class RestartableLongPollHost:
def __init__(self) -> None:
print("actor started")
self.host = LongPollHost()
self.host.notify_changed("timer", time.time())
self.should_exit = False
async def listen_for_change(self, key_to_ids):
print("listening for change ", key_to_ids)
return await self.host.listen_for_change(key_to_ids)
async def set_exit(self):
self.should_exit = True
async def exit_if_set(self):
if self.should_exit:
print("actor exit")
os._exit(1)
class MockControllerActor:
def __init__(self):
from ray.serve.long_poll import LongPollHost
self.host = LongPollHost()
self.backend_replicas = defaultdict(list)
self.backend_configs = dict()
async def listen_for_change(self, snapshot_ids):
return await self.host.listen_for_change(snapshot_ids)
def set_traffic(self, endpoint, traffic_policy):
self.host.notify_changed(
(LongPollNamespace.TRAFFIC_POLICIES, endpoint), traffic_policy)
def add_new_replica(self,
backend_tag,
runner_actor,
backend_config=BackendConfig()):
self.backend_replicas[backend_tag].append(runner_actor)
self.backend_configs[backend_tag] = backend_config
ray.get(runner_actor.reconfigure.remote(
backend_config.user_config))
self.host.notify_changed(
(LongPollNamespace.REPLICA_HANDLES, backend_tag),
self.backend_replicas[backend_tag],
)
self.host.notify_changed(
(LongPollNamespace.BACKEND_CONFIGS, backend_tag),
self.backend_configs[backend_tag],
)
def update_backend(self, backend_tag: str,
backend_config: BackendConfig):
self.backend_configs[backend_tag] = backend_config
self.host.notify_changed(
(LongPollNamespace.BACKEND_CONFIGS, backend_tag),
self.backend_configs[backend_tag],
)
ray.get([
r.reconfigure.remote(backend_config.user_config)
for r in self.backend_replicas[backend_tag]
])
class ServeController:
"""Responsible for managing the state of the serving system.
The controller implements fault tolerance by persisting its state in
a new checkpoint each time a state change is made. If the actor crashes,
the latest checkpoint is loaded and the state is recovered. Checkpoints
are written/read using a provided KV-store interface.
All hard state in the system is maintained by this actor and persisted via
these checkpoints. Soft state required by other components is fetched by
those actors from this actor on startup and updates are pushed out from
this actor.
All other actors started by the controller are named, detached actors
so they will not fate share with the controller if it crashes.
The following guarantees are provided for state-changing calls to the
controller:
- If the call succeeds, the change was made and will be reflected in
the system even if the controller or other actors die unexpectedly.
- If the call fails, the change may have been made but isn't guaranteed
to have been. The client should retry in this case. Note that this
requires all implementations here to be idempotent.
"""
async def __init__(self,
controller_name: str,
http_host: str,
http_port: str,
http_middlewares: List[Any],
detached: bool = False):
# Used to read/write checkpoints.
self.kv_store = RayInternalKVStore(namespace=controller_name)
# Current State
self.current_state = SystemState()
# Goal State
# TODO(ilr) This is currently *unused* until the refactor of the serve
# controller.
self.goal_state = SystemState()
# ActorStateReconciler
self.actor_reconciler = ActorStateReconciler(controller_name, detached)
# backend -> AutoscalingPolicy
self.autoscaling_policies = dict()
# Dictionary of backend_tag -> proxy_name -> most recent queue length.
self.backend_stats = defaultdict(lambda: defaultdict(dict))
# Used to ensure that only a single state-changing operation happens
# at any given time.
self.write_lock = asyncio.Lock()
self.http_host = http_host
self.http_port = http_port
self.http_middlewares = http_middlewares
# If starting the actor for the first time, starts up the other system
# components. If recovering, fetches their actor handles.
self.actor_reconciler._start_http_proxies_if_needed(
self.http_host, self.http_port, self.http_middlewares)
# Map of awaiting results
# TODO(ilr): Checkpoint this once this becomes asynchronous
self.inflight_results: Dict[UUID, asyncio.Event] = dict()
self._serializable_inflight_results: Dict[UUID, FutureResult] = dict()
checkpoint = self.kv_store.get(CHECKPOINT_KEY)
if checkpoint is None:
logger.debug("No checkpoint found")
else:
await self._recover_from_checkpoint(checkpoint)
