import asyncio
import bisect
import concurrent.futures
import errno
import heapq
import logging
import os
import random
import sys
import threading
import warnings
import weakref
from collections import defaultdict, deque, namedtuple
from collections.abc import MutableMapping
from contextlib import suppress
from datetime import timedelta
from inspect import isawaitable
from pickle import PicklingError
from typing import Dict, Iterable, Optional
from tlz import first, keymap, merge, pluck # noqa: F401
from tornado import gen
from tornado.ioloop import IOLoop, PeriodicCallback
import dask
from dask.core import istask
from dask.system import CPU_COUNT
from dask.utils import apply, format_bytes, funcname
from . import comm, preloading, profile, system, utils
from .batched import BatchedSend
from .comm import connect, get_address_host
from .comm.addressing import address_from_user_args
from .comm.utils import OFFLOAD_THRESHOLD
from .core import (
CommClosedError,
Status,
coerce_to_address,
error_message,
pingpong,
send_recv,
)
from .diagnostics import nvml
from .diagnostics.plugin import _get_worker_plugin_name
from .diskutils import WorkSpace
from .http import get_handlers
from .metrics import time
from .node import ServerNode
from .proctitle import setproctitle
from .protocol import pickle, to_serialize
from .pubsub import PubSubWorkerExtension
from .security import Security
from .sizeof import safe_sizeof as sizeof
from .threadpoolexecutor import ThreadPoolExecutor
from .threadpoolexecutor import secede as tpe_secede
from .utils import (
LRU,
TimeoutError,
_maybe_complex,
deprecated,
get_ip,
has_arg,
import_file,
iscoroutinefunction,
json_load_robust,
key_split,
log_errors,
offload,
parse_bytes,
parse_ports,
parse_timedelta,
silence_logging,
thread_state,
typename,
warn_on_duration,
)
from .utils_comm import gather_from_workers, pack_data, retry_operation
from .utils_perf import ThrottledGC, disable_gc_diagnosis, enable_gc_diagnosis
from .versions import get_versions
logger = logging.getLogger(__name__)
LOG_PDB = dask.config.get("distributed.admin.pdb-on-err")
no_value = "--no-value-sentinel--"
IN_PLAY = ("waiting", "ready", "executing", "long-running")
PENDING = ("waiting", "ready", "constrained")
PROCESSING = ("waiting", "ready", "constrained", "executing", "long-running")
READY = ("ready", "constrained")
DEFAULT_EXTENSIONS = [PubSubWorkerExtension]
DEFAULT_METRICS = {}
DEFAULT_STARTUP_INFORMATION = {}
DEFAULT_DATA_SIZE = parse_bytes(
dask.config.get("distributed.scheduler.default-data-size")
)
SerializedTask = namedtuple("SerializedTask", ["function", "args", "kwargs", "task"])
class TaskState:
"""Holds volatile state relating to an individual Dask task
* **dependencies**: ``set(TaskState instances)``
The data needed by this key to run
* **dependents**: ``set(TaskState instances)``
The keys that use this dependency. Only keys which are not available
already are tracked in this structure and dependents made available are
actively removed. Only after all dependents have been removed, this task
is allowed to be forgotten
* **duration**: ``float``
Expected duration the a task
* **priority**: ``tuple``
The priority this task given by the scheduler. Determines run order.
* **state**: ``str``
The current state of the task. One of ["waiting", "ready", "executing",
"fetch", "memory", "flight", "long-running", "rescheduled", "error"]
* **who_has**: ``set(worker)``
Workers that we believe have this data
* **coming_from**: ``str``
The worker that current task data is coming from if task is in flight
* **waiting_for_data**: ``set(keys of dependencies)``
A dynamic version of dependencies. All dependencies that we still don't
have for a particular key.
* **resource_restrictions**: ``{str: number}``
Abstract resources required to run a task
* **exception**: ``str``
The exception caused by running a task if it erred
* **traceback**: ``str``
The exception caused by running a task if it erred
* **type**: ``type``
The type of a particular piece of data
* **suspicious_count**: ``int``
The number of times a dependency has not been where we expected it
* **startstops**: ``[{startstop}]``
Log of transfer, load, and compute times for a task
* **start_time**: ``float``
Time at which task begins running
* **stop_time**: ``float``
Time at which task finishes running
* **metadata**: ``dict``
Metadata related to task. Stored metadata should be msgpack
serializable (e.g. int, string, list, dict).
* **nbytes**: ``int``
The size of a particular piece of data
* **annotations**: ``dict``
Task annotations
Parameters
----------
key: str
runspec: SerializedTask
A named tuple containing the ``function``, ``args``, ``kwargs`` and
``task`` associated with this `TaskState` instance. This defaults to
``None`` and can remain empty if it is a dependency that this worker
will receive from another worker.
"""
def __init__(self, key, runspec=None):
assert key is not None
self.key = key
self.runspec = runspec
self.dependencies = set()
self.dependents = set()
self.duration = None
self.priority = None
self.state = "new"
self.who_has = set()
self.coming_from = None
self.waiting_for_data = set()
self.resource_restrictions = None
self.exception = None
self.traceback = None
self.type = None
self.suspicious_count = 0
self.startstops = list()
self.start_time = None
self.stop_time = None
self.metadata = {}
self.nbytes = None
self.annotations = None
self.scheduler_holds_ref = False
def __repr__(self):
return "<Task %r %s>" % (self.key, self.state)
def get_nbytes(self) -> int:
nbytes = self.nbytes
return nbytes if nbytes is not None else DEFAULT_DATA_SIZE
[docs]class Worker(ServerNode):
"""Worker node in a Dask distributed cluster
Workers perform two functions:
1. **Serve data** from a local dictionary
2. **Perform computation** on that data and on data from peers
Workers keep the scheduler informed of their data and use that scheduler to
gather data from other workers when necessary to perform a computation.
You can start a worker with the ``dask-worker`` command line application::
$ dask-worker scheduler-ip:port
Use the ``--help`` flag to see more options::
$ dask-worker --help
The rest of this docstring is about the internal state the the worker uses
to manage and track internal computations.
**State**
**Informational State**
These attributes don't change significantly during execution.
* **nthreads:** ``int``:
Number of nthreads used by this worker process
* **executors:** ``Dict[str, concurrent.futures.Executor]``:
Executors used to perform computation. Always contains the default
executor.
* **local_directory:** ``path``:
Path on local machine to store temporary files
* **scheduler:** ``rpc``:
Location of scheduler. See ``.ip/.port`` attributes.
* **name:** ``string``:
Alias
* **services:** ``{str: Server}``:
Auxiliary web servers running on this worker
* **service_ports:** ``{str: port}``:
* **total_out_connections**: ``int``
The maximum number of concurrent outgoing requests for data
* **total_in_connections**: ``int``
The maximum number of concurrent incoming requests for data
* **total_comm_nbytes**: ``int``
* **batched_stream**: ``BatchedSend``
A batched stream along which we communicate to the scheduler
* **log**: ``[(message)]``
A structured and queryable log. See ``Worker.story``
**Volatile State**
These attributes track the progress of tasks that this worker is trying to
complete. In the descriptions below a ``key`` is the name of a task that
we want to compute and ``dep`` is the name of a piece of dependent data
that we want to collect from others.
* **tasks**: ``{key: TaskState}``
The tasks currently executing on this worker (and any dependencies of those tasks)
* **data:** ``{key: object}``:
Prefer using the **host** attribute instead of this, unless
memory_limit and at least one of memory_target_fraction or
memory_spill_fraction values are defined, in that case, this attribute
is a zict.Buffer, from which information on LRU cache can be queried.
* **data.memory:** ``{key: object}``:
Dictionary mapping keys to actual values stored in memory. Only
available if condition for **data** being a zict.Buffer is met.
* **data.disk:** ``{key: object}``:
Dictionary mapping keys to actual values stored on disk. Only
available if condition for **data** being a zict.Buffer is met.
* **data_needed**: deque(keys)
The keys which still require data in order to execute, arranged in a deque
* **ready**: [keys]
Keys that are ready to run. Stored in a LIFO stack
* **constrained**: [keys]
Keys for which we have the data to run, but are waiting on abstract
resources like GPUs. Stored in a FIFO deque
* **executing_count**: ``int``
A count of tasks currently executing on this worker
* **executed_count**: int
A number of tasks that this worker has run in its lifetime
* **long_running**: {keys}
A set of keys of tasks that are running and have started their own
long-running clients.
* **has_what**: ``{worker: {deps}}``
The data that we care about that we think a worker has
* **pending_data_per_worker**: ``{worker: [dep]}``
The data on each worker that we still want, prioritized as a deque
* **in_flight_tasks**: ``int``
A count of the number of tasks that are coming to us in current
peer-to-peer connections
* **in_flight_workers**: ``{worker: {task}}``
The workers from which we are currently gathering data and the
dependencies we expect from those connections
* **comm_bytes**: ``int``
The total number of bytes in flight
* **threads**: ``{key: int}``
The ID of the thread on which the task ran
* **active_threads**: ``{int: key}``
The keys currently running on active threads
* **waiting_for_data_count**: ``int``
A count of how many tasks are currently waiting for data
Parameters
----------
scheduler_ip: str
scheduler_port: int
ip: str, optional
data: MutableMapping, type, None
The object to use for storage, builds a disk-backed LRU dict by default
nthreads: int, optional
loop: tornado.ioloop.IOLoop
local_directory: str, optional
Directory where we place local resources
name: str, optional
memory_limit: int, float, string
Number of bytes of memory that this worker should use.
Set to zero for no limit. Set to 'auto' to calculate
as system.MEMORY_LIMIT * min(1, nthreads / total_cores)
Use strings or numbers like 5GB or 5e9
memory_target_fraction: float
Fraction of memory to try to stay beneath
memory_spill_fraction: float
Fraction of memory at which we start spilling to disk
memory_pause_fraction: float
Fraction of memory at which we stop running new tasks
executor: concurrent.futures.Executor, dict[str, concurrent.futures.Executor], str
The executor(s) to use. Depending on the type, it has the following meanings:
- Executor instance: The default executor.
- Dict[str, Executor]: mapping names to Executor instances. If the
"default" key isn't in the dict, a "default" executor will be created
using ``ThreadPoolExecutor(nthreads)``.
- Str: The string "offload", which refer to the same thread pool used for
offloading communications. This results in the same thread being used
for deserialization and computation.
resources: dict
Resources that this worker has like ``{'GPU': 2}``
nanny: str
Address on which to contact nanny, if it exists
lifetime: str
Amount of time like "1 hour" after which we gracefully shut down the worker.
This defaults to None, meaning no explicit shutdown time.
lifetime_stagger: str
Amount of time like "5 minutes" to stagger the lifetime value
The actual lifetime will be selected uniformly at random between
lifetime +/- lifetime_stagger
lifetime_restart: bool
Whether or not to restart a worker after it has reached its lifetime
Default False
Examples
--------
Use the command line to start a worker::
$ dask-scheduler
Start scheduler at 127.0.0.1:8786
$ dask-worker 127.0.0.1:8786
Start worker at: 127.0.0.1:1234
Registered with scheduler at: 127.0.0.1:8786
See Also
--------
distributed.scheduler.Scheduler
distributed.nanny.Nanny
"""
_instances = weakref.WeakSet()
_initialized_clients = weakref.WeakSet()
def __init__(
self,
scheduler_ip=None,
scheduler_port=None,
scheduler_file=None,
ncores=None,
nthreads=None,
loop=None,
local_dir=None,
local_directory=None,
services=None,
service_ports=None,
service_kwargs=None,
name=None,
reconnect=True,
memory_limit="auto",
executor=None,
resources=None,
silence_logs=None,
death_timeout=None,
preload=None,
preload_argv=None,
security=None,
contact_address=None,
memory_monitor_interval="200ms",
extensions=None,
metrics=DEFAULT_METRICS,
startup_information=DEFAULT_STARTUP_INFORMATION,
data=None,
interface=None,
host=None,
port=None,
protocol=None,
dashboard_address=None,
dashboard=False,
http_prefix="/",
nanny=None,
plugins=(),
low_level_profiler=dask.config.get("distributed.worker.profile.low-level"),
validate=None,
profile_cycle_interval=None,
lifetime=None,
lifetime_stagger=None,
lifetime_restart=None,
**kwargs,
):
self.tasks = dict()
self.waiting_for_data_count = 0
self.has_what = defaultdict(set)
self.pending_data_per_worker = defaultdict(deque)
self.nanny = nanny
self._lock = threading.Lock()
self.data_needed = deque() # TODO: replace with heap?
