mirror of https://github.com/hpcaitech/ColossalAI
40 lines
1.7 KiB
Python
40 lines
1.7 KiB
Python
import torch
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from coati.models.generation import generate_with_actor
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from coati.models.utils import calc_action_log_probs, compute_reward, normalize
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from .base import Experience, ExperienceMaker
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class NaiveExperienceMaker(ExperienceMaker):
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"""
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Naive experience maker.
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"""
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@torch.no_grad()
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def make_experience(self, input_ids: torch.Tensor, **generate_kwargs) -> Experience:
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self.actor.eval()
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self.critic.eval()
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self.initial_model.eval()
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self.reward_model.eval()
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sequences, attention_mask, action_mask = generate_with_actor(self.actor,
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input_ids,
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return_action_mask=True,
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**generate_kwargs)
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num_actions = action_mask.size(1)
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actor_output = self.actor(sequences, attention_mask)
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action_log_probs = calc_action_log_probs(actor_output, sequences, num_actions)
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base_model_output = self.initial_model(sequences, attention_mask)
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base_action_log_probs = calc_action_log_probs(base_model_output, sequences, num_actions)
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value = self.critic(sequences, action_mask, attention_mask)
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r = self.reward_model(sequences, attention_mask)
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reward = compute_reward(r, self.kl_coef, action_log_probs, base_action_log_probs, action_mask=action_mask)
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advantage = reward - value
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# TODO(ver217): maybe normalize adv
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if advantage.ndim == 1:
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advantage = advantage.unsqueeze(-1)
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return Experience(sequences, action_log_probs, value, reward, advantage, attention_mask, action_mask)
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