import copy
import json
import logging
import os
import subprocess
import tempfile
import time
from typing import Dict, Optional
import yaml
import ray
import ray._private.services
from ray._private import ray_constants
from ray._private.client_mode_hook import disable_client_hook
from ray._raylet import GcsClientOptions
from ray.autoscaler._private.fake_multi_node.node_provider import FAKE_HEAD_NODE_ID
from ray.util.annotations import DeveloperAPI
logger = logging.getLogger(__name__)
cluster_not_supported = os.name == "nt"
[docs]@DeveloperAPI
class AutoscalingCluster:
"""Create a local autoscaling cluster for testing.
See test_autoscaler_fake_multinode.py for an end-to-end example.
"""
def __init__(
self,
head_resources: dict,
worker_node_types: dict,
autoscaler_v2: bool = False,
**config_kwargs,
):
"""Create the cluster.
Args:
head_resources: resources of the head node, including CPU.
worker_node_types: autoscaler node types config for worker nodes.
"""
self._head_resources = head_resources
self._config = self._generate_config(
head_resources,
worker_node_types,
autoscaler_v2=autoscaler_v2,
**config_kwargs,
)
self._autoscaler_v2 = autoscaler_v2
def _generate_config(
self, head_resources, worker_node_types, autoscaler_v2=False, **config_kwargs
):
base_config = yaml.safe_load(
open(
os.path.join(
os.path.dirname(ray.__file__),
"autoscaler/_private/fake_multi_node/example.yaml",
)
)
)
custom_config = copy.deepcopy(base_config)
custom_config["available_node_types"] = worker_node_types
custom_config["available_node_types"]["ray.head.default"] = {
"resources": head_resources,
"node_config": {},
"max_workers": 0,
}
# Autoscaler v2 specific configs
if autoscaler_v2:
custom_config["provider"]["launch_multiple"] = True
custom_config["provider"]["head_node_id"] = FAKE_HEAD_NODE_ID
custom_config.update(config_kwargs)
return custom_config
[docs] def start(self, _system_config=None, override_env: Optional[Dict] = None):
"""Start the cluster.
After this call returns, you can connect to the cluster with
ray.init("auto").
"""
subprocess.check_call(["ray", "stop", "--force"])
_, fake_config = tempfile.mkstemp()
with open(fake_config, "w") as f:
f.write(json.dumps(self._config))
cmd = [
"ray",
"start",
"--autoscaling-config={}".format(fake_config),
"--head",
]
if "CPU" in self._head_resources:
cmd.append("--num-cpus={}".format(self._head_resources.pop("CPU")))
if "GPU" in self._head_resources:
cmd.append("--num-gpus={}".format(self._head_resources.pop("GPU")))
if "object_store_memory" in self._head_resources:
cmd.append(
"--object-store-memory={}".format(
self._head_resources.pop("object_store_memory")
)
)
if self._head_resources:
cmd.append("--resources='{}'".format(json.dumps(self._head_resources)))
if _system_config is not None:
cmd.append(
"--system-config={}".format(
json.dumps(_system_config, separators=(",", ":"))
)
)
env = os.environ.copy()
env.update({"AUTOSCALER_UPDATE_INTERVAL_S": "1", "RAY_FAKE_CLUSTER": "1"})
if self._autoscaler_v2:
# Set the necessary environment variables for autoscaler v2.
env.update(
{
"RAY_enable_autoscaler_v2": "1",
"RAY_CLOUD_INSTANCE_ID": FAKE_HEAD_NODE_ID,
"RAY_OVERRIDE_NODE_ID_FOR_TESTING": FAKE_HEAD_NODE_ID,
}
)
if override_env:
env.update(override_env)
subprocess.check_call(cmd, env=env)
[docs] def shutdown(self):
"""Terminate the cluster."""
subprocess.check_call(["ray", "stop", "--force"])
@DeveloperAPI
class Cluster:
def __init__(
self,
initialize_head: bool = False,
connect: bool = False,
head_node_args: dict = None,
shutdown_at_exit: bool = True,
):
"""Initializes all services of a Ray cluster.