self.in_flight_tasks = 0
self.in_flight_workers = dict()
self.total_out_connections = dask.config.get(
"distributed.worker.connections.outgoing"
)
self.total_in_connections = dask.config.get(
"distributed.worker.connections.incoming"
)
self.total_comm_nbytes = 10e6
self.comm_nbytes = 0
self._missing_dep_flight = set()
self.threads = dict()
self.active_threads_lock = threading.Lock()
self.active_threads = dict()
self.profile_keys = defaultdict(profile.create)
self.profile_keys_history = deque(maxlen=3600)
self.profile_recent = profile.create()
self.profile_history = deque(maxlen=3600)
self.generation = 0
self.ready = list()
self.constrained = deque()
self.executing_count = 0
self.executed_count = 0
self.long_running = set()
self.recent_messages_log = deque(
maxlen=dask.config.get("distributed.comm.recent-messages-log-length")
)
self.target_message_size = 50e6 # 50 MB
self.log = deque(maxlen=100000)
if validate is None:
validate = dask.config.get("distributed.scheduler.validate")
self.validate = validate
self._transitions = {
# Basic state transitions
("new", "waiting"): self.transition_new_waiting,
("new", "fetch"): self.transition_new_fetch,
("waiting", "ready"): self.transition_waiting_ready,
("fetch", "flight"): self.transition_fetch_flight,
("ready", "executing"): self.transition_ready_executing,
("executing", "memory"): self.transition_executing_done,
("flight", "memory"): self.transition_flight_memory,
("flight", "fetch"): self.transition_flight_fetch,
# Shouldn't be a valid transition but happens nonetheless
("ready", "memory"): self.transition_ready_memory,
# Scheduler intercession (re-assignment)
("fetch", "waiting"): self.transition_fetch_waiting,
("flight", "waiting"): self.transition_flight_waiting,
# Errors, long-running, constrained
("waiting", "error"): self.transition_waiting_done,
("constrained", "executing"): self.transition_constrained_executing,
("executing", "error"): self.transition_executing_done,
("executing", "rescheduled"): self.transition_executing_done,
("executing", "long-running"): self.transition_executing_long_running,
("long-running", "error"): self.transition_executing_done,
("long-running", "memory"): self.transition_executing_done,
("long-running", "rescheduled"): self.transition_executing_done,
}
self.incoming_transfer_log = deque(maxlen=100000)
self.incoming_count = 0
self.outgoing_transfer_log = deque(maxlen=100000)
self.outgoing_count = 0
self.outgoing_current_count = 0
self.repetitively_busy = 0
self.bandwidth = parse_bytes(dask.config.get("distributed.scheduler.bandwidth"))
self.bandwidth_workers = defaultdict(
lambda: (0, 0)
) # bw/count recent transfers
self.bandwidth_types = defaultdict(lambda: (0, 0)) # bw/count recent transfers
self.latency = 0.001
self._client = None
if profile_cycle_interval is None:
profile_cycle_interval = dask.config.get("distributed.worker.profile.cycle")
profile_cycle_interval = parse_timedelta(profile_cycle_interval, default="ms")
self._setup_logging(logger)
if scheduler_file:
cfg = json_load_robust(scheduler_file)
scheduler_addr = cfg["address"]
elif scheduler_ip is None and dask.config.get("scheduler-address", None):
scheduler_addr = dask.config.get("scheduler-address")
elif scheduler_port is None:
scheduler_addr = coerce_to_address(scheduler_ip)
else:
scheduler_addr = coerce_to_address((scheduler_ip, scheduler_port))
self.contact_address = contact_address
if protocol is None:
protocol_address = scheduler_addr.split("://")
if len(protocol_address) == 2:
protocol = protocol_address[0]
# Target interface on which we contact the scheduler by default
# TODO: it is unfortunate that we special-case inproc here
if not host and not interface and not scheduler_addr.startswith("inproc://"):
host = get_ip(get_address_host(scheduler_addr))
self._start_port = port
self._start_host = host
self._interface = interface
self._protocol = protocol
if ncores is not None:
warnings.warn("the ncores= parameter has moved to nthreads=")
nthreads = ncores
self.nthreads = nthreads or CPU_COUNT
if resources is None:
resources = dask.config.get("distributed.worker.resources", None)
self.total_resources = resources or {}
self.available_resources = (resources or {}).copy()
self.death_timeout = parse_timedelta(death_timeout)
self.extensions = dict()
if silence_logs:
silence_logging(level=silence_logs)
if local_dir is not None:
warnings.warn("The local_dir keyword has moved to local_directory")
local_directory = local_dir
if not local_directory:
local_directory = dask.config.get("temporary-directory") or os.getcwd()
os.makedirs(local_directory, exist_ok=True)
local_directory = os.path.join(local_directory, "dask-worker-space")
with warn_on_duration(
"1s",
"Creating scratch directories is taking a surprisingly long time. "
"This is often due to running workers on a network file system. "
"Consider specifying a local-directory to point workers to write "
"scratch data to a local disk.",
):
self._workspace = WorkSpace(os.path.abspath(local_directory))
self._workdir = self._workspace.new_work_dir(prefix="worker-")
self.local_directory = self._workdir.dir_path
if preload is None:
preload = dask.config.get("distributed.worker.preload")
if preload_argv is None:
preload_argv = dask.config.get("distributed.worker.preload-argv")
self.preloads = preloading.process_preloads(
self, preload, preload_argv, file_dir=self.local_directory
)
if isinstance(security, dict):
security = Security(**security)
self.security = security or Security()
assert isinstance(self.security, Security)
self.connection_args = self.security.get_connection_args("worker")
self.memory_limit = parse_memory_limit(memory_limit, self.nthreads)
self.paused = False
if "memory_target_fraction" in kwargs:
self.memory_target_fraction = kwargs.pop("memory_target_fraction")
else:
self.memory_target_fraction = dask.config.get(
"distributed.worker.memory.target"
)
if "memory_spill_fraction" in kwargs:
self.memory_spill_fraction = kwargs.pop("memory_spill_fraction")
else:
self.memory_spill_fraction = dask.config.get(
"distributed.worker.memory.spill"
)
if "memory_pause_fraction" in kwargs:
self.memory_pause_fraction = kwargs.pop("memory_pause_fraction")
else:
self.memory_pause_fraction = dask.config.get(
"distributed.worker.memory.pause"
)
if isinstance(data, MutableMapping):
self.data = data
elif callable(data):
self.data = data()
elif isinstance(data, tuple):
self.data = data[0](**data[1])
elif self.memory_limit and (
self.memory_target_fraction or self.memory_spill_fraction
):
from .spill import SpillBuffer
self.data = SpillBuffer(
os.path.join(self.local_directory, "storage"),
target=int(
self.memory_limit
* (self.memory_target_fraction or self.memory_spill_fraction)
)
or sys.maxsize,
)
else:
self.data = dict()
self.actors = {}
self.loop = loop or IOLoop.current()
self.reconnect = reconnect
# Common executors always available
self.executors: Dict[str, concurrent.futures.Executor] = {
"offload": utils._offload_executor,
"actor": ThreadPoolExecutor(1, thread_name_prefix="Dask-Actor-Threads"),
}
# Find the default executor
if executor == "offload":
self.executors["default"] = self.executors["offload"]
elif isinstance(executor, dict):
self.executors.update(executor)
elif executor is not None:
self.executors["default"] = executor
if "default" not in self.executors:
self.executors["default"] = ThreadPoolExecutor(
self.nthreads, thread_name_prefix="Dask-Default-Threads"
)
self.batched_stream = BatchedSend(interval="2ms", loop=self.loop)
self.name = name
self.scheduler_delay = 0
self.stream_comms = dict()
self.heartbeat_active = False
self._ipython_kernel = None
if self.local_directory not in sys.path:
sys.path.insert(0, self.local_directory)
self.services = {}
self.service_specs = services or {}
self._dashboard_address = dashboard_address
self._dashboard = dashboard
self._http_prefix = http_prefix
self.metrics = dict(metrics) if metrics else {}
self.startup_information = (
dict(startup_information) if startup_information else {}
)
self.low_level_profiler = low_level_profiler
handlers = {
"gather": self.gather,
"run": self.run,
"run_coroutine": self.run_coroutine,
"get_data": self.get_data,
"update_data": self.update_data,
"free_keys": self.handle_free_keys,
"terminate": self.close,
"ping": pingpong,
"upload_file": self.upload_file,
"start_ipython": self.start_ipython,
"call_stack": self.get_call_stack,
"profile": self.get_profile,
"profile_metadata": self.get_profile_metadata,
"get_logs": self.get_logs,
"keys": self.keys,
"versions": self.versions,
"actor_execute": self.actor_execute,
"actor_attribute": self.actor_attribute,
"plugin-add": self.plugin_add,
"plugin-remove": self.plugin_remove,
"get_monitor_info": self.get_monitor_info,
}
stream_handlers = {
"close": self.close,
"compute-task": self.add_task,
"free-keys": self.handle_free_keys,
"superfluous-data": self.handle_superfluous_data,
"steal-request": self.steal_request,
}
super().__init__(
handlers=handlers,
stream_handlers=stream_handlers,
io_loop=self.loop,
connection_args=self.connection_args,
**kwargs,
)
self.scheduler = self.rpc(scheduler_addr)
self.execution_state = {
"scheduler": self.scheduler.address,
"ioloop": self.loop,
"worker": self,
}
pc = PeriodicCallback(self.heartbeat, 1000)
self.periodic_callbacks["heartbeat"] = pc
pc = PeriodicCallback(
lambda: self.batched_stream.send({"op": "keep-alive"}), 60000
)
self.periodic_callbacks["keep-alive"] = pc
self._address = contact_address
self.memory_monitor_interval = parse_timedelta(
memory_monitor_interval, default="ms"
)
if self.memory_limit:
self._memory_monitoring = False
pc = PeriodicCallback(
self.memory_monitor, self.memory_monitor_interval * 1000
)
self.periodic_callbacks["memory"] = pc
if extensions is None:
extensions = DEFAULT_EXTENSIONS
for ext in extensions:
ext(self)
self._throttled_gc = ThrottledGC(logger=logger)
setproctitle("dask-worker [not started]")
profile_trigger_interval = parse_timedelta(
dask.config.get("distributed.worker.profile.interval"), default="ms"
)
pc = PeriodicCallback(self.trigger_profile, profile_trigger_interval * 1000)
self.periodic_callbacks["profile"] = pc
pc = PeriodicCallback(self.cycle_profile, profile_cycle_interval * 1000)
self.periodic_callbacks["profile-cycle"] = pc
self.plugins = {}
self._pending_plugins = plugins
self.lifetime = lifetime or dask.config.get(
"distributed.worker.lifetime.duration"
)
lifetime_stagger = lifetime_stagger or dask.config.get(
"distributed.worker.lifetime.stagger"
)
self.lifetime_restart = lifetime_restart or dask.config.get(
"distributed.worker.lifetime.restart"
)
if isinstance(self.lifetime, str):
self.lifetime = parse_timedelta(self.lifetime)
if isinstance(lifetime_stagger, str):
lifetime_stagger = parse_timedelta(lifetime_stagger)
if self.lifetime:
self.lifetime += (random.random() * 2 - 1) * lifetime_stagger
self.io_loop.call_later(self.lifetime, self.close_gracefully)
Worker._instances.add(self)
##################
# Administrative #
##################
def __repr__(self):
return "<%s: %r, %s, %s, stored: %d, running: %d/%d, ready: %d, comm: %d, waiting: %d>" % (
self.__class__.__name__,
self.address,
self.name,
self.status,
len(self.data),
self.executing_count,
self.nthreads,
len(self.ready),
self.in_flight_tasks,
self.waiting_for_data_count,
)
@property
def logs(self):
return self._deque_handler.deque
def log_event(self, topic, msg):
self.batched_stream.send(
{
"op": "log-event",
"topic": topic,
"msg": msg,
}
)
@property
def worker_address(self):
"""For API compatibility with Nanny"""
return self.address
@property
def local_dir(self):
"""For API compatibility with Nanny"""
warnings.warn(
"The local_dir attribute has moved to local_directory", stacklevel=2
)
return self.local_directory
@property
def executor(self):
return self.executors["default"]
async def get_metrics(self):
out = dict(
executing=self.executing_count,
in_memory=len(self.data),
ready=len(self.ready),
in_flight=self.in_flight_tasks,
bandwidth={
"total": self.bandwidth,
"workers": dict(self.bandwidth_workers),
"types": keymap(typename, self.bandwidth_types),
},
spilled_nbytes=getattr(self.data, "spilled_total", 0),
)
out.update(self.monitor.recent())
for k, metric in self.metrics.items():
try:
result = metric(self)
if isawaitable(result):
result = await result
# In case of collision, prefer core metrics
out.setdefault(k, result)
except Exception: # TODO: log error once
pass
return out
async def get_startup_information(self):
result = {}
for k, f in self.startup_information.items():
try:
v = f(self)
if isawaitable(v):
v = await v
result[k] = v
except Exception: # TODO: log error once
pass
return result
def identity(self, comm=None):
return {
"type": type(self).__name__,
"id": self.id,
"scheduler": self.scheduler.address,
"nthreads": self.nthreads,
"ncores": self.nthreads, # backwards compatibility
"memory_limit": self.memory_limit,
}
#####################
# External Services #
#####################
async def _register_with_scheduler(self):
self.periodic_callbacks["keep-alive"].stop()
self.periodic_callbacks["heartbeat"].stop()
start = time()
if self.contact_address is None:
self.contact_address = self.address
logger.info("-" * 49)
while True:
try:
_start = time()
comm = await connect(self.scheduler.address, **self.connection_args)
comm.name = "Worker->Scheduler"
comm._server = weakref.ref(self)
await comm.write(
dict(
op="register-worker",
reply=False,
address=self.contact_address,
keys=list(self.data),
nthreads=self.nthreads,
name=self.name,
nbytes={ts.key: ts.get_nbytes() for ts in self.tasks.values()},
types={k: typename(v) for k, v in self.data.items()},
now=time(),
resources=self.total_resources,
memory_limit=self.memory_limit,
local_directory=self.local_directory,
services=self.service_ports,
nanny=self.nanny,
pid=os.getpid(),
versions=get_versions(),
metrics=await self.get_metrics(),
extra=await self.get_startup_information(),
),
serializers=["msgpack"],
)
future = comm.read(deserializers=["msgpack"])
response = await future
if response.get("warning"):
logger.warning(response["warning"])
_end = time()
middle = (_start + _end) / 2
self._update_latency(_end - start)
self.scheduler_delay = response["time"] - middle
self.status = Status.running
break
except EnvironmentError:
logger.info("Waiting to connect to: %26s", self.scheduler.address)
await asyncio.sleep(0.1)
except TimeoutError:
logger.info("Timed out when connecting to scheduler")
if response["status"] != "OK":
raise ValueError("Unexpected response from register: %r" % (response,))
else:
await asyncio.gather(
*[
self.plugin_add(name=name, plugin=plugin)
for name, plugin in response["worker-plugins"].items()
]
)
logger.info(" Registered to: %26s", self.scheduler.address)
logger.info("-" * 49)
self.batched_stream.start(comm)
self.periodic_callbacks["keep-alive"].start()
self.periodic_callbacks["heartbeat"].start()
self.loop.add_callback(self.handle_scheduler, comm)
def _update_latency(self, latency):
self.latency = latency * 0.05 + self.latency * 0.95
if self.digests is not None:
self.digests["latency"].add(latency)
async def heartbeat(self):
if self.heartbeat_active:
logger.debug("Heartbeat skipped: channel busy")
return
self.heartbeat_active = True
logger.debug("Heartbeat: %s", self.address)
try:
start = time()
with self.active_threads_lock:
active_keys = list(self.active_threads.values())
response = await retry_operation(
self.scheduler.heartbeat_worker,
address=self.contact_address,
now=start,
metrics=await self.get_metrics(),
executing={
key: start - self.tasks[key].start_time
for key in active_keys
if key in self.tasks
},
)
end = time()
middle = (start + end) / 2
self._update_latency(end - start)
if response["status"] == "missing":
for i in range(10):
if self.status != Status.running:
break
else:
await asyncio.sleep(0.05)
else:
await self._register_with_scheduler()
return
self.scheduler_delay = response["time"] - middle
self.periodic_callbacks["heartbeat"].callback_time = (
response["heartbeat-interval"] * 1000
)
self.bandwidth_workers.clear()
self.bandwidth_types.clear()
except CommClosedError:
logger.warning("Heartbeat to scheduler failed")
if not self.reconnect:
await self.close(report=False)
except IOError as e:
# Scheduler is gone. Respect distributed.comm.timeouts.connect
if "Timed out trying to connect" in str(e):
await self.close(report=False)
else:
raise e
finally:
self.heartbeat_active = False
async def handle_scheduler(self, comm):
try:
await self.handle_stream(
comm, every_cycle=[self.ensure_communicating, self.ensure_computing]
)
except Exception as e:
logger.exception(e)
raise
finally:
if self.reconnect and self.status == Status.running:
logger.info("Connection to scheduler broken. Reconnecting...")
