Files
ray/python/ray/rllib/agents/ddpg/apex.py
T
Eric LiangandGitHub 9ea57c2a93 [rllib] Basic IMPALA implementation (using deepmind's reference vtrace.py) (#2504)
Rename AsyncSamplesOptimizer -> AsyncReplayOptimizer
  Add AsyncSamplesOptimizer that implements the IMPALA architecture
  integrate V-trace with a3c policy graph
  audit V-trace integration
  benchmark compare vs A3C and with V-trace on/off
PongNoFrameskip-v4 on IMPALA scaling from 16 to 128 workers, solving Pong in <10 min. For reference, solving this env takes ~40 minutes for Ape-X and several hours for A3C.
2018-08-01 20:53:53 -07:00

62 lines
2.1 KiB
Python

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
from ray.rllib.agents.ddpg.ddpg import DDPGAgent, DEFAULT_CONFIG as DDPG_CONFIG
from ray.rllib.utils import merge_dicts
from ray.tune.trial import Resources
APEX_DDPG_DEFAULT_CONFIG = merge_dicts(
DDPG_CONFIG,
{
"optimizer_class": "AsyncReplayOptimizer",
"optimizer": merge_dicts(
DDPG_CONFIG["optimizer"], {
"max_weight_sync_delay": 400,
"num_replay_buffer_shards": 4,
"debug": False
}),
"n_step": 3,
"gpu": False,
"num_workers": 32,
"buffer_size": 2000000,
"learning_starts": 50000,
"train_batch_size": 512,
"sample_batch_size": 50,
"max_weight_sync_delay": 400,
"target_network_update_freq": 500000,
"timesteps_per_iteration": 25000,
"per_worker_exploration": True,
"worker_side_prioritization": True,
"min_iter_time_s": 30,
},
)
class ApexDDPGAgent(DDPGAgent):
"""DDPG variant that uses the Ape-X distributed policy optimizer.
By default, this is configured for a large single node (32 cores). For
running in a large cluster, increase the `num_workers` config var.
"""
_agent_name = "APEX_DDPG"
_default_config = APEX_DDPG_DEFAULT_CONFIG
@classmethod
def default_resource_request(cls, config):
cf = merge_dicts(cls._default_config, config)
return Resources(
cpu=1 + cf["optimizer"]["num_replay_buffer_shards"],
gpu=cf["gpu"] and 1 or 0,
extra_cpu=cf["num_cpus_per_worker"] * cf["num_workers"],
extra_gpu=cf["num_gpus_per_worker"] * cf["num_workers"])
def update_target_if_needed(self):
# Ape-X updates based on num steps trained, not sampled
if self.optimizer.num_steps_trained - self.last_target_update_ts > \
self.config["target_network_update_freq"]:
self.local_evaluator.for_policy(lambda p: p.update_target())
self.last_target_update_ts = self.optimizer.num_steps_trained
self.num_target_updates += 1