def start_worker(self):
"""Start workers."""
n_envs = self.n_envs
envs = [pickle.loads(pickle.dumps(self.env)) for _ in range(n_envs)]
self.vec_env = VecEnvExecutor(
envs=envs, max_path_length=self.algo.max_path_length)
self.env_spec = self.env.spec
def _setup_worker(self, env_indices, tasks):
"""Setup workers.
Args:
env_indices (List[Int]): Indices of environments to be assigned
to workers for sampling.
tasks (List[dict]): List of tasks to assign.
"""
if self._vec_env is not None:
self._vec_env.close()
vec_envs = []
for env_ind in env_indices:
for _ in range(self._envs_per_worker):
vec_env = copy.deepcopy(self.env)
vec_env.set_task(tasks[env_ind])
vec_envs.append(vec_env)
seed0 = deterministic.get_seed()
if seed0 is not None:
for (i, e) in enumerate(vec_envs):
e.seed(seed0 + i)
self._vec_env = VecEnvExecutor(
envs=vec_envs, max_path_length=self.algo.max_path_length)
def start_worker(self):
"""Start workers."""
n_envs = self.n_envs
envs = [pickle.loads(pickle.dumps(self.env)) for _ in range(n_envs)]
# Deterministically set environment seeds based on the global seed.
for (i, e) in enumerate(envs):
e.seed(deterministic.get_seed() + i)
self.vec_env = VecEnvExecutor(
envs=envs, max_path_length=self.algo.max_path_length)
self.env_spec = self.env.spec
def start_worker(self):
"""Initialize the sampler."""
n_envs = self._n_envs
envs = [pickle.loads(pickle.dumps(self.env)) for _ in range(n_envs)]
# Deterministically set environment seeds based on the global seed.
seed0 = deterministic.get_seed()
if seed0 is not None:
for (i, e) in enumerate(envs):
e.seed(seed0 + i)
self._vec_env = VecEnvExecutor(
envs=envs, max_path_length=self.algo.max_path_length)
class OnPolicyVectorizedSampler(BatchSampler):
"""BatchSampler which uses VecEnvExecutor to run multiple environments."""
def __init__(self, algo, env, n_envs=None):
if n_envs is None:
n_envs = singleton_pool.n_parallel * 4
super().__init__(algo, env)
self.n_envs = n_envs
@overrides
def start_worker(self):
"""Start workers."""
n_envs = self.n_envs
envs = [pickle.loads(pickle.dumps(self.env)) for _ in range(n_envs)]
# Deterministically set environment seeds based on the global seed.
for (i, e) in enumerate(envs):
e.seed(deterministic.get_seed() + i)
self.vec_env = VecEnvExecutor(
envs=envs, max_path_length=self.algo.max_path_length)
self.env_spec = self.env.spec
@overrides
def shutdown_worker(self):
"""Shutdown workers."""
self.vec_env.close()
@overrides
def obtain_samples(self, itr, batch_size=None, whole_paths=True):
"""Obtain samples."""
logger.log('Obtaining samples for iteration %d...' % itr)
if not batch_size:
batch_size = self.algo.max_path_length * self.n_envs
paths = []
n_samples = 0
obses = self.vec_env.reset()
dones = np.asarray([True] * self.vec_env.num_envs)
running_paths = [None] * self.vec_env.num_envs
pbar = ProgBarCounter(batch_size)
policy_time = 0
env_time = 0
process_time = 0
policy = self.algo.policy
import time
while n_samples < batch_size:
t = time.time()
policy.reset(dones)
actions, agent_infos = policy.get_actions(obses)
policy_time += time.time() - t
t = time.time()
next_obses, rewards, dones, env_infos = self.vec_env.step(actions)
env_time += time.time() - t
t = time.time()
agent_infos = tensor_utils.split_tensor_dict_list(agent_infos)
env_infos = tensor_utils.split_tensor_dict_list(env_infos)
if env_infos is None:
env_infos = [dict() for _ in range(self.vec_env.num_envs)]
if agent_infos is None:
agent_infos = [dict() for _ in range(self.vec_env.num_envs)]
for idx, observation, action, reward, env_info, agent_info, done in zip( # noqa: E501
itertools.count(), obses, actions, rewards, env_infos,
agent_infos, dones):
if running_paths[idx] is None:
running_paths[idx] = dict(
observations=[],
actions=[],
rewards=[],
env_infos=[],
agent_infos=[],
)
running_paths[idx]['observations'].append(observation)
running_paths[idx]['actions'].append(action)
running_paths[idx]['rewards'].append(reward)
running_paths[idx]['env_infos'].append(env_info)
running_paths[idx]['agent_infos'].append(agent_info)
if done:
paths.append(
dict(observations=self.env_spec.observation_space.
