lerobot/lerobot/scripts/server/learner_server.py

446 lines
17 KiB
Python
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

#!/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 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 omegaconf import DictConfig, OmegaConf
from torch import nn
# TODO: Remove the import of maniskill
from lerobot.common.datasets.factory import make_dataset
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_safe_torch_device,
init_logging,
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)
# TODO: Implement it in cleaner way maybe
transition_queue = queue.Queue()
interaction_message_queue = queue.Queue()
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()
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 Actors "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 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,
buffer_lock: Lock,
offline_buffer_lock: Lock,
logger_lock: Lock,
logger: Logger,
):
"""
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.
buffer_lock (Lock): A threading lock to safely access the online replay buffer.
offline_buffer_lock (Lock): A threading lock to safely access the offline replay buffer.
logger_lock (Lock): A threading lock to safely log training metrics.
logger (Logger): Logger instance for tracking training progress.
"""
# 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()
optimization_step = 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)
while not interaction_message_queue.empty():
interaction_message = interaction_message_queue.get()
logger.log_dict(interaction_message, mode="train", custom_step_key="Interaction step")
if len(replay_buffer) < cfg.training.online_step_before_learning:
continue
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"]
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"]
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.debug(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}")
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 actors optimization process.
- The policys 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
)
# We wrap policy log temperature in list because this is a torch tensor and not a nn.Module
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)
logger_lock = Lock()
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()
with logger_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,
device=device,
)
assert isinstance(policy, nn.Module)
optimizers, lr_scheduler = make_optimizers_and_scheduler(cfg, policy)
# TODO: Handle resume
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)})")
buffer_lock = Lock()
replay_buffer = ReplayBuffer(
capacity=cfg.training.online_buffer_capacity, device=device, state_keys=cfg.policy.input_shapes.keys()
)
batch_size = cfg.training.batch_size
offline_buffer_lock = None
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")
offline_replay_buffer = ReplayBuffer.from_lerobot_dataset(
offline_dataset, device=device, state_keys=cfg.policy.input_shapes.keys()
)
offline_buffer_lock = Lock()
batch_size: int = batch_size // 2 # We will sample from both replay buffer
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,
)
server_thread.start()
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,
buffer_lock,
offline_buffer_lock,
logger_lock,
logger,
),
)
transition_thread.start()
param_push_thread = Thread(
target=learner_push_parameters,
args=(policy, policy_lock, actor_ip, port, 15),
daemon=True,
)
param_push_thread.start()
transition_thread.join()
server_thread.join()
@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()