modelscope--ms-swift
wehub-resource-sync
676 行
36 KiB
Python
676 行
36 KiB
Python
# Copyright (c) ModelScope Contributors. All rights reserved.
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import os
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from dataclasses import dataclass, field
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from typing import Any, Dict, List, Literal, Optional
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from swift.model import MODEL_MAPPING
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from swift.rlhf_trainers import GRPOArgumentsMixin
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from swift.template import TEMPLATE_MAPPING
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from swift.utils import get_current_device, get_logger, is_master, is_mp, json_parse_to_dict, set_default_ddp_config
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from .sft_args import SftArguments
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logger = get_logger()
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rlhf_support_vllm_types = ['grpo', 'gkd']
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@dataclass
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class RewardModelArguments:
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"""Arguments pertaining to the reward model.
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Args:
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reward_model (Optional[List[str]]): The model ID or a local path to the reward model. Same as the `model`
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argument. Defaults to None.
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reward_adapters (List[str]): The path(s) to LoRA adapter weights to be loaded for the reward model. Useful for
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using LoRA weights from SFT as the reward model. Defaults to an empty list (`[]`).
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reward_model_type (Optional[List[str]]): The model type of the reward model. Same as the `model_type` argument.
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If not specified, it's often inferred. Defaults to None.
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reward_model_revision (Optional[List[str]]): The specific model version to use for the reward model. Same as
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the `model_revision` argument. Defaults to None.
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reward_template (Optional[List[str]]): The template to use for the reward model. Defaults to None.
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"""
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reward_model: Optional[List[str]] = None
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reward_adapters: List[str] = field(default_factory=list)
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reward_model_type: Optional[List[str]] = field(
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default=None, metadata={'help': f'model_type choices: {list(MODEL_MAPPING.keys())}'})
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reward_model_revision: Optional[List[str]] = None
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reward_template: Optional[List[str]] = field(
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default=None, metadata={'help': f'template choices: {list(TEMPLATE_MAPPING.keys())}'})
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@dataclass
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class TeacherModelArguments:
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"""Arguments for configuring the teacher model.
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Args:
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teacher_model (Optional[str]): The model ID or a local path to the teacher model. Analogous to the main
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`model` argument. For GKD, there are three modes:
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- Not set (None): Self-distillation with dynamic teacher (teacher = current student weights).
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- Same as `model` with LoRA training: Self-distillation with fixed teacher. Automatically optimized
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to use `disable_adapter()` to get base model logits without loading an extra model.
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- Different from `model`: Standard GKD with an independent frozen teacher model.
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Defaults to None.
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teacher_adapters (List[str]): A list of paths to LoRA weights. These weights, often produced by SFT, are loaded
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to form the teacher model. Defaults to an empty list (`[]`).
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teacher_model_type (Optional[str]): The model type of the teacher model. If not specified, it's often inferred.
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Analogous to the main `model_type` argument. Defaults to None.
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teacher_model_revision (Optional[str]): The specific model version of the teacher model to use. Analogous to
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the main `model_revision` argument. Defaults to None.
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teacher_deepspeed (Optional[str]): The teacher model's deepspeed configuration. This can be a JSON file path or
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one of the following values: 'zero0', 'zero1', 'zero2', 'zero3', 'zero2_offload', 'zero3_offload'. If not
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provided, it defaults to using the same DeepSpeed configuration as the main training model. Analogous to
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the main `deepspeed` argument.
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teacher_model_server (Optional[str]): The URL of the teacher model server (e.g., 'http://localhost:8000').
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When set, the teacher logprobs will be fetched from the external API service (e.g., swift deploy, vLLM)
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instead of loading a local teacher model. This enables using larger teacher models or services hosted
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remotely. When this is set, `teacher_model` is not required. Defaults to None.
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offload_teacher_model (bool): Whether to offload the teacher model to CPU memory to save VRAM during GKD
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or OPD-RL training. When enabled, the teacher model is loaded to GPU only during forward pass and
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offloaded back to CPU afterwards. Defaults to False.
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"""
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teacher_model: Optional[str] = None
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teacher_adapters: List[str] = field(default_factory=list)
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teacher_model_type: Optional[str] = field(
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default=None, metadata={'help': f'model_type choices: {list(MODEL_MAPPING.keys())}'})
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teacher_model_revision: Optional[str] = None
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teacher_deepspeed: Optional[str] = field(
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default=None,
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metadata={
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'help':
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'DeepSpeed configuration for teacher model. '
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'Can be a path to a json file or one of: zero0, zero1, zero2, zero3, zero2_offload, zero3_offload'
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})
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teacher_model_server: Optional[str] = field(
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default=None,
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metadata={
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'help':
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'URL of the teacher model server (e.g., http://localhost:8000). '
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'When set, teacher logprobs are fetched via API instead of loading a local model. '
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'Supports multi-teacher via JSON list of {url, tags}.'
