def __init__(self,
env_fns,
observation_space=None,
action_space=None,
shared_memory=True,
copy=True,
context=None):
try:
ctx = mp.get_context(context)
except AttributeError:
logger.warn('Context switching for `multiprocessing` is not '
'available in Python 2. Using the default context.')
ctx = mp
self.env_fns = env_fns
self.shared_memory = shared_memory
self.copy = copy
if (observation_space is None) or (action_space is None):
dummy_env = env_fns[0]()
observation_space = observation_space or dummy_env.observation_space
action_space = action_space or dummy_env.action_space
dummy_env.close()
del dummy_env
super(AsyncVectorEnv,
self).__init__(num_envs=len(env_fns),
observation_space=observation_space,
action_space=action_space)
if self.shared_memory:
_obs_buffer = create_shared_memory(self.single_observation_space,
n=self.num_envs)
self.observations = read_from_shared_memory(
_obs_buffer, self.single_observation_space, n=self.num_envs)
else:
_obs_buffer = None
self.observations = create_empty_array(
self.single_observation_space, n=self.num_envs, fn=np.zeros)
self.parent_pipes, self.processes = [], []
self.error_queue = ctx.Queue()
target = _worker_shared_memory if self.shared_memory else _worker
with clear_mpi_env_vars():
for idx, env_fn in enumerate(self.env_fns):
parent_pipe, child_pipe = ctx.Pipe()
process = ctx.Process(
target=target,
name='Worker<{0}>-{1}'.format(type(self).__name__, idx),
args=(idx, CloudpickleWrapper(env_fn), child_pipe,
parent_pipe, _obs_buffer, self.error_queue))
self.parent_pipes.append(parent_pipe)
self.processes.append(process)
process.daemon = True
process.start()
child_pipe.close()
self._state = AsyncState.DEFAULT
self._check_observation_spaces()
def __init__(self, env_fns, observation_space=None, action_space=None,
shared_memory=True, copy=True, context=None, daemon=True, worker=None):
ctx = mp.get_context(context)
self.env_fns = env_fns
self.shared_memory = shared_memory
self.copy = copy
if (observation_space is None) or (action_space is None):
dummy_env = env_fns[0]()
observation_space = observation_space or dummy_env.observation_space
action_space = action_space or dummy_env.action_space
dummy_env.close()
del dummy_env
super(AsyncVectorEnv, self).__init__(num_envs=len(env_fns),
observation_space=observation_space, action_space=action_space)
if self.shared_memory:
try:
_obs_buffer = create_shared_memory(self.single_observation_space,
n=self.num_envs, ctx=ctx)
self.observations = read_from_shared_memory(_obs_buffer,
self.single_observation_space, n=self.num_envs)
except CustomSpaceError:
raise ValueError('Using `shared_memory=True` in `AsyncVectorEnv` '
'is incompatible with non-standard Gym observation spaces '
'(i.e. custom spaces inheriting from `gym.Space`), and is '
'only compatible with default Gym spaces (e.g. `Box`, '
'`Tuple`, `Dict`) for batching. Set `shared_memory=False` '
'if you use custom observation spaces.')
else:
_obs_buffer = None
self.observations = create_empty_array(
self.single_observation_space, n=self.num_envs, fn=np.zeros)
self.parent_pipes, self.processes = [], []
self.error_queue = ctx.Queue()
target = _worker_shared_memory if self.shared_memory else _worker
target = worker or target
with clear_mpi_env_vars():
for idx, env_fn in enumerate(self.env_fns):
parent_pipe, child_pipe = ctx.Pipe()
process = ctx.Process(target=target,
name='Worker<{0}>-{1}'.format(type(self).__name__, idx),
args=(idx, CloudpickleWrapper(env_fn), child_pipe,
parent_pipe, _obs_buffer, self.error_queue))
self.parent_pipes.append(parent_pipe)
self.processes.append(process)
process.daemon = daemon
process.start()
child_pipe.close()
self._state = AsyncState.DEFAULT
self._check_observation_spaces()
def __init__(
self,
env_fns: Sequence[callable],
observation_space: Optional[gym.Space] = None,
action_space: Optional[gym.Space] = None,
shared_memory: bool = True,
copy: bool = True,
context: Optional[str] = None,
daemon: bool = True,
worker: Optional[callable] = None,
):
"""Vectorized environment that runs multiple environments in parallel.