self.loop.add_callback(self.heartbeat)
else:
await self.close(report=False)
[docs] def start_ipython(self, comm):
"""Start an IPython kernel
Returns Jupyter connection info dictionary.
"""
from ._ipython_utils import start_ipython
if self._ipython_kernel is None:
self._ipython_kernel = start_ipython(
ip=self.ip, ns={"worker": self}, log=logger
)
return self._ipython_kernel.get_connection_info()
async def upload_file(self, comm, filename=None, data=None, load=True):
out_filename = os.path.join(self.local_directory, filename)
def func(data):
if isinstance(data, str):
data = data.encode()
with open(out_filename, "wb") as f:
f.write(data)
f.flush()
return data
if len(data) < 10000:
data = func(data)
else:
data = await offload(func, data)
if load:
try:
import_file(out_filename)
cache_loads.data.clear()
except Exception as e:
logger.exception(e)
raise e
return {"status": "OK", "nbytes": len(data)}
def keys(self, comm=None):
return list(self.data)
async def gather(self, comm=None, who_has=None):
who_has = {
k: [coerce_to_address(addr) for addr in v]
for k, v in who_has.items()
if k not in self.data
}
result, missing_keys, missing_workers = await gather_from_workers(
who_has, rpc=self.rpc, who=self.address
)
if missing_keys:
logger.warning(
"Could not find data: %s on workers: %s (who_has: %s)",
missing_keys,
missing_workers,
who_has,
)
return {"status": "missing-data", "keys": missing_keys}
else:
self.update_data(data=result, report=False)
return {"status": "OK"}
def get_monitor_info(self, comm=None, recent=False, start=0):
result = dict(
range_query=(
self.monitor.recent()
if recent
else self.monitor.range_query(start=start)
),
count=self.monitor.count,
last_time=self.monitor.last_time,
)
if nvml.device_get_count() > 0:
result["gpu_name"] = self.monitor.gpu_name
result["gpu_memory_total"] = self.monitor.gpu_memory_total
return result
#############
# Lifecycle #
#############
async def start(self):
if self.status and self.status in (
Status.closed,
Status.closing,
Status.closing_gracefully,
):
return
assert self.status is Status.undefined, self.status
await super().start()
enable_gc_diagnosis()
thread_state.on_event_loop_thread = True
ports = parse_ports(self._start_port)
for port in ports:
start_address = address_from_user_args(
host=self._start_host,
port=port,
interface=self._interface,
protocol=self._protocol,
security=self.security,
)
try:
await self.listen(
start_address, **self.security.get_listen_args("worker")
)
except OSError as e:
if len(ports) > 1 and e.errno == errno.EADDRINUSE:
continue
else:
raise e
else:
self._start_address = start_address
break
else:
raise ValueError(
f"Could not start Worker on host {self._start_host}"
f"with port {self._start_port}"
)
# Start HTTP server associated with this Worker node
routes = get_handlers(
server=self,
modules=dask.config.get("distributed.worker.http.routes"),
prefix=self._http_prefix,
)
self.start_http_server(routes, self._dashboard_address)
if self._dashboard:
try:
import distributed.dashboard.worker
except ImportError:
logger.debug("To start diagnostics web server please install Bokeh")
else:
distributed.dashboard.worker.connect(
self.http_application,
self.http_server,
self,
prefix=self._http_prefix,
)
self.ip = get_address_host(self.address)
if self.name is None:
self.name = self.address
for preload in self.preloads:
await preload.start()
# Services listen on all addresses
# Note Nanny is not a "real" service, just some metadata
# passed in service_ports...
self.start_services(self.ip)
try:
listening_address = "%s%s:%d" % (self.listener.prefix, self.ip, self.port)
except Exception:
listening_address = "%s%s" % (self.listener.prefix, self.ip)
logger.info(" Start worker at: %26s", self.address)
logger.info(" Listening to: %26s", listening_address)
for k, v in self.service_ports.items():
logger.info(" %16s at: %26s" % (k, self.ip + ":" + str(v)))
logger.info("Waiting to connect to: %26s", self.scheduler.address)
logger.info("-" * 49)
logger.info(" Threads: %26d", self.nthreads)
if self.memory_limit:
logger.info(" Memory: %26s", format_bytes(self.memory_limit))
logger.info(" Local Directory: %26s", self.local_directory)
setproctitle("dask-worker [%s]" % self.address)
await asyncio.gather(
*[self.plugin_add(plugin=plugin) for plugin in self._pending_plugins]
)
self._pending_plugins = ()
await self._register_with_scheduler()
self.start_periodic_callbacks()
return self
def _close(self, *args, **kwargs):
warnings.warn("Worker._close has moved to Worker.close", stacklevel=2)
return self.close(*args, **kwargs)
async def close(
self, report=True, timeout=10, nanny=True, executor_wait=True, safe=False
):
with log_errors():
if self.status in (Status.closed, Status.closing):
await self.finished()
return
self.reconnect = False
disable_gc_diagnosis()
try:
logger.info("Stopping worker at %s", self.address)
except ValueError: # address not available if already closed
logger.info("Stopping worker")
if self.status not in (Status.running, Status.closing_gracefully):
logger.info("Closed worker has not yet started: %s", self.status)
self.status = Status.closing
for preload in self.preloads:
await preload.teardown()
if nanny and self.nanny:
with self.rpc(self.nanny) as r:
await r.close_gracefully()
setproctitle("dask-worker [closing]")
teardowns = [
plugin.teardown(self)
for plugin in self.plugins.values()
if hasattr(plugin, "teardown")
]
await asyncio.gather(*[td for td in teardowns if isawaitable(td)])
for pc in self.periodic_callbacks.values():
pc.stop()
if self._client:
# If this worker is the last one alive, clean up the worker
# initialized clients
if not any(
w
for w in Worker._instances
if w != self and w.status == Status.running
):
for c in Worker._initialized_clients:
# Regardless of what the client was initialized with
# we'll require the result as a future. This is
# necessary since the heursitics of asynchronous are not
# reliable and we might deadlock here
c._asynchronous = True
if c.asynchronous:
await c.close()
else:
# There is still the chance that even with us
# telling the client to be async, itself will decide
# otherwise
c.close()
with suppress(EnvironmentError, TimeoutError):
if report and self.contact_address is not None:
await asyncio.wait_for(
self.scheduler.unregister(
address=self.contact_address, safe=safe
),
timeout,
)
await self.scheduler.close_rpc()
self._workdir.release()
self.stop_services()
if (
self.batched_stream
and self.batched_stream.comm
and not self.batched_stream.comm.closed()
):
self.batched_stream.send({"op": "close-stream"})
if self.batched_stream:
with suppress(TimeoutError):
await self.batched_stream.close(timedelta(seconds=timeout))
for executor in self.executors.values():
if executor is utils._offload_executor:
continue # Never shutdown the offload executor
if isinstance(executor, ThreadPoolExecutor):
executor._work_queue.queue.clear()
executor.shutdown(wait=executor_wait, timeout=timeout)
else:
executor.shutdown(wait=executor_wait)
self.stop()
await self.rpc.close()
self.status = Status.closed
await ServerNode.close(self)
setproctitle("dask-worker [closed]")
return "OK"
[docs] async def close_gracefully(self, restart=None):
"""Gracefully shut down a worker
This first informs the scheduler that we're shutting down, and asks it
to move our data elsewhere. Afterwards, we close as normal
"""
if self.status in (Status.closing, Status.closing_gracefully):
await self.finished()
if self.status == Status.closed:
return
if restart is None:
restart = self.lifetime_restart
logger.info("Closing worker gracefully: %s", self.address)
self.status = Status.closing_gracefully
await self.scheduler.retire_workers(workers=[self.address], remove=False)
await self.close(safe=True, nanny=not restart)
async def terminate(self, comm=None, report=True, **kwargs):
await self.close(report=report, **kwargs)
return "OK"
async def wait_until_closed(self):
warnings.warn("wait_until_closed has moved to finished()")
await self.finished()
assert self.status == Status.closed
################
# Worker Peers #
################
def send_to_worker(self, address, msg):
if address not in self.stream_comms:
bcomm = BatchedSend(interval="1ms", loop=self.loop)
self.stream_comms[address] = bcomm
async def batched_send_connect():
comm = await connect(
address, **self.connection_args # TODO, serialization
)
comm.name = "Worker->Worker"
await comm.write({"op": "connection_stream"})
bcomm.start(comm)
self.loop.add_callback(batched_send_connect)
self.stream_comms[address].send(msg)
async def get_data(
self, comm, keys=None, who=None, serializers=None, max_connections=None
):
start = time()
if max_connections is None:
max_connections = self.total_in_connections
# Allow same-host connections more liberally
if (
max_connections
and comm
and get_address_host(comm.peer_address) == get_address_host(self.address)
):
max_connections = max_connections * 2
if self.paused:
max_connections = 1
throttle_msg = " Throttling outgoing connections because worker is paused."
else:
throttle_msg = ""
if (
max_connections is not False
and self.outgoing_current_count >= max_connections
):
logger.debug(
"Worker %s has too many open connections to respond to data request from %s (%d/%d).%s",
self.address,
who,
self.outgoing_current_count,
max_connections,
throttle_msg,
)
return {"status": "busy"}
self.outgoing_current_count += 1
data = {k: self.data[k] for k in keys if k in self.data}
if len(data) < len(keys):
for k in set(keys) - set(data):
if k in self.actors:
from .actor import Actor
data[k] = Actor(type(self.actors[k]), self.address, k)
msg = {"status": "OK", "data": {k: to_serialize(v) for k, v in data.items()}}
nbytes = {k: self.tasks[k].nbytes for k in data if k in self.tasks}
stop = time()
if self.digests is not None:
self.digests["get-data-load-duration"].add(stop - start)
start = time()
try:
compressed = await comm.write(msg, serializers=serializers)
response = await comm.read(deserializers=serializers)
assert response == "OK", response
except EnvironmentError:
logger.exception(
"failed during get data with %s -> %s", self.address, who, exc_info=True
)
comm.abort()
raise
finally:
self.outgoing_current_count -= 1
stop = time()
if self.digests is not None:
self.digests["get-data-send-duration"].add(stop - start)
total_bytes = sum(filter(None, nbytes.values()))
self.outgoing_count += 1
duration = (stop - start) or 0.5 # windows
self.outgoing_transfer_log.append(
{
"start": start + self.scheduler_delay,
"stop": stop + self.scheduler_delay,
"middle": (start + stop) / 2,
"duration": duration,
"who": who,
"keys": nbytes,
"total": total_bytes,
"compressed": compressed,
"bandwidth": total_bytes / duration,
}
)
return Status.dont_reply
###################
# Local Execution #
###################
def update_data(self, comm=None, data=None, report=True, serializers=None):
for key, value in data.items():
ts = self.tasks.get(key)
if getattr(ts, "state", None) is not None:
self.transition(ts, "memory", value=value)
else:
self.tasks[key] = ts = TaskState(key)
self.put_key_in_memory(ts, value)
ts.priority = None
ts.duration = None
ts.scheduler_holds_ref = True
self.log.append((key, "receive-from-scatter"))
if report:
self.log.append(
("Notifying scheduler about in-memory in update-data", list(data))
)
self.batched_stream.send({"op": "add-keys", "keys": list(data)})
info = {"nbytes": {k: sizeof(v) for k, v in data.items()}, "status": "OK"}
return info
[docs] def handle_free_keys(self, comm=None, keys=None, reason=None):
"""
Handler to be called by the scheduler.
