensors": ["fastsafetensors >= 0.1.10"],
-        "runai": ["runai-model-streamer", "runai-model-streamer-s3", "boto3"],
+        "runai":
+        ["runai-model-streamer >= 0.13.3", "runai-model-streamer-s3", "boto3"],
         "audio": ["librosa", "soundfile",
                   "mistral_common[audio]"],  # Required for audio processing
         "video": []  # Kept for backwards compatibility

vllm/model_executor/model_loader/weight_utils.py

@@ -482,14 +482,20 @@ def runai_safetensors_weights_iterator(
 ) -> Generator[tuple[str, torch.Tensor], None, None]:
     """Iterate over the weights in the model safetensor files."""
     with SafetensorsStreamer() as streamer:
-        for st_file in tqdm(
-                hf_weights_files,
+        streamer.stream_files(hf_weights_files)
+        total_tensors = sum(
+            len(tensors_meta)
+            for tensors_meta in streamer.files_to_tensors_metadata.values())
+
+        tensor_iter = tqdm(
+            streamer.get_tensors(),
+            total=total_tensors,
             desc="Loading safetensors using Runai Model Streamer",
-                disable=not enable_tqdm(use_tqdm_on_load),
             bar_format=_BAR_FORMAT,
-        ):
-            streamer.stream_file(st_file)
-            yield from streamer.get_tensors()
+            disable=not enable_tqdm(use_tqdm_on_load),
+        )
+
+        yield from tensor_iter
 
 
 def fastsafetensors_weights_iterator(