Args:
env_fns: Functions that create the environments.
observation_space: Observation space of a single environment. If ``None``, then the observation space of the first environment is taken.
action_space: Action space of a single environment. If ``None``, then the action space of the first environment is taken.
shared_memory: If ``True``, then the observations from the worker processes are communicated back through shared variables. This can improve the efficiency if the observations are large (e.g. images).
copy: If ``True``, then the :meth:`~AsyncVectorEnv.reset` and :meth:`~AsyncVectorEnv.step` methods return a copy of the observations.
context: Context for `multiprocessing`_. If ``None``, then the default context is used.
daemon: If ``True``, then subprocesses have ``daemon`` flag turned on; that is, they will quit if the head process quits. However, ``daemon=True`` prevents subprocesses to spawn children, so for some environments you may want to have it set to ``False``.
worker: If set, then use that worker in a subprocess instead of a default one. Can be useful to override some inner vector env logic, for instance, how resets on done are handled.
Warnings: worker is an advanced mode option. It provides a high degree of flexibility and a high chance to shoot yourself in the foot; thus, if you are writing your own worker, it is recommended to start from the code for ``_worker`` (or ``_worker_shared_memory``) method, and add changes.
Raises:
RuntimeError: If the observation space of some sub-environment does not match observation_space (or, by default, the observation space of the first sub-environment).
ValueError: If observation_space is a custom space (i.e. not a default space in Gym, such as gym.spaces.Box, gym.spaces.Discrete, or gym.spaces.Dict) and shared_memory is True.
"""
ctx = mp.get_context(context)
self.env_fns = env_fns
self.shared_memory = shared_memory
self.copy = copy
dummy_env = env_fns[0]()
self.metadata = dummy_env.metadata
if (observation_space is None) or (action_space is None):
observation_space = observation_space or dummy_env.observation_space
action_space = action_space or dummy_env.action_space
dummy_env.close()
del dummy_env
super().__init__(
num_envs=len(env_fns),
observation_space=observation_space,
action_space=action_space,
)
if self.shared_memory:
try:
_obs_buffer = create_shared_memory(
self.single_observation_space, n=self.num_envs, ctx=ctx)
self.observations = read_from_shared_memory(
self.single_observation_space,
_obs_buffer,
n=self.num_envs)
except CustomSpaceError:
raise ValueError(
"Using `shared_memory=True` in `AsyncVectorEnv` "
"is incompatible with non-standard Gym observation spaces "
"(i.e. custom spaces inheriting from `gym.Space`), and is "
"only compatible with default Gym spaces (e.g. `Box`, "
"`Tuple`, `Dict`) for batching. Set `shared_memory=False` "
"if you use custom observation spaces.")
else:
_obs_buffer = None
self.observations = create_empty_array(
self.single_observation_space, n=self.num_envs, fn=np.zeros)
self.parent_pipes, self.processes = [], []
self.error_queue = ctx.Queue()
target = _worker_shared_memory if self.shared_memory else _worker
target = worker or target
with clear_mpi_env_vars():
for idx, env_fn in enumerate(self.env_fns):
parent_pipe, child_pipe = ctx.Pipe()
process = ctx.Process(
target=target,
name=f"Worker<{type(self).__name__}>-{idx}",
args=(
idx,
CloudpickleWrapper(env_fn),
child_pipe,
parent_pipe,
_obs_buffer,
self.error_queue,
),
)
self.parent_pipes.append(parent_pipe)
self.processes.append(process)
process.daemon = daemon
process.start()
child_pipe.close()
self._state = AsyncState.DEFAULT
self._check_spaces()