The given keys are no longer referred to and required by the scheduler.
The worker is now allowed to release the key, if applicable.
This does not guarantee that the memory is released since the worker may
still decide to hold on to the data and task since it is required by an
upstream dependency.
"""
self.log.append(("free-keys", keys, reason))
for key in keys:
ts = self.tasks.get(key)
if ts:
ts.scheduler_holds_ref = False
self.release_key(key, report=False, reason=reason)
[docs] def handle_superfluous_data(self, keys=(), reason=None):
"""Stream handler notifying the worker that it might be holding unreferenced, superfluous data.
This should not actually happen during ordinary operations and is only
intended to correct any erroneous state. An example where this is
necessary is if a worker fetches data for a downstream task but that
task is released before the data arrives.
In this case, the scheduler will notify the worker that it may be
holding this unnecessary data, if the worker hasn't released the data itself, already.
This handler does not guarantee the task nor the data to be actually
released but only asks the worker to release the data on a best effort
guarantee. This protects from race conditions where the given keys may
already have been rescheduled for compute in which case the compute
would win and this handler is ignored.
For stronger guarantees, see handler free_keys
"""
self.log.append(("Handle superfluous data", keys, reason))
for key in list(keys):
ts = self.tasks.get(key)
if ts and not ts.scheduler_holds_ref:
self.release_key(key, reason=f"delete data: {reason}", report=False)
logger.debug("Worker %s -- Deleted %d keys", self.name, len(keys))
return "OK"
async def set_resources(self, **resources):
for r, quantity in resources.items():
if r in self.total_resources:
self.available_resources[r] += quantity - self.total_resources[r]
else:
self.available_resources[r] = quantity
self.total_resources[r] = quantity
await retry_operation(
self.scheduler.set_resources,
resources=self.total_resources,
worker=self.contact_address,
)
###################
# Task Management #
###################
def add_task(
self,
key,
function=None,
args=None,
kwargs=None,
task=no_value,
who_has=None,
nbytes=None,
priority=None,
duration=None,
resource_restrictions=None,
actor=False,
annotations=None,
**kwargs2,
):
try:
runspec = SerializedTask(function, args, kwargs, task)
if key in self.tasks:
ts = self.tasks[key]
ts.scheduler_holds_ref = True
if ts.state == "memory":
assert key in self.data or key in self.actors
logger.debug(
"Asked to compute pre-existing result: %s: %s", key, ts.state
)
self.send_task_state_to_scheduler(ts)
return
if ts.state in IN_PLAY:
return
if ts.state == "error":
ts.exception = None
ts.traceback = None
else:
# This is a scheduler re-assignment
# Either `fetch` -> `waiting` or `flight` -> `waiting`
self.log.append((ts.key, "re-adding key, new TaskState"))
self.transition(ts, "waiting", runspec=runspec)
else:
self.log.append((key, "new"))
self.tasks[key] = ts = TaskState(
key=key, runspec=SerializedTask(function, args, kwargs, task)
)
self.transition(ts, "waiting")
# TODO: move transition of `ts` to end of `add_task`
# This will require a chained recommendation transition system like
# the scheduler
if priority is not None:
priority = tuple(priority) + (self.generation,)
self.generation -= 1
if actor:
self.actors[ts.key] = None
ts.scheduler_holds_ref = True
ts.runspec = runspec
ts.priority = priority
ts.duration = duration
if resource_restrictions:
ts.resource_restrictions = resource_restrictions
ts.annotations = annotations
who_has = who_has or {}
for dependency, workers in who_has.items():
assert workers
if dependency not in self.tasks:
# initial state is "new"
# this dependency does not already exist on worker
self.tasks[dependency] = dep_ts = TaskState(key=dependency)
# link up to child / parents
ts.dependencies.add(dep_ts)
dep_ts.dependents.add(ts)
# check to ensure task wasn't already executed and partially released
# # TODO: make this less bad
state = "fetch" if dependency not in self.data else "memory"
# transition from new -> fetch handles adding dependency
# to waiting_for_data
discarded_self = False
if self.address in workers and state == "fetch":
discarded_self = True
workers = set(workers)
workers.discard(self.address)
who_has[dependency] = tuple(workers)
self.transition(dep_ts, state, who_has=workers)
self.log.append(
(
dependency,
"new-dep",
dep_ts.state,
f"requested by {ts.key}",
discarded_self,
)
)
else:
# task was already present on worker
dep_ts = self.tasks[dependency]
# link up to child / parents
ts.dependencies.add(dep_ts)
dep_ts.dependents.add(ts)
if dep_ts.state in ("fetch", "flight"):
# if we _need_ to grab data or are in the process
ts.waiting_for_data.add(dep_ts.key)
self.update_who_has(who_has=who_has)
if nbytes is not None:
for key, value in nbytes.items():
self.tasks[key].nbytes = value
if ts.waiting_for_data:
self.data_needed.append(ts.key)
else:
self.transition(ts, "ready")
if self.validate:
for worker, keys in self.has_what.items():
for k in keys:
assert worker in self.tasks[k].who_has
if who_has:
assert all(self.tasks[dep] in ts.dependencies for dep in who_has)
assert all(self.tasks[dep.key] for dep in ts.dependencies)
for dependency in ts.dependencies:
self.validate_task(dependency)
self.validate_task(ts)
except Exception as e:
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
def transition(self, ts, finish, **kwargs):
if ts is None:
return
start = ts.state
if start == finish:
return
func = self._transitions[start, finish]
self.log.append((ts.key, start, finish))
state = func(ts, **kwargs)
if state and finish != state:
self.log.append((ts.key, start, finish, state))
ts.state = state or finish
if self.validate:
self.validate_task(ts)
self._notify_plugins("transition", ts.key, start, state or finish, **kwargs)
def transition_new_waiting(self, ts):
try:
if self.validate:
assert ts.state == "new"
assert ts.runspec is not None
assert not ts.who_has
except Exception as e:
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
def transition_new_fetch(self, ts, who_has):
try:
if self.validate:
assert ts.state == "new"
assert ts.runspec is None
assert who_has
for dependent in ts.dependents:
dependent.waiting_for_data.add(ts.key)
ts.who_has.update(who_has)
for w in who_has:
self.has_what[w].add(ts.key)
self.pending_data_per_worker[w].append(ts.key)
except Exception as e:
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
[docs] def transition_fetch_waiting(self, ts, runspec):
"""This is a rescheduling transition that occurs after a worker failure.
A task was available from another worker but that worker died and the
scheduler reassigned the task for computation here.
"""
try:
if self.validate:
assert ts.state == "fetch"
assert ts.runspec is None
assert runspec is not None
ts.runspec = runspec
# remove any stale entries in `has_what`
for worker in self.has_what.keys():
self.has_what[worker].discard(ts.key)
# clear `who_has` of stale info
ts.who_has.clear()
# remove entry from dependents to avoid a spurious `gather_dep` call``
for dependent in ts.dependents:
dependent.waiting_for_data.discard(ts.key)
except Exception as e:
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
[docs] def transition_flight_waiting(self, ts, runspec):
"""This is a rescheduling transition that occurs after
a worker failure. A task was in flight from another worker to this
worker when that worker died and the scheduler reassigned the task for
computation here.
"""
try:
if self.validate:
assert ts.state == "flight"
assert ts.runspec is None
assert runspec is not None
ts.runspec = runspec
# remove any stale entries in `has_what`
for worker in self.has_what.keys():
self.has_what[worker].discard(ts.key)
# clear `who_has` of stale info
ts.who_has.clear()
# remove entry from dependents to avoid a spurious `gather_dep` call``
for dependent in ts.dependents:
dependent.waiting_for_data.discard(ts.key)
except Exception as e:
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
def transition_fetch_flight(self, ts, worker=None):
try:
if self.validate:
assert ts.state == "fetch"
assert ts.dependents
ts.coming_from = worker
self.in_flight_tasks += 1
except Exception as e:
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
def transition_flight_fetch(self, ts):
try:
if self.validate:
assert ts.state == "flight"
self.in_flight_tasks -= 1
ts.coming_from = None
ts.runspec = None
if not ts.who_has:
if ts.key not in self._missing_dep_flight:
self._missing_dep_flight.add(ts.key)
logger.info("Task %s does not know who has", ts)
self.loop.add_callback(self.handle_missing_dep, ts)
for w in ts.who_has:
self.pending_data_per_worker[w].append(ts.key)
for dependent in ts.dependents:
dependent.waiting_for_data.add(ts.key)
if dependent.state == "waiting":
self.data_needed.append(dependent.key)
except Exception as e:
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
def transition_flight_memory(self, ts, value=None):
try:
if self.validate:
assert ts.state == "flight"
self.in_flight_tasks -= 1
ts.coming_from = None
self.put_key_in_memory(ts, value)
for dependent in ts.dependents:
try:
dependent.waiting_for_data.remove(ts.key)
self.waiting_for_data_count -= 1
except KeyError:
pass
self.log.append(("Notifying scheduler about in-memory", ts.key))
self.batched_stream.send({"op": "add-keys", "keys": [ts.key]})
except Exception as e:
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
def transition_waiting_ready(self, ts):
try:
if self.validate:
assert ts.state == "waiting"
assert not ts.waiting_for_data
assert all(
dep.key in self.data or dep.key in self.actors
for dep in ts.dependencies
)
assert all(dep.state == "memory" for dep in ts.dependencies)
assert ts.key not in self.ready
self.has_what[self.address].discard(ts.key)
if ts.resource_restrictions is not None:
self.constrained.append(ts.key)
return "constrained"
else:
heapq.heappush(self.ready, (ts.priority, ts.key))
except Exception as e:
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
def transition_waiting_done(self, ts, value=None):
try:
if self.validate:
assert ts.state == "waiting"
assert ts.key not in self.ready
self.waiting_for_data_count -= len(ts.waiting_for_data)
ts.waiting_for_data.clear()
if value is not None:
self.put_key_in_memory(ts, value)
self.send_task_state_to_scheduler(ts)
except Exception as e:
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
def transition_ready_executing(self, ts):
try:
if self.validate:
assert not ts.waiting_for_data
assert ts.key not in self.data
assert ts.state in READY
assert ts.key not in self.ready
assert all(
dep.key in self.data or dep.key in self.actors
for dep in ts.dependencies
)
self.executing_count += 1
self.loop.add_callback(self.execute, ts.key)
except Exception as e:
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
def transition_ready_error(self, ts):
if self.validate:
assert ts.exception is not None
assert ts.traceback is not None
self.send_task_state_to_scheduler(ts)
def transition_ready_memory(self, ts, value=no_value):
if value is not no_value:
self.put_key_in_memory(ts, value=value)
self.send_task_state_to_scheduler(ts)