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})
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offload_teacher_model: bool = False
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@dataclass
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class PPOArguments:
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"""Arguments for configuring the PPO training.
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Args:
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num_ppo_epochs (int): Number of epochs to train. Defaults to 4.
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whiten_rewards (bool): Whether to whiten the rewards. Defaults to False.
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kl_coef (float): KL coefficient. Defaults to 0.05.
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cliprange (float): Clip range. Defaults to 0.2.
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vf_coef (float): Value function coefficient. Defaults to 0.1.
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cliprange_value (float): Clip range for the value function. Defaults to 0.2.
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gamma (float): Discount factor. Defaults to 1.0.
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lam (float): Lambda value for GAE. Defaults to 0.95.
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num_mini_batches (int): Defaults to 1.
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local_rollout_forward_batch_size (int): Defaults to 64.
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num_sample_generations (int): Number of generations. Defaults to 10.
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response_length (Optional[int]): (Deprecated) Compatibility parameter. Use `max_completion_length` instead.
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Defaults to None.
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missing_eos_penalty (Optional[float]): Defaults to None.
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"""
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num_ppo_epochs: int = 4
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whiten_rewards: bool = False
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kl_coef: float = 0.05
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cliprange: float = 0.2
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vf_coef: float = 0.1
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cliprange_value: float = 0.2
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gamma: float = 1.0
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lam: float = 0.95
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num_mini_batches: int = 1
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local_rollout_forward_batch_size: int = 64
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num_sample_generations: int = 10
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response_length: Optional[int] = None # compat. use max_completion_length instead
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missing_eos_penalty: Optional[float] = None
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@dataclass
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class GRPOArguments(GRPOArgumentsMixin):
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"""A dataclass for configuring GRPO training.
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These arguments control the hyperparameters specific to the GRPO algorithm.
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Args:
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num_generations (int): The number of completions to generate for each prompt. This corresponds to the G value
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in the GRPO paper. The total generation batch size (e.g., `generation_batch_size` or `steps_per_generation
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* per_device_batch_size * num_processes`) must be divisible by this number. Defaults to 8.
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num_generations_eval (Optional[int]): Number of generations to sample during evaluation. This allows
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using fewer generations during evaluation to save computation. If `None`, uses the value of
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`num_generations`. Defaults to None.
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reward_funcs (List[str]): A list of reward function names to use for the GRPO algorithm. Available built-in
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options include 'accuracy', 'format', 'cosine', 'repetition', and 'soft_overlong'
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(see swift/rewards/orm.py). Custom reward functions can also be defined. Defaults to an empty list.
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reward_weights (List[float]): A list of weights for each reward source. The length must match the total number
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of reward functions (from `reward_funcs`) plus any external reward models. If `None`, all rewards are
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weighted equally with a value of 1.0. Note: If an external `--reward_model` is used, it is treated as the
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last reward source in the sequence. Defaults to None.
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log_completions (bool): Whether to log the model's generated completions during training. This is designed to
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be used with an experiment tracker like WandB or SwanLab (`--report_to wandb`/`swanlab`). If enabled
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without a tracker, completions are saved to `completions.jsonl` in the checkpoint directory. Defaults to
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False.
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num_iterations (int): The number of update steps to perform for each data sample. This corresponds to the K
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value in the GRPO paper. Defaults to 1.
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truncation_strategy (Literal['delete', 'left', 'right', 'split', None]): The strategy for handling input
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sequences that exceed `max_length`. Supported options: 'delete' to discard the sample, 'left' to truncate
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from the beginning, 'right' to truncate from the end. Defaults to None, and then sets to 'left' in the
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`_init_grpo` function.
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Note that for multimodal models, left pruning may prune multimodal tokens, causing shape mismatch errors
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in the forward feed. Using the `delete` method will resample other data from the original dataset to
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supplement excessively long data and examples with encoding failures.
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"""
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num_generations: int = 8 # G in the GRPO paper
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reward_funcs: List[str] = field(default_factory=list)
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reward_weights: List[float] = None
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log_completions: bool = False
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# multi step
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num_iterations: int = 1
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truncation_strategy: Literal['delete', 'left', 'right', 'split', None] = None
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@dataclass
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class RLHFArguments(TeacherModelArguments, GRPOArguments, PPOArguments, RewardModelArguments, SftArguments):
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"""A dataclass holding arguments for Reinforcement Learning from Human Feedback.
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Args:
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rlhf_type (str): The type of human alignment algorithm to use. Supports 'dpo', 'orpo', 'simpo', 'kto', 'cpo',
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'rm', 'ppo', 'grpo', and 'gkd'. Defaults to 'dpo'.