Args:
initialize_head: Automatically start a Ray cluster
by initializing the head node. Defaults to False.
connect: If `initialize_head=True` and `connect=True`,
ray.init will be called with the address of this cluster
passed in.
head_node_args: Arguments to be passed into
`start_ray_head` via `self.add_node`.
shutdown_at_exit: If True, registers an exit hook
for shutting down all started processes.
"""
if cluster_not_supported:
logger.warning(
"Ray cluster mode is currently experimental and untested on "
"Windows. If you are using it and running into issues please "
"file a report at https://github.com/ray-project/ray/issues."
)
self.head_node = None
self.worker_nodes = set()
self.redis_address = None
self.connected = False
# Create a new global state accessor for fetching GCS table.
self.global_state = ray._private.state.GlobalState()
self._shutdown_at_exit = shutdown_at_exit
if not initialize_head and connect:
raise RuntimeError("Cannot connect to uninitialized cluster.")
if initialize_head:
head_node_args = head_node_args or {}
self.add_node(**head_node_args)
if connect:
self.connect()
@property
def gcs_address(self):
if self.head_node is None:
return None
return self.head_node.gcs_address
@property
def address(self):
return self.gcs_address
def connect(self, namespace=None):
"""Connect the driver to the cluster."""
assert self.address is not None
assert not self.connected
output_info = ray.init(
namespace=namespace,
ignore_reinit_error=True,
address=self.address,
_redis_password=self.redis_password,
)
logger.info(output_info)
self.connected = True
def add_node(self, wait: bool = True, **node_args):
"""Adds a node to the local Ray Cluster.
All nodes are by default started with the following settings:
cleanup=True,
num_cpus=1,
object_store_memory=150 * 1024 * 1024 # 150 MiB
Args:
wait: Whether to wait until the node is alive.
node_args: Keyword arguments used in `start_ray_head` and
`start_ray_node`. Overrides defaults.
Returns:
Node object of the added Ray node.
"""
default_kwargs = {
"num_cpus": 1,
"num_gpus": 0,
"object_store_memory": 150 * 1024 * 1024, # 150 MiB
"min_worker_port": 0,
"max_worker_port": 0,
"dashboard_port": None,
}
ray_params = ray._private.parameter.RayParams(**node_args)
ray_params.update_if_absent(**default_kwargs)
with disable_client_hook():
if self.head_node is None:
node = ray._private.node.Node(
ray_params,
head=True,
shutdown_at_exit=self._shutdown_at_exit,
spawn_reaper=self._shutdown_at_exit,
)
self.head_node = node
self.redis_address = self.head_node.redis_address
self.redis_password = node_args.get(
"redis_password", ray_constants.REDIS_DEFAULT_PASSWORD
)
self.webui_url = self.head_node.webui_url
# Init global state accessor when creating head node.
gcs_options = GcsClientOptions.from_gcs_address(node.gcs_address)
self.global_state._initialize_global_state(gcs_options)
# Write the Ray cluster address for convenience in unit
# testing. ray.init() and ray.init(address="auto") will connect
# to the local cluster.
ray._private.utils.write_ray_address(self.head_node.gcs_address)
else:
ray_params.update_if_absent(redis_address=self.redis_address)
ray_params.update_if_absent(gcs_address=self.gcs_address)
# We only need one log monitor per physical node.
ray_params.update_if_absent(include_log_monitor=False)
# Let grpc pick a port.
ray_params.update_if_absent(node_manager_port=0)
node = ray._private.node.Node(
ray_params,
head=False,
shutdown_at_exit=self._shutdown_at_exit,
spawn_reaper=self._shutdown_at_exit,
)
self.worker_nodes.add(node)
if wait:
# Wait for the node to appear in the client table. We do this
# so that the nodes appears in the client table in the order
# that the corresponding calls to add_node were made. We do
# this because in the tests we assume that the driver is
# connected to the first node that is added.
self._wait_for_node(node)
return node
def remove_node(self, node, allow_graceful=True):
"""Kills all processes associated with worker node.