flatten_n(running_paths[idx]['observations']),
actions=self.env_spec.action_space.flatten_n(
running_paths[idx]['actions']),
rewards=tensor_utils.stack_tensor_list(
running_paths[idx]['rewards']),
env_infos=tensor_utils.stack_tensor_dict_list(
running_paths[idx]['env_infos']),
agent_infos=tensor_utils.stack_tensor_dict_list(
running_paths[idx]['agent_infos'])))
n_samples += len(running_paths[idx]['rewards'])
running_paths[idx] = None
process_time += time.time() - t
pbar.inc(len(obses))
obses = next_obses
pbar.stop()
tabular.record('PolicyExecTime', policy_time)
tabular.record('EnvExecTime', env_time)
tabular.record('ProcessExecTime', process_time)
if whole_paths:
return paths
else:
paths_truncated = truncate_paths(paths, batch_size)
return paths_truncated
class OnPolicyVectorizedSampler(BatchSampler):
"""BatchSampler which uses VecEnvExecutor to run multiple environments.
Args:
algo (garage.np.algos.RLAlgorithm): An algorithm instance.
env (garage.envs.GarageEnv): An environement instance.
n_envs (int): Number of environment instances to setup.
This parameter has effect on sampling performance.
"""
def __init__(self, algo, env, n_envs=None):
if n_envs is None:
n_envs = singleton_pool.n_parallel * 4
super().__init__(algo, env)
self._n_envs = n_envs
self._vec_env = None
self._env_spec = self.env.spec
warnings.warn(
DeprecationWarning(
'OnPolicyVectoriizedSampler is deprecated, and will be '
'removed in the next release. Please use VecWorker and one of '
'the new samplers which implement garage.sampler.Sampler, '
'such as RaySampler.'))
def start_worker(self):
"""Start workers."""
n_envs = self._n_envs
envs = [
cloudpickle.loads(cloudpickle.dumps(self.env))
for _ in range(n_envs)
]
# Deterministically set environment seeds based on the global seed.
seed0 = deterministic.get_seed()
if seed0 is not None:
for (i, e) in enumerate(envs):
e.seed(seed0 + i)
self._vec_env = VecEnvExecutor(
envs=envs, max_path_length=self.algo.max_path_length)
def shutdown_worker(self):
"""Shutdown workers."""
self._vec_env.close()
# pylint: disable=too-many-statements
def obtain_samples(self, itr, batch_size=None, whole_paths=True):
"""Sample the policy for new trajectories.
Args:
itr (int): Iteration number.
batch_size (int): Number of samples to be collected. If None,
it will be default [algo.max_path_length * n_envs].
whole_paths (bool): Whether return all the paths or not. True
by default. It's possible for the paths to have total actual
sample size larger than batch_size, and will be truncated if
this flag is true.
Returns:
list[dict]: Sample paths.
Note:
Each path is a dictionary, with keys and values as following:
* observations: numpy.ndarray with shape [Batch, *obs_dims]
* actions: numpy.ndarray with shape [Batch, *act_dims]
* rewards: numpy.ndarray with shape [Batch, ]
* env_infos: A dictionary with each key representing one
environment info, value being a numpy.ndarray with shape
[Batch, ?]. One example is "ale.lives" for atari
environments.
* agent_infos: A dictionary with each key representing one
agent info, value being a numpy.ndarray with shape
[Batch, ?]. One example is "prev_action", which is used
for recurrent policy as previous action input, merged with
the observation input as the state input.
