def __init__(self, observation_space, action_space, config, existing_inputs=None): config = dict(ray.rllib.agents.impala.impala.DEFAULT_CONFIG, **config) assert config["batch_mode"] == "truncate_episodes", \ "Must use `truncate_episodes` batch mode with V-trace." self.config = config self.sess = tf.get_default_session() self.grads = None if isinstance(action_space, gym.spaces.Discrete): is_multidiscrete = False output_hidden_shape = [action_space.n] elif isinstance(action_space, gym.spaces.multi_discrete.MultiDiscrete): is_multidiscrete = True output_hidden_shape = action_space.nvec.astype(np.int32) elif self.config["vtrace"]: raise UnsupportedSpaceException( "Action space {} is not supported for APPO + VTrace.", format(action_space)) else: is_multidiscrete = False output_hidden_shape = 1 # Policy network model dist_class, logit_dim = ModelCatalog.get_action_dist( action_space, self.config["model"]) # Create input placeholders if existing_inputs: if self.config["vtrace"]: actions, dones, behaviour_logits, rewards, observations, \ prev_actions, prev_rewards = existing_inputs[:7] existing_state_in = existing_inputs[7:-1] existing_seq_lens = existing_inputs[-1] else: actions, dones, behaviour_logits, rewards, observations, \ prev_actions, prev_rewards, adv_ph, value_targets = \ existing_inputs[:9] existing_state_in = existing_inputs[9:-1] existing_seq_lens = existing_inputs[-1] else: actions = ModelCatalog.get_action_placeholder(action_space) dones = tf.placeholder(tf.bool, [None], name="dones") rewards = tf.placeholder(tf.float32, [None], name="rewards") behaviour_logits = tf.placeholder(tf.float32, [None, logit_dim], name="behaviour_logits") observations = tf.placeholder(tf.float32, [None] + list(observation_space.shape)) existing_state_in = None existing_seq_lens = None if not self.config["vtrace"]: adv_ph = tf.placeholder(tf.float32, name="advantages", shape=(None, )) value_targets = tf.placeholder(tf.float32, name="value_targets", shape=(None, )) self.observations = observations # Unpack behaviour logits unpacked_behaviour_logits = tf.split(behaviour_logits, output_hidden_shape, axis=1) # Setup the policy dist_class, logit_dim = ModelCatalog.get_action_dist( action_space, self.config["model"]) prev_actions = ModelCatalog.get_action_placeholder(action_space) prev_rewards = tf.placeholder(tf.float32, [None], name="prev_reward") self.model = ModelCatalog.get_model( { "obs": observations, "prev_actions": prev_actions, "prev_rewards": prev_rewards, "is_training": self._get_is_training_placeholder(), }, observation_space, logit_dim, self.config["model"], state_in=existing_state_in, seq_lens=existing_seq_lens) unpacked_outputs = tf.split(self.model.outputs, output_hidden_shape, axis=1) dist_inputs = unpacked_outputs if is_multidiscrete else \ self.model.outputs prev_dist_inputs = unpacked_behaviour_logits if is_multidiscrete else \ behaviour_logits action_dist = dist_class(dist_inputs) prev_action_dist = dist_class(prev_dist_inputs) values = self.model.value_function() self.value_function = values self.var_list = tf.get_collection(tf.GraphKeys.TRAINABLE_VARIABLES, tf.get_variable_scope().name) def make_time_major(tensor, drop_last=False): """Swaps batch and trajectory axis. Args: tensor: A tensor or list of tensors to reshape. drop_last: A bool indicating whether to drop the last trajectory item. Returns: res: A tensor with swapped axes or a list of tensors with swapped axes. """ if isinstance(tensor, list): return [make_time_major(t, drop_last) for t in tensor] if self.model.state_init: B = tf.shape(self.model.seq_lens)[0] T = tf.shape(tensor)[0] // B else: # Important: chop the tensor into batches at known episode cut # boundaries. TODO(ekl) this is kind of a hack T = self.config["sample_batch_size"] B = tf.shape(tensor)[0] // T rs = tf.reshape(tensor, tf.concat([[B, T], tf.shape(tensor)[1:]], axis=0)) # swap B and T axes res = tf.transpose( rs, [1, 0] + list(range(2, 1 + int(tf.shape(tensor).shape[0])))) if drop_last: return res[:-1] return res if self.model.state_in: max_seq_len = tf.reduce_max(self.model.seq_lens) - 1 mask = tf.sequence_mask(self.model.seq_lens, max_seq_len) mask = tf.reshape(mask, [-1]) else: mask = tf.ones_like(rewards) # Inputs are reshaped from [B * T] => [T - 1, B] for V-trace calc. if self.config["vtrace"]: logger.info("Using V-Trace surrogate loss (vtrace=True)") # Prepare actions for loss loss_actions = actions if is_multidiscrete else tf.expand_dims( actions, axis=1) self.loss = VTraceSurrogateLoss( actions=make_time_major(loss_actions, drop_last=True), prev_actions_logp=make_time_major( prev_action_dist.logp(actions), drop_last=True), actions_logp=make_time_major(action_dist.logp(actions), drop_last=True), action_kl=prev_action_dist.kl(action_dist), actions_entropy=make_time_major(action_dist.entropy(), drop_last=True), dones=make_time_major(dones, drop_last=True), behaviour_logits=make_time_major(unpacked_behaviour_logits, drop_last=True), target_logits=make_time_major(unpacked_outputs, drop_last=True), discount=config["gamma"], rewards=make_time_major(rewards, drop_last=True), values=make_time_major(values, drop_last=True), bootstrap_value=make_time_major(values)[-1], valid_mask=make_time_major(mask, drop_last=True), vf_loss_coeff=self.config["vf_loss_coeff"], entropy_coeff=self.config["entropy_coeff"], clip_rho_threshold=self.config["vtrace_clip_rho_threshold"], clip_pg_rho_threshold=self. config["vtrace_clip_pg_rho_threshold"], clip_param=self.config["clip_param"]) else: logger.info("Using PPO surrogate loss (vtrace=False)") self.loss = PPOSurrogateLoss( prev_actions_logp=make_time_major( prev_action_dist.logp(actions)), actions_logp=make_time_major(action_dist.logp(actions)), action_kl=prev_action_dist.kl(action_dist), actions_entropy=make_time_major(action_dist.entropy()), values=make_time_major(values), valid_mask=make_time_major(mask), advantages=make_time_major(adv_ph), value_targets=make_time_major(value_targets), vf_loss_coeff=self.config["vf_loss_coeff"], entropy_coeff=self.config["entropy_coeff"], clip_param=self.config["clip_param"]) # KL divergence between worker and learner logits for debugging model_dist = MultiCategorical(unpacked_outputs) behaviour_dist = MultiCategorical(unpacked_behaviour_logits) kls = model_dist.kl(behaviour_dist) if len(kls) > 1: self.KL_stats = {} for i, kl in enumerate(kls): self.KL_stats.update({ "mean_KL_{}".format(i): tf.reduce_mean(kl), "max_KL_{}".format(i): tf.reduce_max(kl), "median_KL_{}".format(i): tf.contrib.distributions.percentile(kl, 50.0), }) else: self.KL_stats = { "mean_KL": tf.reduce_mean(kls[0]), "max_KL": tf.reduce_max(kls[0]), "median_KL": tf.contrib.distributions.percentile(kls[0], 50.0), } # Initialize TFPolicyGraph loss_in = [ ("actions", actions), ("dones", dones), ("behaviour_logits", behaviour_logits), ("rewards", rewards), ("obs", observations), ("prev_actions", prev_actions), ("prev_rewards", prev_rewards), ] if not self.config["vtrace"]: loss_in.append(("advantages", adv_ph)) loss_in.append(("value_targets", value_targets)) LearningRateSchedule.__init__(self, self.config["lr"], self.config["lr_schedule"]) TFPolicyGraph.__init__( self, observation_space, action_space, self.sess, obs_input=observations, action_sampler=action_dist.sample(), action_prob=action_dist.sampled_action_prob(), loss=self.loss.total_loss, model=self.model, loss_inputs=loss_in, state_inputs=self.model.state_in, state_outputs=self.model.state_out, prev_action_input=prev_actions, prev_reward_input=prev_rewards, seq_lens=self.model.seq_lens, max_seq_len=self.config["model"]["max_seq_len"], batch_divisibility_req=self.config["sample_batch_size"]) self.sess.run(tf.global_variables_initializer()) values_batched = make_time_major(values, drop_last=self.config["vtrace"]) self.stats_fetches = { "stats": dict( { "cur_lr": tf.cast(self.cur_lr, tf.float64), "policy_loss": self.loss.pi_loss, "entropy": self.loss.entropy, "grad_gnorm": tf.global_norm(self._grads), "var_gnorm": tf.global_norm(self.var_list), "vf_loss": self.loss.vf_loss, "vf_explained_var": explained_variance( tf.reshape(self.loss.value_targets, [-1]), tf.reshape(values_batched, [-1])), }, **self.KL_stats), }
