lerobot/lerobot/scripts/server/learner_server.py

633 lines
24 KiB
Python

#!/usr/bin/env python
# Copyright 2024 The HuggingFace Inc. team.
# All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import io
import logging
import pickle
import queue
import shutil
import time
from pprint import pformat
from threading import Lock, Thread
import grpc
# Import generated stubs
import hilserl_pb2 # type: ignore
import hilserl_pb2_grpc # type: ignore
import hydra
import torch
from deepdiff import DeepDiff
from omegaconf import DictConfig, OmegaConf
from termcolor import colored
from torch import nn
from torch.optim.optimizer import Optimizer
from lerobot.common.datasets.factory import make_dataset
# TODO: Remove the import of maniskill
from lerobot.common.datasets.lerobot_dataset import LeRobotDataset
from lerobot.common.logger import Logger, log_output_dir
from lerobot.common.policies.factory import make_policy
from lerobot.common.policies.sac.modeling_sac import SACPolicy
from lerobot.common.utils.utils import (
format_big_number,
get_global_random_state,
get_safe_torch_device,
init_hydra_config,
init_logging,
set_global_random_state,
set_global_seed,
)
from lerobot.scripts.server.buffer import (
ReplayBuffer,
concatenate_batch_transitions,
move_state_dict_to_device,
move_transition_to_device,
)
logging.basicConfig(level=logging.INFO)
transition_queue = queue.Queue()
interaction_message_queue = queue.Queue()
def handle_resume_logic(cfg: DictConfig, out_dir: str) -> DictConfig:
if not cfg.resume:
if Logger.get_last_checkpoint_dir(out_dir).exists():
raise RuntimeError(
f"Output directory {Logger.get_last_checkpoint_dir(out_dir)} already exists. "
"Use `resume=true` to resume training."
)
return cfg
# if resume == True
checkpoint_dir = Logger.get_last_checkpoint_dir(out_dir)
if not checkpoint_dir.exists():
raise RuntimeError(f"No model checkpoint found in {checkpoint_dir} for resume=True")
checkpoint_cfg_path = str(Logger.get_last_pretrained_model_dir(out_dir) / "config.yaml")
logging.info(
colored(
"Resume=True detected, resuming previous run",
color="yellow",
attrs=["bold"],
)
)
checkpoint_cfg = init_hydra_config(checkpoint_cfg_path)
diff = DeepDiff(OmegaConf.to_container(checkpoint_cfg), OmegaConf.to_container(cfg))
if "values_changed" in diff and "root['resume']" in diff["values_changed"]:
del diff["values_changed"]["root['resume']"]
if len(diff) > 0:
logging.warning(
f"Differences between the checkpoint config and the provided config detected: \n{pformat(diff)}\n"
"Checkpoint configuration takes precedence."
)
checkpoint_cfg.resume = True
return checkpoint_cfg
def load_training_state(
cfg: DictConfig,
logger: Logger,
optimizers: Optimizer | dict,
):
if not cfg.resume:
return None, None
training_state = torch.load(logger.last_checkpoint_dir / logger.training_state_file_name)
if isinstance(training_state["optimizer"], dict):
assert set(training_state["optimizer"].keys()) == set(optimizers.keys())
for k, v in training_state["optimizer"].items():
optimizers[k].load_state_dict(v)
else:
optimizers.load_state_dict(training_state["optimizer"])
set_global_random_state({k: training_state[k] for k in get_global_random_state()})
return training_state["step"], training_state["interaction_step"]
def log_training_info(cfg: DictConfig, out_dir: str, policy: nn.Module) -> None:
num_learnable_params = sum(p.numel() for p in policy.parameters() if p.requires_grad)
num_total_params = sum(p.numel() for p in policy.parameters())
log_output_dir(out_dir)
logging.info(f"{cfg.env.task=}")
logging.info(f"{cfg.training.online_steps=}")
logging.info(f"{num_learnable_params=} ({format_big_number(num_learnable_params)})")
logging.info(f"{num_total_params=} ({format_big_number(num_total_params)})")
def initialize_replay_buffer(cfg: DictConfig, logger: Logger, device: str) -> ReplayBuffer:
if not cfg.resume:
return ReplayBuffer(
capacity=cfg.training.online_buffer_capacity,
device=device,
state_keys=cfg.policy.input_shapes.keys(),
)
dataset = LeRobotDataset(
repo_id=cfg.dataset_repo_id, local_files_only=True, root=logger.log_dir / "dataset"
)
return ReplayBuffer.from_lerobot_dataset(
lerobot_dataset=dataset,
capacity=cfg.training.online_buffer_capacity,
device=device,
state_keys=cfg.policy.input_shapes.keys(),
)
def start_learner_threads(
cfg: DictConfig,
device: str,
replay_buffer: ReplayBuffer,
offline_replay_buffer: ReplayBuffer,
batch_size: int,
optimizers: dict,
policy: SACPolicy,
policy_lock: Lock,
logger: Logger,
resume_optimization_step: int | None = None,
resume_interaction_step: int | None = None,
) -> None:
actor_ip = cfg.actor_learner_config.actor_ip
port = cfg.actor_learner_config.port
server_thread = Thread(
target=stream_transitions_from_actor,
args=(
actor_ip,
port,
),
daemon=True,
)
transition_thread = Thread(
target=add_actor_information_and_train,
daemon=True,
args=(
cfg,
device,
replay_buffer,
offline_replay_buffer,
batch_size,
optimizers,
policy,
policy_lock,
logger,
resume_optimization_step,
resume_interaction_step,
),
)
param_push_thread = Thread(
target=learner_push_parameters,
args=(policy, policy_lock, actor_ip, port, 15),
daemon=True,
)
server_thread.start()
transition_thread.start()
param_push_thread.start()
param_push_thread.join()
transition_thread.join()
server_thread.join()
def stream_transitions_from_actor(host="127.0.0.1", port=50051):
"""
Runs a gRPC client that listens for transition and interaction messages from an Actor service.
This function establishes a gRPC connection with the given `host` and `port`, then continuously
streams transition data from the `ActorServiceStub`. The received transition data is deserialized
and stored in a queue (`transition_queue`). Similarly, interaction messages are also deserialized
and stored in a separate queue (`interaction_message_queue`).
Args:
host (str, optional): The IP address or hostname of the gRPC server. Defaults to `"127.0.0.1"`.
port (int, optional): The port number on which the gRPC server is running. Defaults to `50051`.
"""
# NOTE: This is waiting for the handshake to be done
# In the future we will do it in a canonical way with a proper handshake
time.sleep(10)
channel = grpc.insecure_channel(
f"{host}:{port}",
options=[("grpc.max_send_message_length", -1), ("grpc.max_receive_message_length", -1)],
)
stub = hilserl_pb2_grpc.ActorServiceStub(channel)
for response in stub.StreamTransition(hilserl_pb2.Empty()):
if response.HasField("transition"):
buffer = io.BytesIO(response.transition.transition_bytes)
transition = torch.load(buffer)
transition_queue.put(transition)
if response.HasField("interaction_message"):
content = pickle.loads(response.interaction_message.interaction_message_bytes)
interaction_message_queue.put(content)
def learner_push_parameters(
policy: nn.Module, policy_lock: Lock, actor_host="127.0.0.1", actor_port=50052, seconds_between_pushes=5
):
"""
As a client, connect to the Actor's gRPC server (ActorService)
and periodically push new parameters.
"""
time.sleep(10)
channel = grpc.insecure_channel(
f"{actor_host}:{actor_port}",
options=[("grpc.max_send_message_length", -1), ("grpc.max_receive_message_length", -1)],
)
actor_stub = hilserl_pb2_grpc.ActorServiceStub(channel)
while True:
with policy_lock:
params_dict = policy.actor.state_dict()
if policy.config.vision_encoder_name is not None:
if policy.config.freeze_vision_encoder:
params_dict: dict[str, torch.Tensor] = {
k: v for k, v in params_dict.items() if not k.startswith("encoder.")
}
else:
raise NotImplementedError(
"Vision encoder is not frozen, we need to send the full model over the network which requires chunking the model."