* dones: numpy.ndarray with shape [Batch, ]
"""
logger.log('Obtaining samples for iteration %d...' % itr)
if not batch_size:
batch_size = self.algo.max_path_length * self._n_envs
paths = []
n_samples = 0
obses = self._vec_env.reset()
dones = np.asarray([True] * self._vec_env.num_envs)
running_paths = [None] * self._vec_env.num_envs
policy_time = 0
env_time = 0
process_time = 0
policy = self.algo.policy
with click.progressbar(length=batch_size, label='Sampling') as pbar:
while n_samples < batch_size:
t = time.time()
policy.reset(dones)
actions, agent_infos = policy.get_actions(obses)
policy_time += time.time() - t
t = time.time()
next_obses, rewards, dones, env_infos = \
self._vec_env.step(actions)
env_time += time.time() - t
t = time.time()
agent_infos = tensor_utils.split_tensor_dict_list(agent_infos)
env_infos = tensor_utils.split_tensor_dict_list(env_infos)
if env_infos is None:
env_infos = [dict() for _ in range(self._vec_env.num_envs)]
if agent_infos is None:
agent_infos = [
dict() for _ in range(self._vec_env.num_envs)
]
for idx, observation, action, reward, env_info, agent_info, done in zip( # noqa: E501
itertools.count(), obses, actions, rewards, env_infos,
agent_infos, dones):
if running_paths[idx] is None:
running_paths[idx] = dict(observations=[],
actions=[],
rewards=[],
env_infos=[],
agent_infos=[],
dones=[])
running_paths[idx]['observations'].append(observation)
running_paths[idx]['actions'].append(action)
running_paths[idx]['rewards'].append(reward)
running_paths[idx]['env_infos'].append(env_info)
running_paths[idx]['agent_infos'].append(agent_info)
running_paths[idx]['dones'].append(done)
if done:
obs = np.asarray(running_paths[idx]['observations'])
actions = np.asarray(running_paths[idx]['actions'])
paths.append(
dict(observations=obs,
actions=actions,
rewards=np.asarray(
running_paths[idx]['rewards']),
env_infos=tensor_utils.stack_tensor_dict_list(
running_paths[idx]['env_infos']),
agent_infos=tensor_utils.
stack_tensor_dict_list(
running_paths[idx]['agent_infos']),
dones=np.asarray(
running_paths[idx]['dones'])))
n_samples += len(running_paths[idx]['rewards'])
running_paths[idx] = None
process_time += time.time() - t
pbar.update(len(obses))
obses = next_obses
tabular.record('PolicyExecTime', policy_time)
tabular.record('EnvExecTime', env_time)
tabular.record('ProcessExecTime', process_time)
return paths if whole_paths else truncate_paths(paths, batch_size)
class OnPolicyVectorizedSampler(BatchSampler):
"""BatchSampler which uses VecEnvExecutor to run multiple environments.
Args:
algo (garage.np.algos.RLAlgorithm): An algorithm instance.
env (garage.envs.GarageEnv): An environement instance.
n_envs (int): Number of environment instances to setup.
This parameter has effect on sampling performance.
"""
def __init__(self, algo, env, n_envs=None):
if n_envs is None:
n_envs = singleton_pool.n_parallel * 4
super().__init__(algo, env)
self._n_envs = n_envs
self._vec_env = None
self._env_spec = self.env.spec
def start_worker(self):
"""Start workers."""
n_envs = self._n_envs
envs = [pickle.loads(pickle.dumps(self.env)) for _ in range(n_envs)]
# Deterministically set environment seeds based on the global seed.
seed0 = deterministic.get_seed()
if seed0 is not None:
for (i, e) in enumerate(envs):
e.seed(seed0 + i)
self._vec_env = VecEnvExecutor(
envs=envs, max_path_length=self.algo.max_path_length)
def shutdown_worker(self):
"""Shutdown workers."""
self._vec_env.close()
# pylint: disable=too-many-statements
def obtain_samples(self, itr, batch_size=None, whole_paths=True):
"""Sample the policy for new trajectories.
Args:
itr (int): Iteration number.
batch_size (int): Number of samples to be collected. If None,
it will be default [algo.max_path_length * n_envs].
whole_paths (bool): Whether return all the paths or not. True
by default. It's possible for the paths to have total actual
sample size larger than batch_size, and will be truncated if
this flag is true.