def transition_constrained_executing(self, ts):
self.transition_ready_executing(ts)
for resource, quantity in ts.resource_restrictions.items():
self.available_resources[resource] -= quantity
if self.validate:
assert all(v >= 0 for v in self.available_resources.values())
def transition_executing_done(self, ts, value=no_value, report=True):
try:
if self.validate:
assert ts.state == "executing" or ts.key in self.long_running
assert not ts.waiting_for_data
assert ts.key not in self.ready
out = None
if ts.resource_restrictions is not None:
for resource, quantity in ts.resource_restrictions.items():
self.available_resources[resource] += quantity
if ts.state == "executing":
self.executing_count -= 1
self.executed_count += 1
elif ts.state == "long-running":
self.long_running.remove(ts.key)
if value is not no_value:
try:
self.put_key_in_memory(ts, value, transition=False)
except Exception as e:
logger.info("Failed to put key in memory", exc_info=True)
msg = error_message(e)
ts.exception = msg["exception"]
ts.traceback = msg["traceback"]
ts.state = "error"
out = "error"
# Don't release the dependency keys, but do remove them from `dependents`
for dependency in ts.dependencies:
dependency.dependents.discard(ts)
ts.dependencies.clear()
if report and self.batched_stream and self.status == Status.running:
self.send_task_state_to_scheduler(ts)
else:
raise CommClosedError
return out
except EnvironmentError:
logger.info("Comm closed")
except Exception as e:
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
def transition_executing_long_running(self, ts, compute_duration=None):
try:
if self.validate:
assert ts.state == "executing"
self.executing_count -= 1
self.long_running.add(ts.key)
self.batched_stream.send(
{
"op": "long-running",
"key": ts.key,
"compute_duration": compute_duration,
}
)
self.io_loop.add_callback(self.ensure_computing)
except Exception as e:
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
def maybe_transition_long_running(self, ts, compute_duration=None):
if ts.state == "executing":
self.transition(ts, "long-running", compute_duration=compute_duration)
def stateof(self, key):
ts = self.tasks[key]
return {
"executing": ts.state == "executing",
"waiting_for_data": bool(ts.waiting_for_data),
"heap": key in pluck(1, self.ready),
"data": key in self.data,
}
def story(self, *keys):
keys = [key.key if isinstance(key, TaskState) else key for key in keys]
return [
msg
for msg in self.log
if any(key in msg for key in keys)
or any(
key in c
for key in keys
for c in msg
if isinstance(c, (tuple, list, set))
)
]
def ensure_communicating(self):
changed = True
try:
while (
changed
and self.data_needed
and len(self.in_flight_workers) < self.total_out_connections
):
changed = False
logger.debug(
"Ensure communicating. Pending: %d. Connections: %d/%d",
len(self.data_needed),
len(self.in_flight_workers),
self.total_out_connections,
)
key = self.data_needed[0]
if key not in self.tasks:
self.data_needed.popleft()
changed = True
continue
ts = self.tasks[key]
if ts.state != "waiting":
self.log.append((key, "communication pass"))
self.data_needed.popleft()
changed = True
continue
dependencies = ts.dependencies
if self.validate:
assert all(dep.key in self.tasks for dep in dependencies)
dependencies_fetch = set()
dependencies_missing = set()
for dependency_ts in dependencies:
if dependency_ts.state == "fetch":
if not dependency_ts.who_has:
dependencies_missing.add(dependency_ts)
else:
dependencies_fetch.add(dependency_ts)
del dependencies, dependency_ts
if dependencies_missing:
missing_deps2 = {
dep
for dep in dependencies_missing
if dep.key not in self._missing_dep_flight
}
for dep in missing_deps2:
self._missing_dep_flight.add(dep.key)
if missing_deps2:
logger.info(
"Can't find dependencies %s for key %s",
missing_deps2.copy(),
key,
)
self.loop.add_callback(self.handle_missing_dep, *missing_deps2)
dependencies_fetch -= dependencies_missing
self.log.append(
("gather-dependencies", key, {d.key for d in dependencies_fetch})
)
in_flight = False
while dependencies_fetch and (
len(self.in_flight_workers) < self.total_out_connections
or self.comm_nbytes < self.total_comm_nbytes
):
to_gather_ts = dependencies_fetch.pop()
workers = [
w
for w in to_gather_ts.who_has
if w not in self.in_flight_workers
]
if not workers:
in_flight = True
continue
host = get_address_host(self.address)
local = [w for w in workers if get_address_host(w) == host]
if local:
worker = random.choice(local)
else:
worker = random.choice(list(workers))
to_gather, total_nbytes = self.select_keys_for_gather(
worker, to_gather_ts.key
)
self.comm_nbytes += total_nbytes
self.in_flight_workers[worker] = to_gather
for d in to_gather:
dependencies_fetch.discard(self.tasks.get(d))
self.transition(self.tasks[d], "flight", worker=worker)
assert not worker == self.address
self.loop.add_callback(
self.gather_dep,
worker=worker,
to_gather=to_gather,
total_nbytes=total_nbytes,
cause=ts,
)
changed = True
if not dependencies_fetch and not in_flight:
self.data_needed.popleft()
except Exception as e:
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
def send_task_state_to_scheduler(self, ts):
if ts.key in self.data or self.actors.get(ts.key):
typ = ts.type
if ts.nbytes is None or typ is None:
try:
value = self.data[ts.key]
except KeyError:
value = self.actors[ts.key]
ts.nbytes = sizeof(value)
typ = ts.type = type(value)
del value
try:
typ_serialized = dumps_function(typ)
except PicklingError:
# Some types fail pickling (example: _thread.lock objects),
# send their name as a best effort.
typ_serialized = pickle.dumps(typ.__name__, protocol=4)
d = {
"op": "task-finished",
"status": "OK",
"key": ts.key,
"nbytes": ts.nbytes,
"thread": self.threads.get(ts.key),
"type": typ_serialized,
"typename": typename(typ),
"metadata": ts.metadata,
}
elif ts.exception is not None:
d = {
"op": "task-erred",
"status": "error",
"key": ts.key,
"thread": self.threads.get(ts.key),
"exception": ts.exception,
"traceback": ts.traceback,
}
else:
logger.error("Key not ready to send to worker, %s: %s", ts.key, ts.state)
return
if ts.startstops:
d["startstops"] = ts.startstops
self.batched_stream.send(d)
def put_key_in_memory(self, ts, value, transition=True):
if ts.key in self.data:
ts.state = "memory"
return
if ts.key in self.actors:
self.actors[ts.key] = value
else:
start = time()
self.data[ts.key] = value
ts.state = "memory"
stop = time()
if stop - start > 0.020:
ts.startstops.append(
{"action": "disk-write", "start": start, "stop": stop}
)
if ts.nbytes is None:
ts.nbytes = sizeof(value)
ts.type = type(value)
for dep in ts.dependents:
try:
dep.waiting_for_data.remove(ts.key)
self.waiting_for_data_count -= 1
except KeyError:
pass
if not dep.waiting_for_data:
self.transition(dep, "ready")
self.log.append((ts.key, "put-in-memory"))
def select_keys_for_gather(self, worker, dep):
assert isinstance(dep, str)
deps = {dep}
total_bytes = self.tasks[dep].get_nbytes()
L = self.pending_data_per_worker[worker]
while L:
d = L.popleft()
ts = self.tasks.get(d)
if ts is None or ts.state != "fetch":
continue
if total_bytes + ts.get_nbytes() > self.target_message_size:
break
deps.add(d)
total_bytes += ts.get_nbytes()
return deps, total_bytes
[docs] async def gather_dep(
self,
worker: str,
to_gather: Iterable[str],
total_nbytes: int,
cause: TaskState,
):
"""Gather dependencies for a task from a worker who has them
Parameters
----------
worker : str
Address of worker to gather dependencies from
to_gather : list
Keys of dependencies to gather from worker -- this is not
necessarily equivalent to the full list of dependencies of ``dep``
as some dependencies may already be present on this worker.
total_nbytes : int
Total number of bytes for all the dependencies in to_gather combined
cause : TaskState
Task we want to gather dependencies for
"""
if self.validate:
self.validate_state()
if self.status != Status.running:
return
with log_errors():
response = {}
to_gather_keys = set()
try:
if self.validate:
self.validate_state()
for dependency_key in to_gather:
dependency_ts = self.tasks.get(dependency_key)
if dependency_ts and dependency_ts.state == "flight":
to_gather_keys.add(dependency_key)
# Keep namespace clean since this func is long and has many
# dep*, *ts* variables
del to_gather, dependency_key, dependency_ts
self.log.append(("request-dep", cause.key, worker, to_gather_keys))
logger.debug(
"Request %d keys for task %s from %s",
len(to_gather_keys),
cause,
worker,
)
start = time()
response = await get_data_from_worker(
self.rpc, to_gather_keys, worker, who=self.address
)
stop = time()
if response["status"] == "busy":
self.log.append(("busy-gather", worker, to_gather_keys))
for key in to_gather_keys:
ts = self.tasks.get(key)
if ts and ts.state == "flight":
self.transition(ts, "fetch")
return
cause.startstops.append(
{
"action": "transfer",
"start": start + self.scheduler_delay,
"stop": stop + self.scheduler_delay,
"source": worker,
}
)
total_bytes = sum(
self.tasks[key].get_nbytes()
for key in response["data"]
if key in self.tasks
)
duration = (stop - start) or 0.010
bandwidth = total_bytes / duration
self.incoming_transfer_log.append(
{
"start": start + self.scheduler_delay,
"stop": stop + self.scheduler_delay,
"middle": (start + stop) / 2.0 + self.scheduler_delay,
"duration": duration,
"keys": {
key: self.tasks[key].nbytes
for key in response["data"]
if key in self.tasks
},
"total": total_bytes,
"bandwidth": bandwidth,
"who": worker,
}
)
if total_bytes > 1000000:
self.bandwidth = self.bandwidth * 0.95 + bandwidth * 0.05
bw, cnt = self.bandwidth_workers[worker]
self.bandwidth_workers[worker] = (bw + bandwidth, cnt + 1)
types = set(map(type, response["data"].values()))
if len(types) == 1:
[typ] = types
bw, cnt = self.bandwidth_types[typ]
self.bandwidth_types[typ] = (bw + bandwidth, cnt + 1)
if self.digests is not None:
self.digests["transfer-bandwidth"].add(total_bytes / duration)
self.digests["transfer-duration"].add(duration)
self.counters["transfer-count"].add(len(response["data"]))
self.incoming_count += 1
self.log.append(("receive-dep", worker, list(response["data"])))
except EnvironmentError:
logger.exception("Worker stream died during communication: %s", worker)
has_what = self.has_what.pop(worker)
self.pending_data_per_worker.pop(worker)
self.log.append(("receive-dep-failed", worker, has_what))
for d in has_what:
ts = self.tasks[d]
ts.who_has.remove(worker)
except Exception as e:
logger.exception(e)
if self.batched_stream and LOG_PDB:
import pdb
pdb.set_trace()
raise
finally:
self.comm_nbytes -= total_nbytes
busy = response.get("status", "") == "busy"
data = response.get("data", {})
# FIXME: We should not handle keys which were skipped by this coro. to_gather_keys is only a subset
assert set(to_gather_keys).issubset(
set(self.in_flight_workers.get(worker))
)
for d in self.in_flight_workers.pop(worker):
ts = self.tasks.get(d)
if not busy and d in data:
self.transition(ts, "memory", value=data[d])
elif ts is None or ts.state == "executing":
self.log.append(("already-executing", d))
self.release_key(d, reason="already executing at gather")
elif ts.state == "flight" and not ts.dependents:
self.log.append(("flight no-dependents", d))
self.release_key(
d, reason="In-flight task no longer has dependents."