# NOTE(simon): Currently we do all-to-all broadcast. This means
# any listeners will receive notification for all changes. This
# can be problem at scale, e.g. updating a single backend config
# will send over the entire configs. In the future, we should
# optimize the logic to support subscription by key.
self.long_poll_host = LongPollHost()
# The configs pushed out here get updated by
# self._recover_from_checkpoint in the failure scenario, so that must
# be run before we notify the changes.
self.notify_backend_configs_changed()
self.notify_replica_handles_changed()
self.notify_traffic_policies_changed()
self.notify_route_table_changed()
asyncio.get_event_loop().create_task(self.run_control_loop())
async def wait_for_event(self, uuid: UUID) -> bool:
if uuid not in self.inflight_results:
return True
event = self.inflight_results[uuid]
await event.wait()
self.inflight_results.pop(uuid)
self._serializable_inflight_results.pop(uuid)
async with self.write_lock:
self._checkpoint()
return True
def _create_event_with_result(
self,
goal_state: Dict[str, any],
recreation_uuid: Optional[UUID] = None) -> UUID:
# NOTE(ilr) Must be called before checkpointing!
event = asyncio.Event()
event.result = FutureResult(goal_state)
event.set()
uuid_val = recreation_uuid or uuid4()
self.inflight_results[uuid_val] = event
self._serializable_inflight_results[uuid_val] = event.result
return uuid_val
async def _num_inflight_results(self) -> int:
return len(self.inflight_results)
def notify_replica_handles_changed(self):
self.long_poll_host.notify_changed(
LongPollKey.REPLICA_HANDLES, {
backend_tag: list(replica_dict.values())
for backend_tag, replica_dict in
self.actor_reconciler.backend_replicas.items()
})
def notify_traffic_policies_changed(self):
self.long_poll_host.notify_changed(
LongPollKey.TRAFFIC_POLICIES,
self.current_state.traffic_policies,
)
def notify_backend_configs_changed(self):
self.long_poll_host.notify_changed(
LongPollKey.BACKEND_CONFIGS,
self.current_state.get_backend_configs())
def notify_route_table_changed(self):
self.long_poll_host.notify_changed(LongPollKey.ROUTE_TABLE,
self.current_state.routes)
async def listen_for_change(self, keys_to_snapshot_ids: Dict[str, int]):
"""Proxy long pull client's listen request.
Args:
keys_to_snapshot_ids (Dict[str, int]): Snapshot IDs are used to
determine whether or not the host should immediately return the
data or wait for the value to be changed.
"""
return await (
self.long_poll_host.listen_for_change(keys_to_snapshot_ids))
def get_http_proxies(self) -> Dict[str, ActorHandle]:
"""Returns a dictionary of node ID to http_proxy actor handles."""
return self.actor_reconciler.http_proxy_cache
def _checkpoint(self) -> None:
"""Checkpoint internal state and write it to the KV store."""
assert self.write_lock.locked()
logger.debug("Writing checkpoint")
start = time.time()
checkpoint = pickle.dumps(
Checkpoint(self.goal_state, self.current_state,
self.actor_reconciler,
self._serializable_inflight_results))
self.kv_store.put(CHECKPOINT_KEY, checkpoint)
logger.debug("Wrote checkpoint in {:.2f}".format(time.time() - start))
if random.random(
) < _CRASH_AFTER_CHECKPOINT_PROBABILITY and self.detached:
logger.warning("Intentionally crashing after checkpoint")
os._exit(0)
async def _recover_from_checkpoint(self, checkpoint_bytes: bytes) -> None:
"""Recover the instance state from the provided checkpoint.
This should be called in the constructor to ensure that the internal
state is updated before any other operations run. After running this,
internal state will be updated and long-poll clients may be notified.
Performs the following operations:
1) Deserializes the internal state from the checkpoint.
2) Starts/stops any replicas that are pending creation or
deletion.
"""
start = time.time()
logger.info("Recovering from checkpoint")
restored_checkpoint: Checkpoint = pickle.loads(checkpoint_bytes)
self.current_state = restored_checkpoint.current_state
self.actor_reconciler = restored_checkpoint.reconciler
self._serializable_inflight_results = restored_checkpoint.inflight_reqs
for uuid, fut_result in self._serializable_inflight_results.items():
self._create_event_with_result(fut_result.requested_goal, uuid)