Returns:
list[dict]: Sample paths, each path with key
* observations: (numpy.ndarray)
* actions: (numpy.ndarray)
* rewards: (numpy.ndarray)
* agent_infos: (dict)
* env_infos: (dict)
"""
logger.log('Obtaining samples for iteration %d...' % itr)
if not batch_size:
batch_size = self.algo.max_path_length * self._n_envs
paths = []
n_samples = 0
obses = self._vec_env.reset()
dones = np.asarray([True] * self._vec_env.num_envs)
running_paths = [None] * self._vec_env.num_envs
pbar = ProgBarCounter(batch_size)
policy_time = 0
env_time = 0
process_time = 0
policy = self.algo.policy
while n_samples < batch_size:
t = time.time()
policy.reset(dones)
actions, agent_infos = policy.get_actions(obses)
policy_time += time.time() - t
t = time.time()
next_obses, rewards, dones, env_infos = self._vec_env.step(actions)
env_time += time.time() - t
t = time.time()
agent_infos = tensor_utils.split_tensor_dict_list(agent_infos)
env_infos = tensor_utils.split_tensor_dict_list(env_infos)
if env_infos is None:
env_infos = [dict() for _ in range(self._vec_env.num_envs)]
if agent_infos is None:
agent_infos = [dict() for _ in range(self._vec_env.num_envs)]
for idx, observation, action, reward, env_info, agent_info, done in zip( # noqa: E501
itertools.count(), obses, actions, rewards, env_infos,
agent_infos, dones):
if running_paths[idx] is None:
running_paths[idx] = dict(
observations=[],
actions=[],
rewards=[],
env_infos=[],
agent_infos=[],
)
running_paths[idx]['observations'].append(observation)
running_paths[idx]['actions'].append(action)
running_paths[idx]['rewards'].append(reward)
running_paths[idx]['env_infos'].append(env_info)
running_paths[idx]['agent_infos'].append(agent_info)
if done:
obs = np.asarray(running_paths[idx]['observations'])
actions = np.asarray(running_paths[idx]['actions'])
paths.append(
dict(observations=obs,
actions=actions,
rewards=np.asarray(running_paths[idx]['rewards']),
env_infos=tensor_utils.stack_tensor_dict_list(
running_paths[idx]['env_infos']),
agent_infos=tensor_utils.stack_tensor_dict_list(
running_paths[idx]['agent_infos'])))
n_samples += len(running_paths[idx]['rewards'])
running_paths[idx] = None
process_time += time.time() - t
pbar.inc(len(obses))
obses = next_obses
pbar.stop()
tabular.record('PolicyExecTime', policy_time)
tabular.record('EnvExecTime', env_time)
tabular.record('ProcessExecTime', process_time)
return paths if whole_paths else truncate_paths(paths, batch_size)
class OffPolicyVectorizedSampler(BatchSampler):
"""This class implements OffPolicyVectorizedSampler.
Args:
algo (garage.np.RLAlgorithm): Algorithm.
env (garage.envs.GarageEnv): Environment.
n_envs (int): Number of parallel environments managed by sampler.
no_reset (bool): Reset environment between samples or not.
"""
def __init__(self, algo, env, n_envs=None, no_reset=True):
if n_envs is None:
n_envs = int(algo.rollout_batch_size)
super().__init__(algo, env)
self._n_envs = n_envs
self._no_reset = no_reset
self._vec_env = None
self._env_spec = self.env.spec
self._last_obses = None
self._last_uncounted_discount = [0] * n_envs
self._last_running_length = [0] * n_envs
self._last_success_count = [0] * n_envs
warnings.warn(
DeprecationWarning(
'OffPolicyVectoriizedSampler is deprecated, and will be '
'removed in the next release. Please use VecWorker and one of '
'the new samplers which implement garage.sampler.Sampler, '
'such as RaySampler.'))
def start_worker(self):
"""Initialize the sampler."""
n_envs = self._n_envs
envs = [pickle.loads(pickle.dumps(self.env)) for _ in range(n_envs)]
# Deterministically set environment seeds based on the global seed.
seed0 = deterministic.get_seed()
if seed0 is not None:
for (i, e) in enumerate(envs):
e.seed(seed0 + i)
self._vec_env = VecEnvExecutor(
envs=envs, max_path_length=self.algo.max_path_length)
def shutdown_worker(self):
"""Terminate workers if necessary."""
self._vec_env.close()
# pylint: disable=too-many-branches, too-many-statements
def obtain_samples(self, itr, batch_size=None, whole_paths=True):
"""Collect samples for the given iteration number.