)
elif (
not busy
and d not in data
and ts.dependents
and ts.state != "memory"
):
ts.who_has.discard(worker)
self.has_what[worker].discard(ts.key)
self.log.append(("missing-dep", d))
self.batched_stream.send(
{"op": "missing-data", "errant_worker": worker, "key": d}
)
self.transition(ts, "fetch")
elif ts.state not in ("ready", "memory"):
self.transition(ts, "fetch")
else:
logger.debug(
"Unexpected task state encountered for %s after gather_dep"
)
if self.validate:
self.validate_state()
await self.ensure_computing()
if not busy:
self.repetitively_busy = 0
self.ensure_communicating()
else:
# Exponential backoff to avoid hammering scheduler/worker
self.repetitively_busy += 1
await asyncio.sleep(0.100 * 1.5 ** self.repetitively_busy)
await self.query_who_has(*to_gather_keys)
self.ensure_communicating()
def bad_dep(self, dep):
exc = ValueError(
"Could not find dependent %s. Check worker logs" % str(dep.key)
)
for ts in dep.dependents:
msg = error_message(exc)
ts.exception = msg["exception"]
ts.traceback = msg["traceback"]
self.transition(ts, "error")
self.release_key(dep.key, reason="bad dep")
async def handle_missing_dep(self, *deps, **kwargs):
self.log.append(("handle-missing", deps))
try:
deps = {dep for dep in deps if dep.dependents}
if not deps:
return
for dep in deps:
if dep.suspicious_count > 5:
deps.remove(dep)
self.bad_dep(dep)
if not deps:
return
for dep in deps:
logger.info(
"Dependent not found: %s %s . Asking scheduler",
dep.key,
dep.suspicious_count,
)
who_has = await retry_operation(
self.scheduler.who_has, keys=list(dep.key for dep in deps)
)
who_has = {k: v for k, v in who_has.items() if v}
self.update_who_has(who_has)
still_missing = set()
for dep in deps:
dep.suspicious_count += 1
if not who_has.get(dep.key):
logger.info(
"No workers found for %s",
dep.key,
)
self.log.append((dep.key, "no workers found", dep.dependents))
self.release_key(dep.key, reason="Handle missing no workers")
elif self.address in who_has and dep.state != "memory":
still_missing.add(dep)
self.batched_stream.send(
{
"op": "release-worker-data",
"keys": [dep.key],
"worker": self.address,
}
)
else:
logger.debug("New workers found for %s", dep.key)
self.log.append((dep.key, "new workers found"))
for dependent in dep.dependents:
if dep.key in dependent.waiting_for_data:
self.data_needed.append(dependent.key)
if still_missing:
logger.debug(
"Found self referencing who has response from scheduler for keys %s.\n"
"Trying again handle_missing",
deps,
)
await self.handle_missing_dep(*deps)
except Exception:
logger.error("Handle missing dep failed, retrying", exc_info=True)
retries = kwargs.get("retries", 5)
self.log.append(("handle-missing-failed", retries, deps))
if retries > 0:
await self.handle_missing_dep(*deps, retries=retries - 1)
else:
raise
finally:
try:
for dep in deps:
self._missing_dep_flight.remove(dep.key)
except KeyError:
pass
self.ensure_communicating()
async def query_who_has(self, *deps):
with log_errors():
response = await retry_operation(self.scheduler.who_has, keys=deps)
self.update_who_has(response)
return response
def update_who_has(self, who_has):
try:
for dep, workers in who_has.items():
if not workers:
continue
if dep in self.tasks:
if self.address in workers and self.tasks[dep].state != "memory":
logger.debug(
"Scheduler claims worker %s holds data for task %s which is not true.",
self.name,
dep,
)
# Do not mutate the input dict. That's rude
workers = set(workers) - {self.address}
self.tasks[dep].who_has.update(workers)
for worker in workers:
self.has_what[worker].add(dep)
except Exception as e:
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
def steal_request(self, key):
# There may be a race condition between stealing and releasing a task.
# In this case the self.tasks is already cleared. The `None` will be
# registered as `already-computing` on the other end
ts = self.tasks.get(key)
if key in self.tasks:
state = ts.state
else:
state = None
response = {"op": "steal-response", "key": key, "state": state}
self.batched_stream.send(response)
if state in ("ready", "waiting", "constrained"):
# If task is marked as "constrained" we haven't yet assigned it an
# `available_resources` to run on, that happens in
# `transition_constrained_executing`
ts.scheduler_holds_ref = False
self.release_key(ts.key, reason="stolen")
if self.validate:
assert ts.key not in self.tasks
def release_key(
self,
key: str,
cause: Optional[TaskState] = None,
reason: Optional[str] = None,
report: bool = True,
):
try:
if self.validate:
assert isinstance(key, str)
ts = self.tasks.get(key, TaskState(key=key))
# If the scheduler holds a reference which is usually the
# case when it instructed the task to be computed here or if
# data was scattered we must not release it unless the
# scheduler allow us to. See also handle_delete_data and
if ts and ts.scheduler_holds_ref:
return
logger.debug(
"Release key %s",
{
"key": key,
"cause": cause,
"reason": reason,
},
)
if cause:
self.log.append((key, "release-key", {"cause": cause}, reason))
else:
self.log.append((key, "release-key", reason))
if key in self.data and not ts.dependents:
try:
del self.data[key]
except FileNotFoundError:
logger.error("Tried to delete %s but no file found", exc_info=True)
if key in self.actors and not ts.dependents:
del self.actors[key]
# for any dependencies of key we are releasing remove task as dependent
for dependency in ts.dependencies:
dependency.dependents.discard(ts)
if not dependency.dependents and dependency.state not in (
# don't boot keys that are in flight
# we don't know if they're already queued up for transit
# in a gather_dep callback
"flight",
# The same is true for already executing keys.
"executing",
):
self.release_key(dependency.key, reason=f"Dependent {ts} released")
for worker in ts.who_has:
self.has_what[worker].discard(ts.key)
ts.who_has.clear()
if key in self.threads:
del self.threads[key]
if ts.state == "executing":
self.executing_count -= 1
if ts.resource_restrictions is not None:
if ts.state == "executing":
for resource, quantity in ts.resource_restrictions.items():
self.available_resources[resource] += quantity
if report:
# Inform the scheduler of keys which will have gone missing
# We are releasing them before they have completed
if ts.state in PROCESSING:
msg = {"op": "release", "key": key, "cause": cause}
else:
msg = {
"op": "release-worker-data",
"keys": [key],
"worker": self.address,
}
self.batched_stream.send(msg)
self._notify_plugins("release_key", key, ts.state, cause, reason, report)
if key in self.tasks and not ts.dependents:
self.tasks.pop(key)
del ts
except CommClosedError:
pass
except Exception as e:
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
def rescind_key(self, key):
try:
if self.tasks[key].state not in PENDING:
return
ts = self.tasks.pop(key)
# Task has been rescinded
# For every task that it required
for dependency in ts.dependencies:
# Remove it as a dependent
dependency.dependents.remove(key)
# If the dependent is now without purpose (no dependencies), remove it
if not dependency.dependents:
self.release_key(
dependency.key, reason="All dependent keys rescinded"
)
except Exception as e:
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
################
# Execute Task #
################
# FIXME: this breaks if changed to async def...
# xref: https://github.com/dask/distributed/issues/3938
[docs] @gen.coroutine
def executor_submit(self, key, function, args=(), kwargs=None, executor=None):
"""Safely run function in thread pool executor
We've run into issues running concurrent.future futures within
tornado. Apparently it's advantageous to use timeouts and periodic
callbacks to ensure things run smoothly. This can get tricky, so we
pull it off into an separate method.
"""
executor = executor or self.executors["default"]
job_counter[0] += 1
# logger.info("%s:%d Starts job %d, %s", self.ip, self.port, i, key)
kwargs = kwargs or {}
future = executor.submit(function, *args, **kwargs)
pc = PeriodicCallback(
lambda: logger.debug("future state: %s - %s", key, future._state), 1000
)
ts = self.tasks.get(key)
if ts is not None:
ts.start_time = time()
pc.start()
try:
yield future
finally:
pc.stop()
if ts is not None:
ts.stop_time = time()
result = future.result()
# logger.info("Finish job %d, %s", i, key)
raise gen.Return(result)
def run(self, comm, function, args=(), wait=True, kwargs=None):
return run(self, comm, function=function, args=args, kwargs=kwargs, wait=wait)
def run_coroutine(self, comm, function, args=(), kwargs=None, wait=True):
return run(self, comm, function=function, args=args, kwargs=kwargs, wait=wait)
async def plugin_add(self, comm=None, plugin=None, name=None):
with log_errors(pdb=False):
if isinstance(plugin, bytes):
plugin = pickle.loads(plugin)
if name is None:
name = _get_worker_plugin_name(plugin)
assert name
if name in self.plugins:
return {"status": "repeat"}
else:
self.plugins[name] = plugin
logger.info("Starting Worker plugin %s" % name)
if hasattr(plugin, "setup"):
try:
result = plugin.setup(worker=self)
if isawaitable(result):
result = await result
except Exception as e:
msg = error_message(e)
return msg
return {"status": "OK"}
async def plugin_remove(self, comm=None, name=None):
with log_errors(pdb=False):
logger.info(f"Removing Worker plugin {name}")
try:
plugin = self.plugins.pop(name)
if hasattr(plugin, "teardown"):
result = plugin.teardown(worker=self)
if isawaitable(result):
result = await result
except Exception as e:
msg = error_message(e)
return msg
return {"status": "OK"}
async def actor_execute(
self, comm=None, actor=None, function=None, args=(), kwargs={}
):
separate_thread = kwargs.pop("separate_thread", True)
key = actor
actor = self.actors[key]
func = getattr(actor, function)
name = key_split(key) + "." + function
try:
if iscoroutinefunction(func):
result = await func(*args, **kwargs)
elif separate_thread:
result = await self.executor_submit(
name,
apply_function_actor,
args=(
func,
args,
kwargs,
self.execution_state,
name,
self.active_threads,
self.active_threads_lock,
),
executor=self.executors["actor"],
)
else:
result = func(*args, **kwargs)
return {"status": "OK", "result": to_serialize(result)}
except Exception as ex:
return {"status": "error", "exception": to_serialize(ex)}
def actor_attribute(self, comm=None, actor=None, attribute=None):
try:
value = getattr(self.actors[actor], attribute)
return {"status": "OK", "result": to_serialize(value)}
except Exception as ex:
return {"status": "error", "exception": to_serialize(ex)}
def meets_resource_constraints(self, key):
ts = self.tasks[key]
if not ts.resource_restrictions:
return True
for resource, needed in ts.resource_restrictions.items():
if self.available_resources[resource] < needed:
return False
return True
async def _maybe_deserialize_task(self, ts):
if not isinstance(ts.runspec, SerializedTask):
return ts.runspec
try:
start = time()
# Offload deserializing large tasks
if sizeof(ts.runspec) > OFFLOAD_THRESHOLD:
function, args, kwargs = await offload(_deserialize, *ts.runspec)
else:
function, args, kwargs = _deserialize(*ts.runspec)
stop = time()
if stop - start > 0.010:
ts.startstops.append(
{"action": "deserialize", "start": start, "stop": stop}
)
return function, args, kwargs
except Exception as e:
logger.warning("Could not deserialize task", exc_info=True)
emsg = error_message(e)
emsg["key"] = ts.key
emsg["op"] = "task-erred"
self.batched_stream.send(emsg)
self.log.append((ts.key, "deserialize-error"))
raise
async def ensure_computing(self):
if self.paused:
return
try:
while self.constrained and self.executing_count < self.nthreads:
key = self.constrained[0]
ts = self.tasks.get(key, None)
if ts is None or ts.state != "constrained":
self.constrained.popleft()
continue
if self.meets_resource_constraints(key):
self.constrained.popleft()
try:
# Ensure task is deserialized prior to execution
ts.runspec = await self._maybe_deserialize_task(ts)
except Exception:
continue
self.transition(ts, "executing")
else:
break
while self.ready and self.executing_count < self.nthreads:
priority, key = heapq.heappop(self.ready)
ts = self.tasks.get(key)
if ts is None:
# It is possible for tasks to be released while still remaining on `ready`
# The scheduler might have re-routed to a new worker and told this worker
# to release. If the task has "disappeared" just continue through the heap
continue
elif ts.key in self.data:
self.transition(ts, "memory")
elif ts.state in READY:
try:
# Ensure task is deserialized prior to execution
ts.runspec = await self._maybe_deserialize_task(ts)
except Exception:
continue
self.transition(ts, "executing")
except Exception as e:
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
async def execute(self, key, report=False):
executor_error = None
if self.status in (Status.closing, Status.closed, Status.closing_gracefully):
return
try:
if key not in self.tasks:
return
ts = self.tasks[key]
if ts.state != "executing":
# This might happen if keys are canceled
logger.debug(
"Trying to execute a task %s which is not in executing state anymore"
% ts
)
return
if ts.runspec is None:
logger.critical("No runspec available for task %s." % ts)
if self.validate:
assert not ts.waiting_for_data
assert ts.state == "executing"
function, args, kwargs = ts.runspec
start = time()
data = {}
for dep in ts.dependencies:
k = dep.key
try:
data[k] = self.data[k]
except KeyError:
from .actor import Actor # TODO: create local actor
data[k] = Actor(type(self.actors[k]), self.address, k, self)
args2 = pack_data(args, data, key_types=(bytes, str))
kwargs2 = pack_data(kwargs, data, key_types=(bytes, str))
stop = time()
if stop - start > 0.005:
ts.startstops.append(
{"action": "disk-read", "start": start, "stop": stop}
)
if self.digests is not None:
self.digests["disk-load-duration"].add(stop - start)
if ts.annotations is not None and "executor" in ts.annotations:
executor = ts.annotations["executor"]
else:
executor = "default"
assert executor in self.executors
logger.debug(
"Execute key: %s worker: %s, executor: %s",
ts.key,
self.address,
executor,
) # TODO: comment out?
assert key == ts.key
try:
result = await self.executor_submit(
ts.key,
apply_function,
args=(
function,
args2,
kwargs2,
self.execution_state,
ts.key,
self.active_threads,
self.active_threads_lock,
self.scheduler_delay,
),
executor=self.executors[executor],
)
except RuntimeError as e:
executor_error = e
raise
# We'll need to check again for the task state since it may have
# changed since the execution was kicked off. In particular, it may
# have been canceled and released already in which case we'll have
# to drop the result immediately
key = ts.key
ts = self.tasks.get(key)
if ts is None:
logger.debug(
"Dropping result for %s since task has already been released." % key
)
return
result["key"] = ts.key
value = result.pop("result", None)
ts.startstops.append(
{"action": "compute", "start": result["start"], "stop": result["stop"]}
)
self.threads[ts.key] = result["thread"]
if result["op"] == "task-finished":
ts.nbytes = result["nbytes"]
ts.type = result["type"]
self.transition(ts, "memory", value=value)
if self.digests is not None:
self.digests["task-duration"].add(result["stop"] - result["start"])
elif isinstance(result.pop("actual-exception"), Reschedule):
self.batched_stream.send({"op": "reschedule", "key": ts.key})
self.transition(ts, "rescheduled", report=False)
self.release_key(ts.key, report=False, reason="Reschedule")
else:
ts.exception = result["exception"]
ts.traceback = result["traceback"]
logger.warning(
"Compute Failed\n"
"Function: %s\n"
"args: %s\n"
"kwargs: %s\n"
"Exception: %r\n",
str(funcname(function))[:1000],
convert_args_to_str(args2, max_len=1000),
convert_kwargs_to_str(kwargs2, max_len=1000),
result["exception"].data,
)
self.transition(ts, "error")
logger.debug("Send compute response to scheduler: %s, %s", ts.key, result)
if self.validate:
assert ts.state != "executing"
assert not ts.waiting_for_data
await self.ensure_computing()
self.ensure_communicating()
except Exception as e:
if executor_error is e:
logger.error("Thread Pool Executor error: %s", e)
else:
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
##################
# Administrative #
##################
[docs] async def memory_monitor(self):
"""Track this process's memory usage and act accordingly
If we rise above 70% memory use, start dumping data to disk.