# NOTE(edoakes): unfortunately, we can't completely recover from a
# checkpoint in the constructor because we block while waiting for
# other actors to start up, and those actors fetch soft state from
# this actor. Because no other tasks will start executing until after
# the constructor finishes, if we were to run this logic in the
# constructor it could lead to deadlock between this actor and a child.
# However, we do need to guarantee that we have fully recovered from a
# checkpoint before any other state-changing calls run. We address this
# by acquiring the write_lock and then posting the task to recover from
# a checkpoint to the event loop. Other state-changing calls acquire
# this lock and will be blocked until recovering from the checkpoint
# finishes. This can be removed once we move to the async control loop.
async def finish_recover_from_checkpoint():
assert self.write_lock.locked()
self.autoscaling_policies = await self.actor_reconciler.\
_recover_from_checkpoint(self.current_state, self)
self.write_lock.release()
logger.info(
"Recovered from checkpoint in {:.3f}s".format(time.time() -
start))
await self.write_lock.acquire()
asyncio.get_event_loop().create_task(finish_recover_from_checkpoint())
async def do_autoscale(self) -> None:
for backend, info in self.current_state.backends.items():
if backend not in self.autoscaling_policies:
continue
new_num_replicas = self.autoscaling_policies[backend].scale(
self.backend_stats[backend], info.backend_config.num_replicas)
if new_num_replicas > 0:
await self.update_backend_config(
backend, BackendConfig(num_replicas=new_num_replicas))
async def reconcile_current_and_goal_backends(self):
pass
# backends_to_delete = set(
# self.current_state.backends.keys()).difference(
# self.goal_state.backends.keys())
async def run_control_loop(self) -> None:
while True:
await self.do_autoscale()
async with self.write_lock:
self.actor_reconciler._start_http_proxies_if_needed(
self.http_host, self.http_port, self.http_middlewares)
checkpoint_required = self.actor_reconciler.\
_stop_http_proxies_if_needed()
if checkpoint_required:
self._checkpoint()
await asyncio.sleep(CONTROL_LOOP_PERIOD_S)
def _all_replica_handles(
self) -> Dict[BackendTag, Dict[ReplicaTag, ActorHandle]]:
"""Used for testing."""
return self.actor_reconciler.backend_replicas
def get_all_backends(self) -> Dict[BackendTag, BackendConfig]:
"""Returns a dictionary of backend tag to backend config."""
return self.current_state.get_backend_configs()
def get_all_endpoints(self) -> Dict[EndpointTag, Dict[BackendTag, Any]]:
"""Returns a dictionary of backend tag to backend config."""
return self.current_state.get_endpoints()
async def _set_traffic(self, endpoint_name: str,
traffic_dict: Dict[str, float]) -> UUID:
if endpoint_name not in self.current_state.get_endpoints():
raise ValueError("Attempted to assign traffic for an endpoint '{}'"
" that is not registered.".format(endpoint_name))
assert isinstance(traffic_dict,
dict), "Traffic policy must be a dictionary."
for backend in traffic_dict:
if self.current_state.get_backend(backend) is None:
raise ValueError(
"Attempted to assign traffic to a backend '{}' that "
"is not registered.".format(backend))
traffic_policy = TrafficPolicy(traffic_dict)
self.current_state.traffic_policies[endpoint_name] = traffic_policy
return_uuid = self._create_event_with_result(
{endpoint_name: traffic_policy})
# NOTE(edoakes): we must write a checkpoint before pushing the
# update to avoid inconsistent state if we crash after pushing the
# update.
self._checkpoint()
self.notify_traffic_policies_changed()
return return_uuid
async def set_traffic(self, endpoint_name: str,
traffic_dict: Dict[str, float]) -> UUID:
"""Sets the traffic policy for the specified endpoint."""
async with self.write_lock:
return_uuid = await self._set_traffic(endpoint_name, traffic_dict)
return return_uuid
async def shadow_traffic(self, endpoint_name: str, backend_tag: BackendTag,
proportion: float) -> UUID:
"""Shadow traffic from the endpoint to the backend."""
async with self.write_lock:
if endpoint_name not in self.current_state.get_endpoints():
raise ValueError(
"Attempted to shadow traffic from an "
"endpoint '{}' that is not registered.".format(
endpoint_name))
if self.current_state.get_backend(backend_tag) is None:
raise ValueError(
"Attempted to shadow traffic to a backend '{}' that "
"is not registered.".format(backend_tag))
self.current_state.traffic_policies[endpoint_name].set_shadow(
backend_tag, proportion)
traffic_policy = self.current_state.traffic_policies[endpoint_name]
return_uuid = self._create_event_with_result(
{endpoint_name: traffic_policy})
# NOTE(edoakes): we must write a checkpoint before pushing the
# update to avoid inconsistent state if we crash after pushing the
# update.
self._checkpoint()
self.notify_traffic_policies_changed()
return return_uuid
# TODO(architkulkarni): add Optional for route after cloudpickle upgrade
async def create_endpoint(self, endpoint: str, traffic_dict: Dict[str,
float],
route, methods) -> UUID:
"""Create a new endpoint with the specified route and methods.
If the route is None, this is a "headless" endpoint that will not
be exposed over HTTP and can only be accessed via a handle.