Args:
itr(int): Iteration number.
batch_size(int): Number of environment interactions in one batch.
whole_paths(bool): Not effective. Only keep here to comply
with base class.
Returns:
list: A list of paths.
"""
assert batch_size is not None
paths = []
if not self._no_reset or self._last_obses is None:
obses = self._vec_env.reset()
else:
obses = self._last_obses
completes = np.asarray([True] * self._vec_env.num_envs)
running_paths = [None] * self._vec_env.num_envs
n_samples = 0
policy = self.algo.policy
if self.algo.es:
self.algo.es.reset()
while n_samples < batch_size:
policy.reset(completes)
obs_space = self.algo.env_spec.observation_space
input_obses = obs_space.flatten_n(obses)
if self.algo.es:
actions, agent_infos = self.algo.es.get_actions(
itr, input_obses, self.algo.policy)
else:
actions, agent_infos = self.algo.policy.get_actions(
input_obses)
next_obses, rewards, dones, env_infos = \
self._vec_env.step(actions)
completes = env_infos['vec_env_executor.complete']
self._last_obses = next_obses
agent_infos = tensor_utils.split_tensor_dict_list(agent_infos)
env_infos = tensor_utils.split_tensor_dict_list(env_infos)
n_samples += len(next_obses)
if agent_infos is None:
agent_infos = [dict() for _ in range(self._vec_env.num_envs)]
if env_infos is None:
env_infos = [dict() for _ in range(self._vec_env.num_envs)]
self.algo.replay_buffer.add_transitions(
observation=obses,
action=actions,
reward=rewards,
terminal=dones,
next_observation=next_obses,
)
for idx, reward, env_info, done in zip(itertools.count(), rewards,
env_infos, dones):
if running_paths[idx] is None:
running_paths[idx] = dict(
rewards=[],
env_infos=[],
dones=[],
undiscounted_return=self._last_uncounted_discount[idx],
# running_length: Length of path up to now
# Note that running_length is not len(rewards)
# Because a path may not be complete in one batch
running_length=self._last_running_length[idx],
success_count=self._last_success_count[idx])
running_paths[idx]['rewards'].append(reward)
running_paths[idx]['env_infos'].append(env_info)
running_paths[idx]['dones'].append(done)
running_paths[idx]['running_length'] += 1
running_paths[idx]['undiscounted_return'] += reward
running_paths[idx]['success_count'] += env_info.get(
'is_success') or 0
self._last_uncounted_discount[idx] += reward
self._last_success_count[idx] += env_info.get(
'is_success') or 0
self._last_running_length[idx] += 1
if done or n_samples >= batch_size:
paths.append(
dict(
rewards=np.asarray(running_paths[idx]['rewards']),
dones=np.asarray(running_paths[idx]['dones']),
env_infos=tensor_utils.stack_tensor_dict_list(
running_paths[idx]['env_infos']),
running_length=running_paths[idx]
['running_length'],
undiscounted_return=running_paths[idx]
['undiscounted_return'],
success_count=running_paths[idx]['success_count']))
running_paths[idx] = None
if done:
self._last_running_length[idx] = 0
self._last_success_count[idx] = 0
self._last_uncounted_discount[idx] = 0
if self.algo.es:
self.algo.es.reset()
obses = next_obses
return paths
class OffPolicyVectorizedSampler(BatchSampler):
"""This class implements OffPolicyVectorizedSampler.
Args:
algo (garage.np.RLAlgorithm): Algorithm.
env (garage.envs.GarageEnv): Environment.
n_envs (int): Number of parallel environments managed by sampler.
no_reset (bool): Reset environment between samples or not.