If we rise above 80% memory use, stop execution of new tasks
"""
if self._memory_monitoring:
return
self._memory_monitoring = True
total = 0
proc = self.monitor.proc
memory = proc.memory_info().rss
frac = memory / self.memory_limit
async def check_pause(memory):
frac = memory / self.memory_limit
# Pause worker threads if above 80% memory use
if self.memory_pause_fraction and frac > self.memory_pause_fraction:
# Try to free some memory while in paused state
self._throttled_gc.collect()
if not self.paused:
logger.warning(
"Worker is at %d%% memory usage. Pausing worker. "
"Process memory: %s -- Worker memory limit: %s",
int(frac * 100),
format_bytes(memory),
format_bytes(self.memory_limit)
if self.memory_limit is not None
else "None",
)
self.paused = True
elif self.paused:
logger.warning(
"Worker is at %d%% memory usage. Resuming worker. "
"Process memory: %s -- Worker memory limit: %s",
int(frac * 100),
format_bytes(memory),
format_bytes(self.memory_limit)
if self.memory_limit is not None
else "None",
)
self.paused = False
await self.ensure_computing()
await check_pause(memory)
# Dump data to disk if above 70%
if self.memory_spill_fraction and frac > self.memory_spill_fraction:
logger.debug(
"Worker is at %.0f%% memory usage. Start spilling data to disk.",
frac * 100,
)
start = time()
target = self.memory_limit * self.memory_target_fraction
count = 0
need = memory - target
while memory > target:
if not self.data.fast:
logger.warning(
"Unmanaged memory use is high. This may indicate a memory leak "
"or the memory may not be released to the OS; see "
"https://distributed.dask.org/en/latest/worker.html#memtrim "
"for more information. "
"-- Unmanaged memory: %s -- Worker memory limit: %s",
format_bytes(memory),
format_bytes(self.memory_limit),
)
break
k, v, weight = self.data.fast.evict()
del k, v
total += weight
count += 1
# If the current buffer is filled with a lot of small values,
# evicting one at a time is very slow and the worker might
# generate new data faster than it is able to evict. Therefore,
# only pass on control if we spent at least 0.5s evicting
if time() - start > 0.5:
await asyncio.sleep(0)
start = time()
memory = proc.memory_info().rss
if total > need and memory > target:
# Issue a GC to ensure that the evicted data is actually
# freed from memory and taken into account by the monitor
# before trying to evict even more data.
self._throttled_gc.collect()
memory = proc.memory_info().rss
await check_pause(memory)
if count:
logger.debug(
"Moved %d pieces of data data and %s to disk",
count,
format_bytes(total),
)
self._memory_monitoring = False
return total
def cycle_profile(self):
now = time() + self.scheduler_delay
prof, self.profile_recent = self.profile_recent, profile.create()
self.profile_history.append((now, prof))
self.profile_keys_history.append((now, dict(self.profile_keys)))
self.profile_keys.clear()
[docs] def trigger_profile(self):
"""
Get a frame from all actively computing threads
Merge these frames into existing profile counts
"""
if not self.active_threads: # hope that this is thread-atomic?
return
start = time()
with self.active_threads_lock:
active_threads = self.active_threads.copy()
frames = sys._current_frames()
frames = {ident: frames[ident] for ident in active_threads}
llframes = {}
if self.low_level_profiler:
llframes = {ident: profile.ll_get_stack(ident) for ident in active_threads}
for ident, frame in frames.items():
if frame is not None:
key = key_split(active_threads[ident])
llframe = llframes.get(ident)
state = profile.process(
frame, True, self.profile_recent, stop="distributed/worker.py"
)
profile.llprocess(llframe, None, state)
profile.process(
frame, True, self.profile_keys[key], stop="distributed/worker.py"
)
stop = time()
if self.digests is not None:
self.digests["profile-duration"].add(stop - start)
async def get_profile(
self, comm=None, start=None, stop=None, key=None, server=False
):
now = time() + self.scheduler_delay
if server:
history = self.io_loop.profile
elif key is None:
history = self.profile_history
else:
history = [(t, d[key]) for t, d in self.profile_keys_history if key in d]
if start is None:
istart = 0
else:
istart = bisect.bisect_left(history, (start,))
if stop is None:
istop = None
else:
istop = bisect.bisect_right(history, (stop,)) + 1
if istop >= len(history):
istop = None # include end
if istart == 0 and istop is None:
history = list(history)
else:
iistop = len(history) if istop is None else istop
history = [history[i] for i in range(istart, iistop)]
prof = profile.merge(*pluck(1, history))
if not history:
return profile.create()
if istop is None and (start is None or start < now):
if key is None:
recent = self.profile_recent
else:
recent = self.profile_keys[key]
prof = profile.merge(prof, recent)
return prof
async def get_profile_metadata(self, comm=None, start=0, stop=None):
if stop is None:
add_recent = True
now = time() + self.scheduler_delay
stop = stop or now
start = start or 0
result = {
"counts": [
(t, d["count"]) for t, d in self.profile_history if start < t < stop
],
"keys": [
(t, {k: d["count"] for k, d in v.items()})
for t, v in self.profile_keys_history
if start < t < stop
],
}
if add_recent:
result["counts"].append((now, self.profile_recent["count"]))
result["keys"].append(
(now, {k: v["count"] for k, v in self.profile_keys.items()})
)
return result
def get_call_stack(self, comm=None, keys=None):
with self.active_threads_lock:
frames = sys._current_frames()
active_threads = self.active_threads.copy()
frames = {k: frames[ident] for ident, k in active_threads.items()}
if keys is not None:
frames = {k: frame for k, frame in frames.items() if k in keys}
result = {k: profile.call_stack(frame) for k, frame in frames.items()}
return result
def _notify_plugins(self, method_name, *args, **kwargs):
for name, plugin in self.plugins.items():
if hasattr(plugin, method_name):
try:
getattr(plugin, method_name)(*args, **kwargs)
except Exception:
logger.info(
"Plugin '%s' failed with exception" % name, exc_info=True
)
##############
# Validation #
##############
def validate_task_memory(self, ts):
assert ts.key in self.data or ts.key in self.actors
assert isinstance(ts.nbytes, int)
assert not ts.waiting_for_data
assert ts.key not in self.ready
assert ts.state == "memory"
def validate_task_executing(self, ts):
assert ts.state == "executing"
assert ts.runspec is not None
assert ts.key not in self.data
assert not ts.waiting_for_data
assert all(
dep.key in self.data or dep.key in self.actors for dep in ts.dependencies
)
def validate_task_ready(self, ts):
assert ts.key in pluck(1, self.ready)
assert ts.key not in self.data
assert ts.state != "executing"
assert not ts.waiting_for_data
assert all(
dep.key in self.data or dep.key in self.actors for dep in ts.dependencies
)
def validate_task_waiting(self, ts):
assert ts.key not in self.data
assert ts.state == "waiting"
if ts.dependencies and ts.runspec:
assert not all(dep.key in self.data for dep in ts.dependencies)
def validate_task_flight(self, ts):
assert ts.key not in self.data
assert not any(dep.key in self.ready for dep in ts.dependents)
assert ts.coming_from
assert ts.coming_from in self.in_flight_workers
assert ts.key in self.in_flight_workers[ts.coming_from]
def validate_task_fetch(self, ts):
assert ts.runspec is None
assert ts.key not in self.data
assert self.address not in ts.who_has #!!!!!!!!
# FIXME This is currently not an invariant since upon comm failure we
# remove the erroneous worker from all who_has and correct the state
# upon the next ensure_communicate
# if not ts.who_has:
# # If we do not know who_has for a fetch task, it must be logged in
# # the missing dep. There should be a handle_missing_dep running for
# # all of these keys
# assert ts.key in self._missing_dep_flight, (
# ts.key,
# self.story(ts),
# self._missing_dep_flight.copy(),
# self.in_flight_workers.copy(),
# )
assert ts.dependents
for w in ts.who_has:
assert ts.key in self.has_what[w]
def validate_task(self, ts):
try:
if ts.state == "memory":
self.validate_task_memory(ts)
elif ts.state == "waiting":
self.validate_task_waiting(ts)
elif ts.state == "ready":
self.validate_task_ready(ts)
elif ts.state == "executing":
self.validate_task_executing(ts)
elif ts.state == "flight":
self.validate_task_flight(ts)
elif ts.state == "fetch":
self.validate_task_fetch(ts)
except Exception as e:
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
def validate_state(self):
if self.status != Status.running:
return
try:
for ts in self.tasks.values():
assert ts.state is not None
# check that worker has task
for worker in ts.who_has:
assert ts.key in self.has_what[worker]
# check that deps have a set state and that dependency<->dependent links are there
for dep in ts.dependencies:
# self.tasks was just a dict of tasks
# and this check was originally that the key was in `task_state`
# so we may have popped the key out of `self.tasks` but the
# dependency can still be in `memory` before GC grabs it...?
# Might need better bookkeeping
assert dep.state is not None
assert ts in dep.dependents, ts
for key in ts.waiting_for_data:
ts_wait = self.tasks[key]
assert (
ts_wait.state == "flight"
or ts_wait.state == "fetch"
or ts_wait.key in self._missing_dep_flight
or ts_wait.who_has.issubset(self.in_flight_workers)
)
if ts.state == "memory":
assert isinstance(ts.nbytes, int)
assert not ts.waiting_for_data
assert ts.key in self.data or ts.key in self.actors
for worker, keys in self.has_what.items():
for k in keys:
assert worker in self.tasks[k].who_has
for ts in self.tasks.values():
self.validate_task(ts)
except Exception as e:
self.loop.add_callback(self.close)
logger.exception(e)
if LOG_PDB:
import pdb
pdb.set_trace()
raise
#######################################
# Worker Clients (advanced workloads) #
#######################################
@property
def client(self):
with self._lock:
if self._client:
return self._client
else:
return self._get_client()
def _get_client(self, timeout=None):
"""Get local client attached to this worker
If no such client exists, create one
See Also
--------
get_client
"""
if timeout is None:
timeout = dask.config.get("distributed.comm.timeouts.connect")
timeout = parse_timedelta(timeout, "s")
try:
from .client import default_client
client = default_client()
except ValueError: # no clients found, need to make a new one
pass
else:
# must be lazy import otherwise cyclic import
from distributed.deploy.cluster import Cluster
if (
client.scheduler
and client.scheduler.address == self.scheduler.address
# The below conditions should only happen in case a second
# cluster is alive, e.g. if a submitted task spawned its onwn
# LocalCluster, see gh4565
or (
isinstance(client._start_arg, str)
and client._start_arg == self.scheduler.address
or isinstance(client._start_arg, Cluster)
and client._start_arg.scheduler_address == self.scheduler.address
)
):
self._client = client
if not self._client:
from .client import Client
asynchronous = self.loop is IOLoop.current()
self._client = Client(
self.scheduler,
loop=self.loop,
security=self.security,
set_as_default=True,
asynchronous=asynchronous,
direct_to_workers=True,
name="worker",
timeout=timeout,
)
Worker._initialized_clients.add(self._client)
if not asynchronous:
assert self._client.status == "running"
return self._client
[docs] def get_current_task(self):
"""Get the key of the task we are currently running
This only makes sense to run within a task
Examples
--------
>>> from dask.distributed import get_worker
>>> def f():
... return get_worker().get_current_task()
>>> future = client.submit(f) # doctest: +SKIP
>>> future.result() # doctest: +SKIP
'f-1234'
See Also
--------
get_worker
"""
return self.active_threads[threading.get_ident()]
def get_worker():
"""Get the worker currently running this task
Examples
--------
>>> def f():
... worker = get_worker() # The worker on which this task is running
... return worker.address
>>> future = client.submit(f) # doctest: +SKIP
>>> future.result() # doctest: +SKIP
'tcp://127.0.0.1:47373'
See Also
--------
get_client
worker_client
"""
try:
return thread_state.execution_state["worker"]
except AttributeError:
try:
return first(w for w in Worker._instances if w.status == Status.running)
except StopIteration:
raise ValueError("No workers found")
[docs]def get_client(address=None, timeout=None, resolve_address=True):
"""Get a client while within a task.