"""
async with self.write_lock:
# If this is a headless endpoint with no route, key the endpoint
# based on its name.
# TODO(edoakes): we should probably just store routes and endpoints
# separately.
if route is None:
route = endpoint
# TODO(edoakes): move this to client side.
err_prefix = "Cannot create endpoint."
if route in self.current_state.routes:
# Ensures this method is idempotent
if self.current_state.routes[route] == (endpoint, methods):
return
else:
raise ValueError(
"{} Route '{}' is already registered.".format(
err_prefix, route))
if endpoint in self.current_state.get_endpoints():
raise ValueError(
"{} Endpoint '{}' is already registered.".format(
err_prefix, endpoint))
logger.info(
"Registering route '{}' to endpoint '{}' with methods '{}'.".
format(route, endpoint, methods))
self.current_state.routes[route] = (endpoint, methods)
# NOTE(edoakes): checkpoint is written in self._set_traffic.
return_uuid = await self._set_traffic(endpoint, traffic_dict)
self.notify_route_table_changed()
return return_uuid
async def delete_endpoint(self, endpoint: str) -> UUID:
"""Delete the specified endpoint.
Does not modify any corresponding backends.
"""
logger.info("Deleting endpoint '{}'".format(endpoint))
async with self.write_lock:
# This method must be idempotent. We should validate that the
# specified endpoint exists on the client.
for route, (route_endpoint,
_) in self.current_state.routes.items():
if route_endpoint == endpoint:
route_to_delete = route
break
else:
logger.info("Endpoint '{}' doesn't exist".format(endpoint))
return
# Remove the routing entry.
del self.current_state.routes[route_to_delete]
# Remove the traffic policy entry if it exists.
if endpoint in self.current_state.traffic_policies:
del self.current_state.traffic_policies[endpoint]
return_uuid = self._create_event_with_result({
route_to_delete: None,
endpoint: None
})
# NOTE(edoakes): we must write a checkpoint before pushing the
# updates to the proxies to avoid inconsistent state if we crash
# after pushing the update.
self._checkpoint()
self.notify_route_table_changed()
return return_uuid
async def create_backend(self, backend_tag: BackendTag,
backend_config: BackendConfig,
replica_config: ReplicaConfig) -> UUID:
"""Register a new backend under the specified tag."""
async with self.write_lock:
# Ensures this method is idempotent.
backend_info = self.current_state.get_backend(backend_tag)
if backend_info is not None:
if (backend_info.backend_config == backend_config
and backend_info.replica_config == replica_config):
return
backend_replica = create_backend_replica(
replica_config.func_or_class)
# Save creator that starts replicas, the arguments to be passed in,
# and the configuration for the backends.
backend_info = BackendInfo(worker_class=backend_replica,
backend_config=backend_config,
replica_config=replica_config)
self.current_state.add_backend(backend_tag, backend_info)
metadata = backend_config.internal_metadata
if metadata.autoscaling_config is not None:
self.autoscaling_policies[
backend_tag] = BasicAutoscalingPolicy(
backend_tag, metadata.autoscaling_config)
try:
# This call should be to run control loop
self.actor_reconciler._scale_backend_replicas(
self.current_state.backends, backend_tag,
backend_config.num_replicas)
except RayServeException as e:
del self.current_state.backends[backend_tag]
raise e
return_uuid = self._create_event_with_result(
{backend_tag: backend_info})
# NOTE(edoakes): we must write a checkpoint before starting new
# or pushing the updated config to avoid inconsistent state if we
# crash while making the change.
self._checkpoint()
await self.actor_reconciler._enqueue_pending_scale_changes_loop(
self.current_state)
await self.actor_reconciler.backend_control_loop()
self.notify_replica_handles_changed()
# Set the backend config inside routers
# (particularly for max_concurrent_queries).
self.notify_backend_configs_changed()
return return_uuid
async def delete_backend(self, backend_tag: BackendTag) -> UUID:
async with self.write_lock:
# This method must be idempotent. We should validate that the
# specified backend exists on the client.
if self.current_state.get_backend(backend_tag) is None:
return
# Check that the specified backend isn't used by any endpoints.
for endpoint, traffic_policy in self.current_state.\
traffic_policies.items():
if (backend_tag in traffic_policy.traffic_dict
or backend_tag in traffic_policy.shadow_dict):
raise ValueError("Backend '{}' is used by endpoint '{}' "
"and cannot be deleted. Please remove "
"the backend from all endpoints and try "
"again.".format(backend_tag, endpoint))