"""
def __init__(self, algo, env, n_envs=None, no_reset=True):
if n_envs is None:
n_envs = int(algo.rollout_batch_size)
super().__init__(algo, env)
self.n_envs = n_envs
self.no_reset = no_reset
self._last_obses = None
self._last_uncounted_discount = [0] * n_envs
self._last_running_length = [0] * n_envs
self._last_success_count = [0] * n_envs
@overrides
def start_worker(self):
"""Initialize the sampler."""
n_envs = self.n_envs
envs = [pickle.loads(pickle.dumps(self.env)) for _ in range(n_envs)]
self.vec_env = VecEnvExecutor(
envs=envs, max_path_length=self.algo.max_path_length)
self.env_spec = self.env.spec
@overrides
def shutdown_worker(self):
"""Terminate workers if necessary."""
self.vec_env.close()
@overrides
def obtain_samples(self, itr, batch_size):
"""Collect samples for the given iteration number.
Args:
itr(int): Iteration number.
batch_size(int): Number of environment interactions in one batch.
Returns:
list: A list of paths.
"""
paths = []
if not self.no_reset or self._last_obses is None:
obses = self.vec_env.reset()
else:
obses = self._last_obses
dones = np.asarray([True] * self.vec_env.num_envs)
running_paths = [None] * self.vec_env.num_envs
n_samples = 0
policy = self.algo.policy
if self.algo.es:
self.algo.es.reset()
while n_samples < batch_size:
policy.reset(dones)
if self.algo.input_include_goal:
obs = [obs['observation'] for obs in obses]
d_g = [obs['desired_goal'] for obs in obses]
a_g = [obs['achieved_goal'] for obs in obses]
input_obses = np.concatenate((obs, d_g), axis=-1)
else:
input_obses = obses
obs_normalized = tensor_utils.normalize_pixel_batch(
self.env_spec, input_obses)
if self.algo.es:
actions, agent_infos = self.algo.es.get_actions(
itr, obs_normalized, self.algo.policy)
else:
actions, agent_infos = self.algo.policy.get_actions(
obs_normalized)
next_obses, rewards, dones, env_infos = self.vec_env.step(actions)
self._last_obses = next_obses
agent_infos = tensor_utils.split_tensor_dict_list(agent_infos)
env_infos = tensor_utils.split_tensor_dict_list(env_infos)
n_samples += len(next_obses)
if agent_infos is None:
agent_infos = [dict() for _ in range(self.vec_env.num_envs)]
if env_infos is None:
env_infos = [dict() for _ in range(self.vec_env.num_envs)]
if self.algo.input_include_goal:
self.algo.replay_buffer.add_transitions(
observation=obs,
action=actions,
goal=d_g,
achieved_goal=a_g,
terminal=dones,
next_observation=[
next_obs['observation'] for next_obs in next_obses
],
next_achieved_goal=[
next_obs['achieved_goal'] for next_obs in next_obses
],
)
else:
self.algo.replay_buffer.add_transitions(
observation=obses,
action=actions,
reward=rewards * self.algo.reward_scale,
terminal=dones,
next_observation=next_obses,
)
for idx, reward, env_info, done in zip(itertools.count(), rewards,
env_infos, dones):
if running_paths[idx] is None:
running_paths[idx] = dict(
rewards=[],
env_infos=[],
dones=[],
undiscounted_return=self._last_uncounted_discount[idx],
# running_length: Length of path up to now
# Note that running_length is not len(rewards)
# Because a path may not be complete in one batch
running_length=self._last_running_length[idx],
success_count=self._last_success_count[idx])
running_paths[idx]['rewards'].append(reward)
running_paths[idx]['env_infos'].append(env_info)
running_paths[idx]['dones'].append(done)
running_paths[idx]['running_length'] += 1
running_paths[idx]['undiscounted_return'] += reward
running_paths[idx]['success_count'] += env_info.get(
'is_success') or 0
self._last_uncounted_discount[idx] += reward
self._last_success_count[idx] += env_info.get(
'is_success') or 0
self._last_running_length[idx] += 1
if done or n_samples >= batch_size:
paths.append(
dict(
rewards=tensor_utils.stack_tensor_list(
running_paths[idx]['rewards']),
dones=tensor_utils.stack_tensor_list(
running_paths[idx]['dones']),
env_infos=tensor_utils.stack_tensor_dict_list(
running_paths[idx]['env_infos']),
running_length=running_paths[idx]
['running_length'],
undiscounted_return=running_paths[idx]
['undiscounted_return'],
success_count=running_paths[idx]['success_count']))
running_paths[idx] = None
if done:
self._last_running_length[idx] = 0
self._last_success_count[idx] = 0
self._last_uncounted_discount[idx] = 0
if self.algo.es:
self.algo.es.reset()
obses = next_obses
return paths
class RL2Sampler(BaseSampler):
"""Sampler which uses VecEnvExecutor to run multiple environments.