def __init__(self, observation_space, action_space, config, existing_inputs=None): config = dict(ray.rllib.agents.impala.impala.DEFAULT_CONFIG, **config) assert config["batch_mode"] == "truncate_episodes", \ "Must use `truncate_episodes` batch mode with V-trace." self.config = config self.sess = tf.get_default_session() self.grads = None if isinstance(action_space, gym.spaces.Discrete): is_multidiscrete = False output_hidden_shape = [action_space.n] elif isinstance(action_space, gym.spaces.multi_discrete.MultiDiscrete): is_multidiscrete = True output_hidden_shape = action_space.nvec.astype(np.int32) elif self.config["vtrace"]: raise UnsupportedSpaceException( "Action space {} is not supported for APPO + VTrace.", format(action_space)) else: is_multidiscrete = False output_hidden_shape = 1 # Policy network model dist_class, logit_dim = ModelCatalog.get_action_dist( action_space, self.config["model"]) # Create input placeholders if existing_inputs: if self.config["vtrace"]: actions, dones, behaviour_logits, rewards, observations, \ prev_actions, prev_rewards = existing_inputs[:7] existing_state_in = existing_inputs[7:-1] existing_seq_lens = existing_inputs[-1] else: actions, dones, behaviour_logits, rewards, observations, \ prev_actions, prev_rewards, adv_ph, value_targets = \ existing_inputs[:9] existing_state_in = existing_inputs[9:-1] existing_seq_lens = existing_inputs[-1] else: actions = ModelCatalog.get_action_placeholder(action_space) dones = tf.placeholder(tf.bool, [None], name="dones") rewards = tf.placeholder(tf.float32, [None], name="rewards") behaviour_logits = tf.placeholder( tf.float32, [None, logit_dim], name="behaviour_logits") observations = tf.placeholder( tf.float32, [None] + list(observation_space.shape)) existing_state_in = None existing_seq_lens = None if not self.config["vtrace"]: adv_ph = tf.placeholder( tf.float32, name="advantages", shape=(None, )) value_targets = tf.placeholder( tf.float32, name="value_targets", shape=(None, )) self.observations = observations # Unpack behaviour logits unpacked_behaviour_logits = tf.split( behaviour_logits, output_hidden_shape, axis=1) # Setup the policy dist_class, logit_dim = ModelCatalog.get_action_dist( action_space, self.config["model"]) prev_actions = ModelCatalog.get_action_placeholder(action_space) prev_rewards = tf.placeholder(tf.float32, [None], name="prev_reward") self.model = ModelCatalog.get_model( { "obs": observations, "prev_actions": prev_actions, "prev_rewards": prev_rewards, "is_training": self._get_is_training_placeholder(), }, observation_space, action_space, logit_dim, self.config["model"], state_in=existing_state_in, seq_lens=existing_seq_lens) unpacked_outputs = tf.split( self.model.outputs, output_hidden_shape, axis=1) dist_inputs = unpacked_outputs if is_multidiscrete else \ self.model.outputs prev_dist_inputs = unpacked_behaviour_logits if is_multidiscrete else \ behaviour_logits action_dist = dist_class(dist_inputs) prev_action_dist = dist_class(prev_dist_inputs) values = self.model.value_function() self.value_function = values self.var_list = tf.get_collection(tf.GraphKeys.TRAINABLE_VARIABLES, tf.get_variable_scope().name) def make_time_major(tensor, drop_last=False): """Swaps batch and trajectory axis. Args: tensor: A tensor or list of tensors to reshape. drop_last: A bool indicating whether to drop the last trajectory item. Returns: res: A tensor with swapped axes or a list of tensors with swapped axes. """ if isinstance(tensor, list): return [make_time_major(t, drop_last) for t in tensor] if self.model.state_init: B = tf.shape(self.model.seq_lens)[0] T = tf.shape(tensor)[0] // B else: # Important: chop the tensor into batches at known episode cut # boundaries. TODO(ekl) this is kind of a hack T = self.config["sample_batch_size"] B = tf.shape(tensor)[0] // T rs = tf.reshape(tensor, tf.concat([[B, T], tf.shape(tensor)[1:]], axis=0)) # swap B and T axes res = tf.transpose( rs, [1, 0] + list(range(2, 1 + int(tf.shape(tensor).shape[0])))) if drop_last: return res[:-1] return res if self.model.state_in: max_seq_len = tf.reduce_max(self.model.seq_lens) - 