# Scale its replicas down to 0. This will also remove the backend
# from self.current_state.backends and
# self.actor_reconciler.backend_replicas.
self.goal_state.backends[backend_tag] = None
# This should be a call to the control loop
self.actor_reconciler._scale_backend_replicas(
self.current_state.backends, backend_tag, 0)
# Remove the backend's metadata.
del self.current_state.backends[backend_tag]
if backend_tag in self.autoscaling_policies:
del self.autoscaling_policies[backend_tag]
# Add the intention to remove the backend from the routers.
self.actor_reconciler.backends_to_remove.append(backend_tag)
return_uuid = self._create_event_with_result({backend_tag: None})
# NOTE(edoakes): we must write a checkpoint before removing the
# backend from the routers to avoid inconsistent state if we crash
# after pushing the update.
self._checkpoint()
await self.actor_reconciler._enqueue_pending_scale_changes_loop(
self.current_state)
await self.actor_reconciler.backend_control_loop()
self.notify_replica_handles_changed()
return return_uuid
async def update_backend_config(self, backend_tag: BackendTag,
config_options: BackendConfig) -> UUID:
"""Set the config for the specified backend."""
async with self.write_lock:
assert (self.current_state.get_backend(backend_tag)
), "Backend {} is not registered.".format(backend_tag)
assert isinstance(config_options, BackendConfig)
stored_backend_config = self.current_state.get_backend(
backend_tag).backend_config
backend_config = stored_backend_config.copy(
update=config_options.dict(exclude_unset=True))
backend_config._validate_complete()
self.current_state.get_backend(
backend_tag).backend_config = backend_config
backend_info = self.current_state.get_backend(backend_tag)
# Scale the replicas with the new configuration.
# This should be to run the control loop
self.actor_reconciler._scale_backend_replicas(
self.current_state.backends, backend_tag,
backend_config.num_replicas)
return_uuid = self._create_event_with_result(
{backend_tag: backend_info})
# NOTE(edoakes): we must write a checkpoint before pushing the
# update to avoid inconsistent state if we crash after pushing the
# update.
self._checkpoint()
# Inform the routers about change in configuration
# (particularly for setting max_batch_size).
await self.actor_reconciler._enqueue_pending_scale_changes_loop(
self.current_state)
await self.actor_reconciler.backend_control_loop()
self.notify_replica_handles_changed()
self.notify_backend_configs_changed()
return return_uuid
def get_backend_config(self, backend_tag: BackendTag) -> BackendConfig:
"""Get the current config for the specified backend."""
assert (self.current_state.get_backend(backend_tag)
), "Backend {} is not registered.".format(backend_tag)
return self.current_state.get_backend(backend_tag).backend_config
def get_http_config(self):
"""Return the HTTP proxy configuration."""
return self.http_host, self.http_port
async def shutdown(self) -> None:
"""Shuts down the serve instance completely."""
async with self.write_lock:
for http_proxy in self.actor_reconciler.http_proxy_handles():
ray.kill(http_proxy, no_restart=True)
for replica in self.actor_reconciler.get_replica_handles():
ray.kill(replica, no_restart=True)
self.kv_store.delete(CHECKPOINT_KEY)
class MockControllerActor:
def __init__(self):
from ray.serve.long_poll import LongPollHost
self.host = LongPollHost()
self.backend_replicas = defaultdict(list)
self.backend_configs = dict()
self.clear()
def clear(self):
self.host.notify_changed(LongPollKey.REPLICA_HANDLES, {})
self.host.notify_changed(LongPollKey.TRAFFIC_POLICIES, {})
self.host.notify_changed(LongPollKey.BACKEND_CONFIGS, {})
async def listen_for_change(self, snapshot_ids):
return await self.host.listen_for_change(snapshot_ids)
def set_traffic(self, endpoint, traffic_policy):
self.host.notify_changed(LongPollKey.TRAFFIC_POLICIES,
{endpoint: traffic_policy})
def add_new_replica(self,
backend_tag,
runner_actor,
backend_config=BackendConfig()):
self.backend_replicas[backend_tag].append(runner_actor)
self.backend_configs[backend_tag] = backend_config
self.host.notify_changed(
LongPollKey.REPLICA_HANDLES,
self.backend_replicas,
)
self.host.notify_changed(LongPollKey.BACKEND_CONFIGS,
self.backend_configs)
def update_backend(self, backend_tag: str,
backend_config: BackendConfig):
self.backend_configs[backend_tag] = backend_config
self.host.notify_changed(LongPollKey.BACKEND_CONFIGS,
self.backend_configs)
class ServeController:
"""Responsible for managing the state of the serving system.
The controller implements fault tolerance by persisting its state in
a new checkpoint each time a state change is made. If the actor crashes,
the latest checkpoint is loaded and the state is recovered. Checkpoints
are written/read using a provided KV-store interface.