)
params_dict = move_state_dict_to_device(params_dict, device="cpu")
# Serialize
buf = io.BytesIO()
torch.save(params_dict, buf)
params_bytes = buf.getvalue()
# Push them to the Actor's "SendParameters" method
logging.info("[LEARNER] Publishing parameters to the Actor")
response = actor_stub.SendParameters(hilserl_pb2.Parameters(parameter_bytes=params_bytes)) # noqa: F841
time.sleep(seconds_between_pushes)
def check_nan_in_transition(observations: torch.Tensor, actions: torch.Tensor, next_state: torch.Tensor):
for k in observations:
if torch.isnan(observations[k]).any():
logging.error(f"observations[{k}] contains NaN values")
for k in next_state:
if torch.isnan(next_state[k]).any():
logging.error(f"next_state[{k}] contains NaN values")
if torch.isnan(actions).any():
logging.error("actions contains NaN values")
def add_actor_information_and_train(
cfg,
device: str,
replay_buffer: ReplayBuffer,
offline_replay_buffer: ReplayBuffer,
batch_size: int,
optimizers: dict[str, torch.optim.Optimizer],
policy: nn.Module,
policy_lock: Lock,
logger: Logger,
resume_optimization_step: int | None = None,
resume_interaction_step: int | None = None,
):
"""
Handles data transfer from the actor to the learner, manages training updates,
and logs training progress in an online reinforcement learning setup.
This function continuously:
- Transfers transitions from the actor to the replay buffer.
- Logs received interaction messages.
- Ensures training begins only when the replay buffer has a sufficient number of transitions.
- Samples batches from the replay buffer and performs multiple critic updates.
- Periodically updates the actor, critic, and temperature optimizers.
- Logs training statistics, including loss values and optimization frequency.
**NOTE:**
- This function performs multiple responsibilities (data transfer, training, and logging).
It should ideally be split into smaller functions in the future.
- Due to Python's **Global Interpreter Lock (GIL)**, running separate threads for different tasks
significantly reduces performance. Instead, this function executes all operations in a single thread.
Args:
cfg: Configuration object containing hyperparameters.
device (str): The computing device (`"cpu"` or `"cuda"`).
replay_buffer (ReplayBuffer): The primary replay buffer storing online transitions.
offline_replay_buffer (ReplayBuffer): An additional buffer for offline transitions.
batch_size (int): The number of transitions to sample per training step.
optimizers (Dict[str, torch.optim.Optimizer]): A dictionary of optimizers (`"actor"`, `"critic"`, `"temperature"`).
policy (nn.Module): The reinforcement learning policy with critic, actor, and temperature parameters.
policy_lock (Lock): A threading lock to ensure safe policy updates.
logger (Logger): Logger instance for tracking training progress.
resume_optimization_step (int | None): In the case of resume training, start from the last optimization step reached.
resume_interaction_step (int | None): In the case of resume training, shift the interaction step with the last saved step in order to not break logging.
"""
# NOTE: This function doesn't have a single responsibility, it should be split into multiple functions
# in the future. The reason why we did that is the GIL in Python. It's super slow the performance
# are divided by 200. So we need to have a single thread that does all the work.
time.time()
logging.info("Starting learner thread")
interaction_message, transition = None, None
optimization_step = resume_optimization_step if resume_optimization_step is not None else 0
interaction_step_shift = resume_interaction_step if resume_interaction_step is not None else 0
while True:
while not transition_queue.empty():
transition_list = transition_queue.get()
for transition in transition_list:
transition = move_transition_to_device(transition, device=device)
replay_buffer.add(**transition)
if transition.get("complementary_info", {}).get("is_intervention"):
offline_replay_buffer.add(**transition)
while not interaction_message_queue.empty():
interaction_message = interaction_message_queue.get()
# If cfg.resume, shift the interaction step with the last checkpointed step in order to not break the logging
interaction_message["Interaction step"] += interaction_step_shift
logger.log_dict(interaction_message, mode="train", custom_step_key="Interaction step")
logging.info(f"Interaction message: {interaction_message}")
if len(replay_buffer) < cfg.training.online_step_before_learning:
continue
