init

vllm/executor/ray_utils.py

@@ -0,0 +1,119 @@
+import pickle
+from typing import List, Optional, Tuple
+
+from vllm.config import ParallelConfig
+from vllm.logger import init_logger
+from vllm.utils import get_ip, is_hip
+from vllm.worker.worker_base import WorkerWrapperBase
+
+logger = init_logger(__name__)
+
+try:
+    import ray
+
+    class RayWorkerWrapper(WorkerWrapperBase):
+        """Ray wrapper for vllm.worker.Worker, allowing Worker to be
+        lazliy initialized after Ray sets CUDA_VISIBLE_DEVICES."""
+
+        def __init__(self, *args, **kwargs) -> None:
+            super().__init__(*args, **kwargs)
+            # Since the compiled DAG runs a main execution
+            # in a different thread that calls cuda.set_device.
+            # The flag indicates is set_device is called on
+            # that thread.
+            self.compiled_dag_cuda_device_set = False
+
+        def get_node_ip(self) -> str:
+            return get_ip()
+
+        def get_node_and_gpu_ids(self) -> Tuple[str, List[int]]:
+            node_id = ray.get_runtime_context().get_node_id()
+            gpu_ids = ray.get_gpu_ids()
+            return node_id, gpu_ids
+
+        def execute_model_compiled_dag_remote(self, ignored):
+            """Used only when compiled DAG is enabled."""
+            import torch
+            if not self.compiled_dag_cuda_device_set:
+                torch.musa.set_device(self.worker.device)
+                self.compiled_dag_cuda_device_set = True
+
+            output = self.worker.execute_model()
+            output = pickle.dumps(output)
+            return output
+
+except ImportError as e:
+    logger.warning(
+        "Failed to import Ray with %r. For distributed inference, "
+        "please install Ray with `pip install ray`.", e)
+    ray = None  # type: ignore
+    RayWorkerWrapper = None  # type: ignore
+
+
+def initialize_ray_cluster(
+    parallel_config: ParallelConfig,
+    ray_address: Optional[str] = None,
+):
+    """Initialize the distributed cluster with Ray.
+
+    it will connect to the Ray cluster and create a placement group
+    for the workers, which includes the specification of the resources
+    for each distributed worker.
+
+    Args:
+        parallel_config: The configurations for parallel execution.
+        ray_address: The address of the Ray cluster. If None, uses
+            the default Ray cluster address.
+    """
+    if ray is None:
+        raise ImportError(
+            "Ray is not installed. Please install Ray to use distributed "
+            "serving.")
+
+    # Connect to a ray cluster.
+    if is_hip():
+        ray.init(address=ray_address,
+                 ignore_reinit_error=True,
+                 num_gpus=parallel_config.world_size)
+    else:
+        ray.init(address=ray_address, ignore_reinit_error=True)
+
+    if parallel_config.placement_group:
+        # Placement group is already set.
+        return
+
+    # Create placement group for worker processes
+    current_placement_group = ray.util.get_current_placement_group()
+    if current_placement_group:
+        # We are in a placement group
+        bundles = current_placement_group.bundle_specs
+        # Verify that we can use the placement group.
+        gpu_bundles = 0
+        for bundle in bundles:
+            bundle_gpus = bundle.get("GPU", 0)
+            if bundle_gpus > 1:
+                raise ValueError(
+                    "Placement group bundle cannot have more than 1 GPU.")
+            if bundle_gpus:
+                gpu_bundles += 1
+        if parallel_config.world_size > gpu_bundles:
+            raise ValueError(
+                "The number of required GPUs exceeds the total number of "
+                "available GPUs in the placement group.")
+    else:
+        num_gpus_in_cluster = ray.cluster_resources().get("GPU", 0)
+        if parallel_config.world_size > num_gpus_in_cluster:
+            raise ValueError(
+                "The number of required GPUs exceeds the total number of "
+                "available GPUs in the cluster.")
+        # Create a new placement group
+        placement_group_specs = ([{"GPU": 1}] * parallel_config.world_size)
+        current_placement_group = ray.util.placement_group(
+            placement_group_specs)
+        # Wait until PG is ready - this will block until all
+        # requested resources are available, and will timeout
+        # if they cannot be provisioned.
+        ray.get(current_placement_group.ready(), timeout=1800)
+
+    # Set the placement group in the parallel config
+    parallel_config.placement_group = current_placement_group