Args:
node: Worker node of which all associated processes
will be removed.
"""
global_node = ray._private.worker._global_node
if global_node is not None:
if node._raylet_socket_name == global_node._raylet_socket_name:
ray.shutdown()
raise ValueError(
"Removing a node that is connected to this Ray client "
"is not allowed because it will break the driver."
"You can use the get_other_node utility to avoid removing"
"a node that the Ray client is connected."
)
node.destroy_external_storage()
if self.head_node == node:
# We have to wait to prevent the raylet becomes a zombie which will prevent
# worker from exiting
self.head_node.kill_all_processes(
check_alive=False, allow_graceful=allow_graceful, wait=True
)
self.head_node = None
# TODO(rliaw): Do we need to kill all worker processes?
else:
# We have to wait to prevent the raylet becomes a zombie which will prevent
# worker from exiting
node.kill_all_processes(
check_alive=False, allow_graceful=allow_graceful, wait=True
)
self.worker_nodes.remove(node)
assert (
not node.any_processes_alive()
), "There are zombie processes left over after killing."
def _wait_for_node(self, node, timeout: float = 30):
"""Wait until this node has appeared in the client table.
Args:
node (ray._private.node.Node): The node to wait for.
timeout: The amount of time in seconds to wait before raising an
exception.
Raises:
TimeoutError: An exception is raised if the timeout expires before
the node appears in the client table.
"""
ray._private.services.wait_for_node(
node.gcs_address,
node.plasma_store_socket_name,
timeout,
)
def wait_for_nodes(self, timeout: float = 30):
"""Waits for correct number of nodes to be registered.
This will wait until the number of live nodes in the client table
exactly matches the number of "add_node" calls minus the number of
"remove_node" calls that have been made on this cluster. This means
that if a node dies without "remove_node" having been called, this will
raise an exception.
Args:
timeout: The number of seconds to wait for nodes to join
before failing.
Raises:
TimeoutError: An exception is raised if we time out while waiting
for nodes to join.
"""
start_time = time.time()
while time.time() - start_time < timeout:
clients = self.global_state.node_table()
live_clients = [client for client in clients if client["Alive"]]
expected = len(self.list_all_nodes())
if len(live_clients) == expected:
logger.debug("All nodes registered as expected.")
return
else:
logger.debug(
f"{len(live_clients)} nodes are currently registered, "
f"but we are expecting {expected}"
)
time.sleep(0.1)
raise TimeoutError("Timed out while waiting for nodes to join.")
def list_all_nodes(self):
"""Lists all nodes.
TODO(rliaw): What is the desired behavior if a head node
dies before worker nodes die?
Returns:
List of all nodes, including the head node.
"""
nodes = list(self.worker_nodes)
if self.head_node:
nodes = [self.head_node] + nodes
return nodes
def remaining_processes_alive(self):
"""Returns a bool indicating whether all processes are alive or not.
Note that this ignores processes that have been explicitly killed,
e.g., via a command like node.kill_raylet().
Returns:
True if all processes are alive and false otherwise.
"""
return all(node.remaining_processes_alive() for node in self.list_all_nodes())
def shutdown(self):
"""Removes all nodes."""
# We create a list here as a copy because `remove_node`
# modifies `self.worker_nodes`.
all_nodes = list(self.worker_nodes)
for node in all_nodes:
self.remove_node(node)
if self.head_node is not None:
self.remove_node(self.head_node)
# need to reset internal kv since gcs is down
ray.experimental.internal_kv._internal_kv_reset()
# Delete the cluster address.
ray._private.utils.reset_ray_address()