# logging.info(f"Size of replay buffer: {len(replay_buffer)}")
# logging.info(f"Size of offline replay buffer: {len(offline_replay_buffer)}")
time_for_one_optimization_step = time.time()
for _ in range(cfg.policy.utd_ratio - 1):
batch = replay_buffer.sample(batch_size)
if cfg.dataset_repo_id is not None:
batch_offline = offline_replay_buffer.sample(batch_size)
batch = concatenate_batch_transitions(batch, batch_offline)
actions = batch["action"]
rewards = batch["reward"]
observations = batch["state"]
next_observations = batch["next_state"]
done = batch["done"]
check_nan_in_transition(observations=observations, actions=actions, next_state=next_observations)
with policy_lock:
loss_critic = policy.compute_loss_critic(
observations=observations,
actions=actions,
rewards=rewards,
next_observations=next_observations,
done=done,
)
optimizers["critic"].zero_grad()
loss_critic.backward()
optimizers["critic"].step()
batch = replay_buffer.sample(batch_size)
if cfg.dataset_repo_id is not None:
batch_offline = offline_replay_buffer.sample(batch_size)
batch = concatenate_batch_transitions(
left_batch_transitions=batch, right_batch_transition=batch_offline
)
actions = batch["action"]
rewards = batch["reward"]
observations = batch["state"]
next_observations = batch["next_state"]
done = batch["done"]
check_nan_in_transition(observations=observations, actions=actions, next_state=next_observations)
with policy_lock:
loss_critic = policy.compute_loss_critic(
observations=observations,
actions=actions,
rewards=rewards,
next_observations=next_observations,
done=done,
)
optimizers["critic"].zero_grad()
loss_critic.backward()
optimizers["critic"].step()
training_infos = {}
training_infos["loss_critic"] = loss_critic.item()
if optimization_step % cfg.training.policy_update_freq == 0:
for _ in range(cfg.training.policy_update_freq):
with policy_lock:
loss_actor = policy.compute_loss_actor(observations=observations)
optimizers["actor"].zero_grad()
loss_actor.backward()
optimizers["actor"].step()
training_infos["loss_actor"] = loss_actor.item()
loss_temperature = policy.compute_loss_temperature(observations=observations)
optimizers["temperature"].zero_grad()
loss_temperature.backward()
optimizers["temperature"].step()
training_infos["loss_temperature"] = loss_temperature.item()
policy.update_target_networks()
if optimization_step % cfg.training.log_freq == 0:
logger.log_dict(training_infos, step=optimization_step, mode="train")
time_for_one_optimization_step = time.time() - time_for_one_optimization_step
frequency_for_one_optimization_step = 1 / (time_for_one_optimization_step + 1e-9)
logging.info(f"[LEARNER] Optimization frequency loop [Hz]: {frequency_for_one_optimization_step}")
logger.log_dict(
{"Optimization frequency loop [Hz]": frequency_for_one_optimization_step},
step=optimization_step,
mode="train",
)
optimization_step += 1
if optimization_step % cfg.training.log_freq == 0:
logging.info(f"[LEARNER] Number of optimization step: {optimization_step}")
if cfg.training.save_checkpoint and (
optimization_step % cfg.training.save_freq == 0 or optimization_step == cfg.training.online_steps
):
logging.info(f"Checkpoint policy after step {optimization_step}")
# Note: Save with step as the identifier, and format it to have at least 6 digits but more if
# needed (choose 6 as a minimum for consistency without being overkill).
_num_digits = max(6, len(str(cfg.training.online_steps)))
step_identifier = f"{optimization_step:0{_num_digits}d}"
interaction_step = (
interaction_message["Interaction step"] if interaction_message is not None else 0
)
logger.save_checkpoint(
optimization_step,
policy,
optimizers,
scheduler=None,
identifier=step_identifier,
interaction_step=interaction_step,
)
# TODO : temporarly save replay buffer here, remove later when on the robot
# We want to control this with the keyboard inputs
dataset_dir = logger.log_dir / "dataset"
if dataset_dir.exists() and dataset_dir.is_dir():
shutil.rmtree(
dataset_dir,
)
replay_buffer.to_lerobot_dataset(
cfg.dataset_repo_id, fps=cfg.fps, root=logger.log_dir / "dataset"
)
logging.info("Resume training")
def make_optimizers_and_scheduler(cfg, policy: nn.Module):
"""
Creates and returns optimizers for the actor, critic, and temperature components of a reinforcement learning policy.
This function sets up Adam optimizers for:
- The **actor network**, ensuring that only relevant parameters are optimized.
- The **critic ensemble**, which evaluates the value function.
- The **temperature parameter**, which controls the entropy in soft actor-critic (SAC)-like methods.
It also initializes a learning rate scheduler, though currently, it is set to `None`.