All hard state in the system is maintained by this actor and persisted via
these checkpoints. Soft state required by other components is fetched by
those actors from this actor on startup and updates are pushed out from
this actor.
All other actors started by the controller are named, detached actors
so they will not fate share with the controller if it crashes.
The following guarantees are provided for state-changing calls to the
controller:
- If the call succeeds, the change was made and will be reflected in
the system even if the controller or other actors die unexpectedly.
- If the call fails, the change may have been made but isn't guaranteed
to have been. The client should retry in this case. Note that this
requires all implementations here to be idempotent.
"""
async def __init__(self,
controller_name: str,
http_config: HTTPOptions,
detached: bool = False):
# Used to read/write checkpoints.
self.kv_store = RayInternalKVStore(namespace=controller_name)
# Dictionary of backend_tag -> proxy_name -> most recent queue length.
self.backend_stats = defaultdict(lambda: defaultdict(dict))
# Used to ensure that only a single state-changing operation happens
# at any given time.
self.write_lock = asyncio.Lock()
# Map of awaiting results
# TODO(ilr): Checkpoint this once this becomes asynchronous
self.inflight_results: Dict[UUID, asyncio.Event] = dict()
self._serializable_inflight_results: Dict[UUID, FutureResult] = dict()
# NOTE(simon): Currently we do all-to-all broadcast. This means
# any listeners will receive notification for all changes. This
# can be problem at scale, e.g. updating a single backend config
# will send over the entire configs. In the future, we should
# optimize the logic to support subscription by key.
self.long_poll_host = LongPollHost()
self.http_state = HTTPState(controller_name, detached, http_config)
self.endpoint_state = EndpointState(self.kv_store, self.long_poll_host)
checkpoint_bytes = self.kv_store.get(CHECKPOINT_KEY)
if checkpoint_bytes is None:
logger.debug("No checkpoint found")
self.backend_state = BackendState(controller_name, detached)
else:
checkpoint: Checkpoint = pickle.loads(checkpoint_bytes)
self.backend_state = BackendState(
controller_name,
detached,
checkpoint=checkpoint.backend_state_checkpoint)
self._serializable_inflight_results = checkpoint.inflight_reqs
for uuid, fut_result in self._serializable_inflight_results.items(
):
self._create_event_with_result(fut_result.requested_goal, uuid)
self.notify_backend_configs_changed()
self.notify_replica_handles_changed()
asyncio.get_event_loop().create_task(self.run_control_loop())
async def wait_for_event(self, uuid: UUID) -> bool:
start = time.time()
if uuid not in self.inflight_results:
logger.debug(f"UUID ({uuid}) not found!!!")
return True
event = self.inflight_results[uuid]
await event.wait()
self.inflight_results.pop(uuid)
self._serializable_inflight_results.pop(uuid)
async with self.write_lock:
self._checkpoint()
logger.debug(f"Waiting for {uuid} took {time.time() - start} seconds")
return True
def _create_event_with_result(
self,
goal_state: Dict[str, any],
recreation_uuid: Optional[UUID] = None) -> UUID:
# NOTE(ilr) Must be called before checkpointing!
event = asyncio.Event()
event.result = FutureResult(goal_state)
uuid_val = recreation_uuid or uuid4()
self.inflight_results[uuid_val] = event
self._serializable_inflight_results[uuid_val] = event.result
return uuid_val
async def _num_inflight_results(self) -> int:
return len(self.inflight_results)
def notify_replica_handles_changed(self):
self.long_poll_host.notify_changed(
LongPollKey.REPLICA_HANDLES, {
backend_tag: list(replica_dict.values())
for backend_tag, replica_dict in
self.backend_state.backend_replicas.items()
})
def notify_backend_configs_changed(self):
self.long_poll_host.notify_changed(
LongPollKey.BACKEND_CONFIGS,
self.backend_state.get_backend_configs())
async def listen_for_change(self, keys_to_snapshot_ids: Dict[str, int]):
"""Proxy long pull client's listen request.
Args:
keys_to_snapshot_ids (Dict[str, int]): Snapshot IDs are used to
determine whether or not the host should immediately return the
data or wait for the value to be changed.