This sampler is for RL^2. See https://arxiv.org/pdf/1611.02779.pdf.
In RL^2, there are n environments/tasks and paths in each of them
will be concatenated at some point and fed to the policy.
This sampler uses an OrderedDict, instead of a List, to keep track
of the paths for each environment/task.
Args:
algo (garage.np.algos.RLAlgorithm): An algorithm instance.
env (garage.envs.GarageEnv): Environement to sample from.
meta_batch_size (int): Meta batch size for sampling. If it is
larger than n_envs, it must be a multiple of n_envs so it can be
evenly distributed among environments.
n_envs (int): Number of environment instances for sampling. It it is
larger than meta_batch_size, it must be a multiple of
meta_batch_size so batch can be evenly distributed among
environments.
Raises:
ValueError: If meta_batch_size > n_envs and meta_batch_size is not
a multiple of n_envs, or if n_envs > meta_batch_size and n_envs
is not a multiple of meta_batch_size.
"""
def __init__(self, algo, env, meta_batch_size, n_envs=None):
super().__init__(algo, env)
if n_envs is None:
n_envs = singleton_pool.n_parallel * 4
self._n_envs = n_envs
self._meta_batch_size = meta_batch_size
self._vec_env = None
self._envs_per_worker = None
self._vec_envs_indices = None
if self._meta_batch_size > self._n_envs:
if self._meta_batch_size % self._n_envs != 0:
raise ValueError(
'meta_batch_size must be a multiple of n_envs')
self._envs_per_worker = 1
self._vec_envs_indices = np.split(np.arange(self._meta_batch_size),
self._n_envs)
if self._n_envs >= self._meta_batch_size:
if self._n_envs % self._meta_batch_size != 0:
raise ValueError(
'n_envs must be a multiple of meta_batch_size')
self._envs_per_worker = self._n_envs // self._meta_batch_size
self._vec_envs_indices = [np.arange(self._meta_batch_size)]
def start_worker(self):
"""This function is deprecated."""
def shutdown_worker(self):
"""Shutdown workers."""
self._vec_env.close()
def _setup_worker(self, env_indices, tasks):
"""Setup workers.
Args:
env_indices (List[Int]): Indices of environments to be assigned
to workers for sampling.
tasks (List[dict]): List of tasks to assign.
"""
if self._vec_env is not None:
self._vec_env.close()
vec_envs = []
for env_ind in env_indices:
for _ in range(self._envs_per_worker):
vec_env = copy.deepcopy(self.env)
vec_env.set_task(tasks[env_ind])
vec_envs.append(vec_env)
seed0 = deterministic.get_seed()
if seed0 is not None:
for (i, e) in enumerate(vec_envs):
e.seed(seed0 + i)
self._vec_env = VecEnvExecutor(
envs=vec_envs, max_path_length=self.algo.max_path_length)
# pylint: disable=too-many-statements
def obtain_samples(self, itr, batch_size=None, whole_paths=True):
"""Sample the policy for new trajectories.
If batch size is not specified, episode per task by default is 1 so
batch size will be meta_batch_size * max_path_length.
When number of workers are less than meta batch size, sampling will
be performed for each of self._vec_envs_indices in series. The
i-th value of self._vec_envs_indices represents the indices of the
environments/tasks to be sampled for the i-th iteration.