**NOTE:**
- If the encoder is shared, its parameters are excluded from the actor's optimization process.
- The policy's log temperature (`log_alpha`) is wrapped in a list to ensure proper optimization as a standalone tensor.
Args:
cfg: Configuration object containing hyperparameters.
policy (nn.Module): The policy model containing the actor, critic, and temperature components.
Returns:
Tuple[Dict[str, torch.optim.Optimizer], Optional[torch.optim.lr_scheduler._LRScheduler]]:
A tuple containing:
- `optimizers`: A dictionary mapping component names ("actor", "critic", "temperature") to their respective Adam optimizers.
- `lr_scheduler`: Currently set to `None` but can be extended to support learning rate scheduling.
"""
optimizer_actor = torch.optim.Adam(
# NOTE: Handle the case of shared encoder where the encoder weights are not optimized with the gradient of the actor
params=policy.actor.parameters_to_optimize,
lr=policy.config.actor_lr,
)
optimizer_critic = torch.optim.Adam(
params=policy.critic_ensemble.parameters(), lr=policy.config.critic_lr
)
optimizer_temperature = torch.optim.Adam(params=[policy.log_alpha], lr=policy.config.critic_lr)
lr_scheduler = None
optimizers = {
"actor": optimizer_actor,
"critic": optimizer_critic,
"temperature": optimizer_temperature,
}
return optimizers, lr_scheduler
def train(cfg: DictConfig, out_dir: str | None = None, job_name: str | None = None):
if out_dir is None:
raise NotImplementedError()
if job_name is None:
raise NotImplementedError()
init_logging()
logging.info(pformat(OmegaConf.to_container(cfg)))
logger = Logger(cfg, out_dir, wandb_job_name=job_name)
cfg = handle_resume_logic(cfg, out_dir)
set_global_seed(cfg.seed)
device = get_safe_torch_device(cfg.device, log=True)
torch.backends.cudnn.benchmark = True
torch.backends.cuda.matmul.allow_tf32 = True
logging.info("make_policy")
### Instantiate the policy in both the actor and learner processes
### To avoid sending a SACPolicy object through the port, we create a policy intance
### on both sides, the learner sends the updated parameters every n steps to update the actor's parameters
# TODO: At some point we should just need make sac policy
policy_lock = Lock()
policy: SACPolicy = make_policy(
hydra_cfg=cfg,
# dataset_stats=offline_dataset.meta.stats if not cfg.resume else None,
# Hack: But if we do online traning, we do not need dataset_stats
dataset_stats=None,
pretrained_policy_name_or_path=str(logger.last_pretrained_model_dir) if cfg.resume else None,
)
# compile policy
policy = torch.compile(policy)
assert isinstance(policy, nn.Module)
optimizers, lr_scheduler = make_optimizers_and_scheduler(cfg, policy)
resume_optimization_step, resume_interaction_step = load_training_state(cfg, logger, optimizers)
log_training_info(cfg, out_dir, policy)
replay_buffer = initialize_replay_buffer(cfg, logger, device)
batch_size = cfg.training.batch_size
offline_replay_buffer = None
if cfg.dataset_repo_id is not None:
logging.info("make_dataset offline buffer")
offline_dataset = make_dataset(cfg)
logging.info("Convertion to a offline replay buffer")
active_action_dims = [i for i, mask in enumerate(cfg.env.wrapper.joint_masking_action_space) if mask]
offline_replay_buffer = ReplayBuffer.from_lerobot_dataset(
offline_dataset,
device=device,
state_keys=cfg.policy.input_shapes.keys(),
action_mask=active_action_dims,
action_delta=cfg.env.wrapper.delta_action,
)
batch_size: int = batch_size // 2 # We will sample from both replay buffer
start_learner_threads(
cfg,
device,
replay_buffer,
offline_replay_buffer,
batch_size,
optimizers,
policy,
policy_lock,
logger,
resume_optimization_step,
resume_interaction_step,
)
@hydra.main(version_base="1.2", config_name="default", config_path="../../configs")
def train_cli(cfg: dict):
train(
cfg,
out_dir=hydra.core.hydra_config.HydraConfig.get().run.dir,
job_name=hydra.core.hydra_config.HydraConfig.get().job.name,
)
if __name__ == "__main__":
train_cli()