"""
return await (
self.long_poll_host.listen_for_change(keys_to_snapshot_ids))
def get_http_proxies(self) -> Dict[NodeId, ActorHandle]:
"""Returns a dictionary of node ID to http_proxy actor handles."""
return self.http_state.get_http_proxy_handles()
def _checkpoint(self) -> None:
"""Checkpoint internal state and write it to the KV store."""
assert self.write_lock.locked()
logger.debug("Writing checkpoint")
start = time.time()
checkpoint = pickle.dumps(
Checkpoint(self.backend_state.checkpoint(),
self._serializable_inflight_results))
self.kv_store.put(CHECKPOINT_KEY, checkpoint)
logger.debug("Wrote checkpoint in {:.3f}s".format(time.time() - start))
if random.random(
) < _CRASH_AFTER_CHECKPOINT_PROBABILITY and self.detached:
logger.warning("Intentionally crashing after checkpoint")
os._exit(0)
async def reconcile_current_and_goal_backends(self):
pass
def set_goal_id(self, goal_id: UUID) -> None:
event = self.inflight_results.get(goal_id)
logger.debug(f"Setting goal id {goal_id}")
if event:
event.set()
async def run_control_loop(self) -> None:
while True:
async with self.write_lock:
self.http_state.update()
completed_ids = self.backend_state.completed_goals()
for done_id in completed_ids:
self.set_goal_id(done_id)
delta_workers = await self.backend_state.update()
if delta_workers:
self.notify_replica_handles_changed()
self._checkpoint()
await asyncio.sleep(CONTROL_LOOP_PERIOD_S)
def _all_replica_handles(
self) -> Dict[BackendTag, Dict[ReplicaTag, ActorHandle]]:
"""Used for testing."""
return self.backend_state.get_replica_handles()
def get_all_backends(self) -> Dict[BackendTag, BackendConfig]:
"""Returns a dictionary of backend tag to backend config."""
return self.backend_state.get_backend_configs()
def get_all_endpoints(self) -> Dict[EndpointTag, Dict[BackendTag, Any]]:
"""Returns a dictionary of backend tag to backend config."""
return self.endpoint_state.get_endpoints()
def _set_traffic(self, endpoint_name: str,
traffic_dict: Dict[str, float]) -> UUID:
for backend in traffic_dict:
if self.backend_state.get_backend(backend) is None:
raise ValueError(
"Attempted to assign traffic to a backend '{}' that "
"is not registered.".format(backend))
self.endpoint_state.set_traffic_policy(endpoint_name,
TrafficPolicy(traffic_dict))
def _validate_traffic_dict(self, traffic_dict: Dict[str, float]):
for backend in traffic_dict:
if self.backend_state.get_backend(backend) is None:
raise ValueError(
"Attempted to assign traffic to a backend '{}' that "
"is not registered.".format(backend))
async def set_traffic(self, endpoint_name: str,
traffic_dict: Dict[str, float]) -> None:
"""Sets the traffic policy for the specified endpoint."""
async with self.write_lock:
self._validate_traffic_dict(traffic_dict)
self._set_traffic(endpoint_name, traffic_dict)
async def shadow_traffic(self, endpoint_name: str, backend_tag: BackendTag,
proportion: float) -> UUID:
"""Shadow traffic from the endpoint to the backend."""
async with self.write_lock:
if self.backend_state.get_backend(backend_tag) is None:
raise ValueError(
"Attempted to shadow traffic to a backend '{}' that "
"is not registered.".format(backend_tag))
logger.info(
"Shadowing '{}' of traffic to endpoint '{}' to backend '{}'.".
format(proportion, endpoint_name, backend_tag))
self.endpoint_state.shadow_traffic(endpoint_name, backend_tag,
proportion)
# TODO(architkulkarni): add Optional for route after cloudpickle upgrade
async def create_endpoint(self, endpoint: str,
traffic_dict: Dict[str, float], route,
methods: List[str]) -> UUID:
"""Create a new endpoint with the specified route and methods.
If the route is None, this is a "headless" endpoint that will not
be exposed over HTTP and can only be accessed via a handle.
"""
async with self.write_lock:
self._validate_traffic_dict(traffic_dict)
logger.info(
"Registering route '{}' to endpoint '{}' with methods '{}'.".
format(route, endpoint, methods))
self.endpoint_state.create_endpoint(endpoint, route, methods,
TrafficPolicy(traffic_dict))
async def delete_endpoint(self, endpoint: str) -> None:
"""Delete the specified endpoint.
Does not modify any corresponding backends.