Args:
itr (int): Iteration number.
batch_size (int): Number of samples to be collected. If None,
it will be default [algo.max_path_length * n_envs].
whole_paths (bool): Whether return all the paths or not. True
by default. It's possible for the paths to have total actual
sample size larger than batch_size, and will be truncated if
this flag is true.
Returns:
OrderedDict: Sample paths. Key represents the index of the
environment/task and value represents all the paths sampled
from that particular environment/task.
Note:
Each path is a dictionary, with keys and values as following:
* observations: numpy.ndarray with shape :math:`[N, S^*]`
* actions: numpy.ndarray with shape :math:`[N, S^*]`
* rewards: numpy.ndarray with shape :math:`[N, S^*]`
* dones: numpy.ndarray with shape :math:`[N, S^*]`
* env_infos: A dictionary with each key representing one
environment info, value being a numpy.ndarray with shape
:math:`[N, S^*]`. One example is "ale.lives" for atari
environments.
* agent_infos: A dictionary with each key representing one
agent info, value being a numpy.ndarray with shape
:math:`[N, S^*]`. One example is "prev_action", which is used
for recurrent policy as previous action input, merged with
the observation input as the state input.
"""
logger.log('Obtaining samples for iteration %d...' % itr)
if batch_size is None:
batch_size = self.algo.max_path_length * self._meta_batch_size
paths = []
tasks = self.env.sample_tasks(self._meta_batch_size)
# Start main loop
batch_size_per_loop = batch_size // len(self._vec_envs_indices)
for vec_envs_indices in self._vec_envs_indices:
self._setup_worker(vec_envs_indices, tasks)
n_samples = 0
obses = self._vec_env.reset()
dones = np.asarray([True] * self._vec_env.num_envs)
running_paths = [None] * self._vec_env.num_envs
pbar = ProgBarCounter(batch_size)
policy_time = 0
env_time = 0
process_time = 0
policy = self.algo.policy
# Only reset policies at the beginning of a meta batch
policy.reset(dones)
while n_samples < batch_size_per_loop:
t = time.time()
actions, agent_infos = policy.get_actions(obses)
policy_time += time.time() - t
t = time.time()
next_obses, rewards, dones, env_infos = self._vec_env.step(
actions)
env_time += time.time() - t
t = time.time()
agent_infos = tensor_utils.split_tensor_dict_list(agent_infos)
env_infos = tensor_utils.split_tensor_dict_list(env_infos)
if env_infos is None:
env_infos = [dict() for _ in range(self._vec_env.num_envs)]
if agent_infos is None:
agent_infos = [
dict() for _ in range(self._vec_env.num_envs)
]
for idx, observation, action, reward, env_info, agent_info, done in zip( # noqa: E501
itertools.count(), obses, actions, rewards, env_infos,
agent_infos, dones):
if running_paths[idx] is None:
running_paths[idx] = dict(
observations=[],
actions=[],
rewards=[],
dones=[],
env_infos=[],
agent_infos=[],
)
running_paths[idx]['observations'].append(observation)
running_paths[idx]['actions'].append(action)
running_paths[idx]['rewards'].append(reward)
running_paths[idx]['dones'].append(done)
running_paths[idx]['env_infos'].append(env_info)
running_paths[idx]['agent_infos'].append(agent_info)
if done:
obs = np.asarray(running_paths[idx]['observations'])
actions = np.asarray(running_paths[idx]['actions'])
paths.append(
dict(observations=obs,
actions=actions,
rewards=np.asarray(
running_paths[idx]['rewards']),
dones=np.asarray(running_paths[idx]['dones']),
env_infos=tensor_utils.stack_tensor_dict_list(
running_paths[idx]['env_infos']),
agent_infos=tensor_utils.
stack_tensor_dict_list(
running_paths[idx]['agent_infos']),
batch_idx=idx))
n_samples += len(running_paths[idx]['rewards'])
running_paths[idx] = None
process_time += time.time() - t
pbar.inc(len(obses))
obses = next_obses
pbar.stop()
tabular.record('PolicyExecTime', policy_time)
tabular.record('EnvExecTime', env_time)
tabular.record('ProcessExecTime', process_time)
return paths if whole_paths else truncate_paths(paths, batch_size)