This client connects to the same scheduler to which the worker is connected
Parameters
----------
address : str, optional
The address of the scheduler to connect to. Defaults to the scheduler
the worker is connected to.
timeout : int or str
Timeout (in seconds) for getting the Client. Defaults to the
``distributed.comm.timeouts.connect`` configuration value.
resolve_address : bool, default True
Whether to resolve `address` to its canonical form.
Returns
-------
Client
Examples
--------
>>> def f():
... client = get_client(timeout="10s")
... futures = client.map(lambda x: x + 1, range(10)) # spawn many tasks
... results = client.gather(futures)
... return sum(results)
>>> future = client.submit(f) # doctest: +SKIP
>>> future.result() # doctest: +SKIP
55
See Also
--------
get_worker
worker_client
secede
"""
if timeout is None:
timeout = dask.config.get("distributed.comm.timeouts.connect")
timeout = parse_timedelta(timeout, "s")
if address and resolve_address:
address = comm.resolve_address(address)
try:
worker = get_worker()
except ValueError: # could not find worker
pass
else:
if not address or worker.scheduler.address == address:
return worker._get_client(timeout=timeout)
from .client import Client
try:
client = Client.current() # TODO: assumes the same scheduler
except ValueError:
client = None
if client and (not address or client.scheduler.address == address):
return client
elif address:
return Client(address, timeout=timeout)
else:
raise ValueError("No global client found and no address provided")
[docs]def secede():
"""
Have this task secede from the worker's thread pool
This opens up a new scheduling slot and a new thread for a new task. This
enables the client to schedule tasks on this node, which is
especially useful while waiting for other jobs to finish (e.g., with
``client.gather``).
Examples
--------
>>> def mytask(x):
... # do some work
... client = get_client()
... futures = client.map(...) # do some remote work
... secede() # while that work happens, remove ourself from the pool
... return client.gather(futures) # return gathered results
See Also
--------
get_client
get_worker
"""
worker = get_worker()
tpe_secede() # have this thread secede from the thread pool
duration = time() - thread_state.start_time
worker.loop.add_callback(
worker.maybe_transition_long_running,
worker.tasks[thread_state.key],
compute_duration=duration,
)
class Reschedule(Exception):
"""Reschedule this task
Raising this exception will stop the current execution of the task and ask
the scheduler to reschedule this task, possibly on a different machine.
This does not guarantee that the task will move onto a different machine.
The scheduler will proceed through its normal heuristics to determine the
optimal machine to accept this task. The machine will likely change if the
load across the cluster has significantly changed since first scheduling
the task.
"""
def parse_memory_limit(memory_limit, nthreads, total_cores=CPU_COUNT):
if memory_limit is None:
return None
if memory_limit == "auto":
memory_limit = int(system.MEMORY_LIMIT * min(1, nthreads / total_cores))
with suppress(ValueError, TypeError):
memory_limit = float(memory_limit)
if isinstance(memory_limit, float) and memory_limit <= 1:
memory_limit = int(memory_limit * system.MEMORY_LIMIT)
if isinstance(memory_limit, str):
memory_limit = parse_bytes(memory_limit)
else:
memory_limit = int(memory_limit)
return min(memory_limit, system.MEMORY_LIMIT)
async def get_data_from_worker(
rpc,
keys,
worker,
who=None,
max_connections=None,
serializers=None,
deserializers=None,
):
"""Get keys from worker
The worker has a two step handshake to acknowledge when data has been fully
delivered. This function implements that handshake.
See Also
--------
Worker.get_data
Worker.gather_deps
utils_comm.gather_data_from_workers
"""
if serializers is None:
serializers = rpc.serializers
if deserializers is None:
deserializers = rpc.deserializers
async def _get_data():
comm = await rpc.connect(worker)
comm.name = "Ephemeral Worker->Worker for gather"
try:
response = await send_recv(
comm,
serializers=serializers,
deserializers=deserializers,
op="get_data",
keys=keys,
who=who,
max_connections=max_connections,
)
try:
status = response["status"]
except KeyError:
raise ValueError("Unexpected response", response)
else:
if status == "OK":
await comm.write("OK")
return response
finally:
rpc.reuse(worker, comm)
return await retry_operation(_get_data, operation="get_data_from_worker")
job_counter = [0]
cache_loads = LRU(maxsize=100)
def loads_function(bytes_object):
"""Load a function from bytes, cache bytes"""
if len(bytes_object) < 100000:
try:
result = cache_loads[bytes_object]
except KeyError:
result = pickle.loads(bytes_object)
cache_loads[bytes_object] = result
return result
return pickle.loads(bytes_object)
def _deserialize(function=None, args=None, kwargs=None, task=no_value):
"""Deserialize task inputs and regularize to func, args, kwargs"""
if function is not None:
function = loads_function(function)
if args and isinstance(args, bytes):
args = pickle.loads(args)
if kwargs and isinstance(kwargs, bytes):
kwargs = pickle.loads(kwargs)
if task is not no_value:
assert not function and not args and not kwargs
function = execute_task
args = (task,)
return function, args or (), kwargs or {}
def execute_task(task):
"""Evaluate a nested task
>>> inc = lambda x: x + 1
>>> execute_task((inc, 1))
2
>>> execute_task((sum, [1, 2, (inc, 3)]))
7
"""
if istask(task):
func, args = task[0], task[1:]
return func(*map(execute_task, args))
elif isinstance(task, list):
return list(map(execute_task, task))
else:
return task
cache_dumps = LRU(maxsize=100)
_cache_lock = threading.Lock()
def dumps_function(func):
"""Dump a function to bytes, cache functions"""
try:
with _cache_lock:
result = cache_dumps[func]
except KeyError:
result = pickle.dumps(func, protocol=4)
if len(result) < 100000:
with _cache_lock:
cache_dumps[func] = result
except TypeError: # Unhashable function
result = pickle.dumps(func, protocol=4)
return result
def dumps_task(task):
"""Serialize a dask task
Returns a dict of bytestrings that can each be loaded with ``loads``
Examples
--------
Either returns a task as a function, args, kwargs dict
>>> from operator import add
>>> dumps_task((add, 1)) # doctest: +SKIP
{'function': b'\x80\x04\x95\x00\x8c\t_operator\x94\x8c\x03add\x94\x93\x94.'
'args': b'\x80\x04\x95\x07\x00\x00\x00K\x01K\x02\x86\x94.'}
Or as a single task blob if it can't easily decompose the result. This
happens either if the task is highly nested, or if it isn't a task at all
>>> dumps_task(1) # doctest: +SKIP
{'task': b'\x80\x04\x95\x03\x00\x00\x00\x00\x00\x00\x00K\x01.'}
"""
if istask(task):
if task[0] is apply and not any(map(_maybe_complex, task[2:])):
d = {"function": dumps_function(task[1]), "args": warn_dumps(task[2])}
if len(task) == 4:
d["kwargs"] = warn_dumps(task[3])
return d
elif not any(map(_maybe_complex, task[1:])):
return {"function": dumps_function(task[0]), "args": warn_dumps(task[1:])}
return to_serialize(task)
_warn_dumps_warned = [False]
def warn_dumps(obj, dumps=pickle.dumps, limit=1e6):
"""Dump an object to bytes, warn if those bytes are large"""
b = dumps(obj, protocol=4)
if not _warn_dumps_warned[0] and len(b) > limit:
_warn_dumps_warned[0] = True
s = str(obj)
if len(s) > 70:
s = s[:50] + " ... " + s[-15:]
warnings.warn(
"Large object of size %s detected in task graph: \n"
" %s\n"
"Consider scattering large objects ahead of time\n"
"with client.scatter to reduce scheduler burden and \n"
"keep data on workers\n\n"
" future = client.submit(func, big_data) # bad\n\n"
" big_future = client.scatter(big_data) # good\n"
" future = client.submit(func, big_future) # good"
% (format_bytes(len(b)), s)
)
return b
def apply_function(
function,
args,
kwargs,
execution_state,
key,
active_threads,
active_threads_lock,
time_delay,
):
"""Run a function, collect information
Returns
-------
msg: dictionary with status, result/error, timings, etc..
"""
ident = threading.get_ident()
with active_threads_lock:
active_threads[ident] = key
thread_state.start_time = time()
thread_state.execution_state = execution_state
thread_state.key = key
start = time()
try:
result = function(*args, **kwargs)
except Exception as e:
msg = error_message(e)
msg["op"] = "task-erred"
msg["actual-exception"] = e
else:
msg = {
"op": "task-finished",
"status": "OK",
"result": result,
"nbytes": sizeof(result),
"type": type(result) if result is not None else None,
}
finally:
end = time()
msg["start"] = start + time_delay
msg["stop"] = end + time_delay
msg["thread"] = ident
with active_threads_lock:
del active_threads[ident]
return msg
def apply_function_actor(
function, args, kwargs, execution_state, key, active_threads, active_threads_lock
):
"""Run a function, collect information
Returns
-------
msg: dictionary with status, result/error, timings, etc..
"""
ident = threading.get_ident()
with active_threads_lock:
active_threads[ident] = key
thread_state.execution_state = execution_state
thread_state.key = key
thread_state.actor = True
result = function(*args, **kwargs)
with active_threads_lock:
del active_threads[ident]
return result
def get_msg_safe_str(msg):
"""Make a worker msg, which contains args and kwargs, safe to cast to str:
allowing for some arguments to raise exceptions during conversion and
ignoring them.
"""
class Repr:
def __init__(self, f, val):
self._f = f
self._val = val
def __repr__(self):
return self._f(self._val)
msg = msg.copy()
if "args" in msg:
msg["args"] = Repr(convert_args_to_str, msg["args"])
if "kwargs" in msg:
msg["kwargs"] = Repr(convert_kwargs_to_str, msg["kwargs"])
return msg
def convert_args_to_str(args, max_len=None):
"""Convert args to a string, allowing for some arguments to raise
exceptions during conversion and ignoring them.
"""
length = 0
strs = ["" for i in range(len(args))]
for i, arg in enumerate(args):
try:
sarg = repr(arg)
except Exception:
sarg = "< could not convert arg to str >"
strs[i] = sarg
length += len(sarg) + 2
if max_len is not None and length > max_len:
return "({}".format(", ".join(strs[: i + 1]))[:max_len]
else:
return "({})".format(", ".join(strs))
def convert_kwargs_to_str(kwargs, max_len=None):
"""Convert kwargs to a string, allowing for some arguments to raise
exceptions during conversion and ignoring them.
"""
length = 0
strs = ["" for i in range(len(kwargs))]
for i, (argname, arg) in enumerate(kwargs.items()):
try:
sarg = repr(arg)
except Exception:
sarg = "< could not convert arg to str >"
skwarg = repr(argname) + ": " + sarg
strs[i] = skwarg
length += len(skwarg) + 2
if max_len is not None and length > max_len:
return "{{{}".format(", ".join(strs[: i + 1]))[:max_len]
else:
return "{{{}}}".format(", ".join(strs))
@deprecated(version_removed="2021.06.0")
def weight(k, v):
return sizeof(v)
async def run(server, comm, function, args=(), kwargs=None, is_coro=None, wait=True):
kwargs = kwargs or {}
function = pickle.loads(function)
if is_coro is None:
is_coro = iscoroutinefunction(function)
else:
warnings.warn(
"The is_coro= parameter is deprecated. "
"We now automatically detect coroutines/async functions"
)
assert wait or is_coro, "Combination not supported"
if args:
args = pickle.loads(args)
if kwargs:
kwargs = pickle.loads(kwargs)
if has_arg(function, "dask_worker"):
kwargs["dask_worker"] = server
if has_arg(function, "dask_scheduler"):
kwargs["dask_scheduler"] = server
logger.info("Run out-of-band function %r", funcname(function))
try:
if not is_coro:
result = function(*args, **kwargs)
else:
if wait:
result = await function(*args, **kwargs)
else:
server.loop.add_callback(function, *args, **kwargs)
result = None
except Exception as e:
logger.warning(
"Run Failed\nFunction: %s\nargs: %s\nkwargs: %s\n",
str(funcname(function))[:1000],
convert_args_to_str(args, max_len=1000),
convert_kwargs_to_str(kwargs, max_len=1000),
exc_info=True,
)
response = error_message(e)
else:
response = {"status": "OK", "result": to_serialize(result)}
return response
_global_workers = Worker._instances
try:
if nvml.device_get_count() < 1:
raise RuntimeError
except (Exception, RuntimeError):
pass
else:
@gen.coroutine
def gpu_metric(worker):
result = yield offload(nvml.real_time)
return result
DEFAULT_METRICS["gpu"] = gpu_metric
def gpu_startup(worker):
return nvml.one_time()
DEFAULT_STARTUP_INFORMATION["gpu"] = gpu_startup