1 mask = tf.sequence_mask(self.model.seq_lens, max_seq_len) mask = tf.reshape(mask, [-1]) else: mask = tf.ones_like(rewards) # Inputs are reshaped from [B * T] => [T - 1, B] for V-trace calc. if self.config["vtrace"]: logger.info("Using V-Trace surrogate loss (vtrace=True)") # Prepare actions for loss loss_actions = actions if is_multidiscrete else tf.expand_dims( actions, axis=1) self.loss = VTraceSurrogateLoss( actions=make_time_major(loss_actions, drop_last=True), prev_actions_logp=make_time_major( prev_action_dist.logp(actions), drop_last=True), actions_logp=make_time_major( action_dist.logp(actions), drop_last=True), action_kl=prev_action_dist.kl(action_dist), actions_entropy=make_time_major( action_dist.entropy(), drop_last=True), dones=make_time_major(dones, drop_last=True), behaviour_logits=make_time_major( unpacked_behaviour_logits, drop_last=True), target_logits=make_time_major( unpacked_outputs, drop_last=True), discount=config["gamma"], rewards=make_time_major(rewards, drop_last=True), values=make_time_major(values, drop_last=True), bootstrap_value=make_time_major(values)[-1], valid_mask=make_time_major(mask, drop_last=True), vf_loss_coeff=self.config["vf_loss_coeff"], entropy_coeff=self.config["entropy_coeff"], clip_rho_threshold=self.config["vtrace_clip_rho_threshold"], clip_pg_rho_threshold=self.config[ "vtrace_clip_pg_rho_threshold"], clip_param=self.config["clip_param"]) else: logger.info("Using PPO surrogate loss (vtrace=False)") self.loss = PPOSurrogateLoss( prev_actions_logp=make_time_major( prev_action_dist.logp(actions)), actions_logp=make_time_major(action_dist.logp(actions)), action_kl=prev_action_dist.kl(action_dist), actions_entropy=make_time_major(action_dist.entropy()), values=make_time_major(values), valid_mask=make_time_major(mask), advantages=make_time_major(adv_ph), value_targets=make_time_major(value_targets), vf_loss_coeff=self.config["vf_loss_coeff"], entropy_coeff=self.config["entropy_coeff"], clip_param=self.config["clip_param"]) # KL divergence between worker and learner logits for debugging model_dist = MultiCategorical(unpacked_outputs) behaviour_dist = MultiCategorical(unpacked_behaviour_logits) kls = model_dist.kl(behaviour_dist) if len(kls) > 1: self.KL_stats = {} for i, kl in enumerate(kls): self.KL_stats.update({ "mean_KL_{}".format(i): tf.reduce_mean(kl), "max_KL_{}".format(i): tf.reduce_max(kl), "median_KL_{}".format(i): tf.contrib.distributions. percentile(kl, 50.0), }) else: self.KL_stats = { "mean_KL": tf.reduce_mean(kls[0]), "max_KL": tf.reduce_max(kls[0]), "median_KL": tf.contrib.distributions.percentile(kls[0], 50.0), } # Initialize TFPolicyGraph loss_in = [ ("actions", actions), ("dones", dones), ("behaviour_logits", behaviour_logits), ("rewards", rewards), ("obs", observations), ("prev_actions", prev_actions), ("prev_rewards", prev_rewards), ] if not self.config["vtrace"]: loss_in.append(("advantages", adv_ph)) loss_in.append(("value_targets", value_targets)) LearningRateSchedule.__init__(self, self.config["lr"], self.config["lr_schedule"]) TFPolicyGraph.__init__( self, observation_space, action_space, self.sess, obs_input=observations, action_sampler=action_dist.sample(), action_prob=action_dist.sampled_action_prob(), loss=self.loss.total_loss, model=self.model, loss_inputs=loss_in, state_inputs=self.model.state_in, state_outputs=self.model.state_out, prev_action_input=prev_actions, prev_reward_input=prev_rewards, seq_lens=self.model.seq_lens, max_seq_len=self.config["model"]["max_seq_len"], batch_divisibility_req=self.config["sample_batch_size"]) self.sess.run(tf.global_variables_initializer()) values_batched = make_time_major( values, drop_last=self.config["vtrace"]) self.stats_fetches = { "stats": dict({ "cur_lr": tf.cast(self.cur_lr, tf.float64), "policy_loss": self.loss.pi_loss, "entropy": self.loss.entropy, "grad_gnorm": tf.global_norm(self._grads), "var_gnorm": tf.global_norm(self.var_list), "vf_loss": self.loss.vf_loss, "vf_explained_var": explained_variance( tf.reshape(self.loss.value_targets, [-1]), tf.reshape(values_batched, [-1])), }, **self.KL_stats), }