"""
logger.info("Deleting endpoint '{}'".format(endpoint))
async with self.write_lock:
self.endpoint_state.delete_endpoint(endpoint)
async def set_backend_goal(self, backend_tag: BackendTag,
backend_info: BackendInfo,
new_id: GoalId) -> None:
# NOTE(ilr) Must checkpoint after doing this!
existing_id_to_set = self.backend_state._set_backend_goal(
backend_tag, backend_info, new_id)
if existing_id_to_set:
self.set_goal_id(existing_id_to_set)
async def create_backend(self, backend_tag: BackendTag,
backend_config: BackendConfig,
replica_config: ReplicaConfig) -> UUID:
"""Register a new backend under the specified tag."""
async with self.write_lock:
# Ensures this method is idempotent.
backend_info = self.backend_state.get_backend(backend_tag)
if backend_info is not None:
if (backend_info.backend_config == backend_config
and backend_info.replica_config == replica_config):
return
backend_replica = create_backend_replica(
replica_config.func_or_class)
# Save creator that starts replicas, the arguments to be passed in,
# and the configuration for the backends.
backend_info = BackendInfo(
worker_class=backend_replica,
backend_config=backend_config,
replica_config=replica_config)
return_uuid = self._create_event_with_result({
backend_tag: backend_info
})
await self.set_backend_goal(backend_tag, backend_info, return_uuid)
try:
# This call should be to run control loop
self.backend_state.scale_backend_replicas(
backend_tag, backend_config.num_replicas)
except RayServeException as e:
del self.backend_state.backends[backend_tag]
raise e
# NOTE(edoakes): we must write a checkpoint before starting new
# or pushing the updated config to avoid inconsistent state if we
# crash while making the change.
self._checkpoint()
self.notify_backend_configs_changed()
return return_uuid
async def delete_backend(self,
backend_tag: BackendTag,
force_kill: bool = False) -> UUID:
async with self.write_lock:
# This method must be idempotent. We should validate that the
# specified backend exists on the client.
if self.backend_state.get_backend(backend_tag) is None:
return
# Check that the specified backend isn't used by any endpoints.
for endpoint, info in self.endpoint_state.get_endpoints().items():
if (backend_tag in info["traffic"]
or backend_tag in info["shadows"]):
raise ValueError("Backend '{}' is used by endpoint '{}' "
"and cannot be deleted. Please remove "
"the backend from all endpoints and try "
"again.".format(backend_tag, endpoint))
# Scale its replicas down to 0.
self.backend_state.scale_backend_replicas(backend_tag, 0,
force_kill)
# Remove the backend's metadata.
del self.backend_state.backends[backend_tag]
# Add the intention to remove the backend from the routers.
self.backend_state.backends_to_remove.append(backend_tag)
return_uuid = self._create_event_with_result({backend_tag: None})
# Remove the backend's metadata.
await self.set_backend_goal(backend_tag, None, return_uuid)
# NOTE(edoakes): we must write a checkpoint before removing the
# backend from the routers to avoid inconsistent state if we crash
# after pushing the update.
self._checkpoint()
return return_uuid
async def update_backend_config(self, backend_tag: BackendTag,
config_options: BackendConfig) -> UUID:
"""Set the config for the specified backend."""
async with self.write_lock:
assert (self.backend_state.get_backend(backend_tag)
), "Backend {} is not registered.".format(backend_tag)
assert isinstance(config_options, BackendConfig)
stored_backend_config = self.backend_state.get_backend(
backend_tag).backend_config
backend_config = stored_backend_config.copy(
update=config_options.dict(exclude_unset=True))
backend_config._validate_complete()
self.backend_state.get_backend(
backend_tag).backend_config = backend_config
backend_info = self.backend_state.get_backend(backend_tag)
return_uuid = self._create_event_with_result({
backend_tag: backend_info
})
await self.set_backend_goal(backend_tag, backend_info, return_uuid)
# Scale the replicas with the new configuration.
# This should be to run the control loop
self.backend_state.scale_backend_replicas(
backend_tag, backend_config.num_replicas)
# NOTE(edoakes): we must write a checkpoint before pushing the
# update to avoid inconsistent state if we crash after pushing the
# update.
self._checkpoint()
# Inform the routers and backend replicas about config changes.
self.notify_backend_configs_changed()
return return_uuid
def get_backend_config(self, backend_tag: BackendTag) -> BackendConfig:
"""Get the current config for the specified backend."""
assert (self.backend_state.get_backend(backend_tag)
), "Backend {} is not registered.".format(backend_tag)
return self.backend_state.get_backend(backend_tag).backend_config
def get_http_config(self):
"""Return the HTTP proxy configuration."""
return self.http_state.get_config()
async def shutdown(self) -> None:
"""Shuts down the serve instance completely."""
async with self.write_lock:
for proxy in self.http_state.get_http_proxy_handles().values():
ray.kill(proxy, no_restart=True)
for replica_dict in self.backend_state.get_replica_handles(
).values():
for replica in replica_dict.values():
ray.kill(replica, no_restart=True)
self.kv_store.delete(CHECKPOINT_KEY)