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ref_model (Optional[str]): The model path for the reference model. Required when using 'dpo', 'kto', 'ppo',
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or 'grpo' with full-parameter training. Defaults to None, which will set it to the value of the `--model`
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argument.
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ref_adapters (List[str]): LoRA adapters for the reference model. If you are using LoRA weights from SFT for
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DPO/KTO/GRPO, set both `--adapters` and `--ref_adapters` to the SFT checkpoint path. When resuming from an
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RLHF checkpoint, set `--resume_from_checkpoint` to the RLHF checkpoint and `--ref_adapters` to the SFT
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checkpoint. Defaults to an empty list.
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ref_model_type (Optional[str]): The model type of the reference model. Same as `model_type`. Defaults to None.
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ref_model_revision (Optional[str]): The model revision of the reference model. Same as `model_revision`.
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Defaults to None.
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beta (Optional[float]): The beta parameter for RLHF, controlling the deviation from the reference model.
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A higher value implies less deviation. If None, uses algorithm-specific defaults: 2.0 for 'simpo', 0.04
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for 'grpo', 0.5 for 'gkd', and 0.1 for others. Defaults to None.
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label_smoothing (float): The label smoothing value for DPO. A value of 0 disables it. Defaults to 0.
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max_completion_length (int): The maximum generation length for GRPO/PPO/GKD algorithms. Defaults to 512.
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loss_scale (Optional[str]): Overrides the template parameter. During RLHF training, this defaults to
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'last_round'.
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rpo_alpha (Optional[float]): The alpha parameter from the RPO paper, controlling the weight of the SFT loss
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(NLL term). The loss is calculated as `dpo_loss + rpo_alpha * sft_loss`. If None, the SFT loss is not
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included.
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ld_alpha (Optional[float]): The alpha parameter from the LD-DPO paper, which weights the log probabilities of
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the sequence part beyond the common prefix to mitigate length preference. Defaults to None.
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discopop_tau (float): The temperature parameter from the DiscoPOP paper, used to scale the log-ratio. Effective
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when `loss_type` is 'discopop'. Defaults to 0.05.
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loss_type (Optional[List[str]]): The type of loss function. Defaults to algorithm-specific values (e.g.,
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'sigmoid' for DPO). Multiple values can be passed for mixed training (MPO), which requires `loss_weights`
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to be set.
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loss_weights (Optional[List[float]]): When multiple `loss_type` values are set for DPO, this specifies the
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weights for each loss term. Defaults to None.
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cpo_alpha (float): The coefficient for the NLL loss in the CPO/SimPO loss function. Defaults to 1.0.
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simpo_gamma (float): The reward margin term in the SimPO algorithm. The paper suggests a value between 0.5 and
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1.5. Defaults to 1.0.
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desirable_weight (float): In KTO, the weight applied to the desirable loss to counteract data imbalance.
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Defaults to 1.0.
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undesirable_weight (float): In KTO, the weight applied to the undesirable loss to counteract data imbalance.
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Defaults to 1.0.
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temperature (float): The temperature for sampling, used in PPO, GRPO, and GKD algorithms. Defaults to 0.9.
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center_rewards_coefficient (Optional[float]): Used for Reward Model (RM) training. A coefficient to encourage
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the reward model to output rewards with a mean of zero. A value of 0.01 is recommended. Defaults to None.
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sft_alpha (float): The weight for the SFT loss component in GKD. The final loss is calculated as
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gkd_loss + sft_alpha * sft_loss`. Defaults to 0.
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lmbda (float): The lambda parameter for GKD, balancing policy and value losses. Defaults to 0.5.
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seq_kd (bool): Deprecated. Sequential KD (teacher-generated responses) is not implemented.
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gkd_logits_topk (Optional[int]): The number of top-k logits to use for KL divergence computation in GKD.
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If None, uses full vocabulary for KL computation (more accurate but memory-intensive).
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If set to a positive integer, only top-k teacher logits are used (more efficient).
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When using `teacher_model_server`, this is limited by the server's `max_logprobs` setting
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(vLLM default is 20, can be increased with `--max-logprobs`). Defaults to None.
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max_new_tokens (Optional[int]): A backward-compatibility argument. Please use `max_completion_length` instead.
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Defaults to None.
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"""
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rlhf_type: Literal['dpo', 'orpo', 'simpo', 'kto', 'cpo', 'rm', 'ppo', 'grpo', 'gkd'] = 'dpo'
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ref_model: Optional[str] = None
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ref_adapters: List[str] = field(default_factory=list)
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ref_model_type: Optional[str] = field(
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default=None, metadata={'help': f'model_type choices: {list(MODEL_MAPPING.keys())}'})
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ref_model_revision: Optional[str] = None
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beta: Optional[float] = None
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label_smoothing: float = 0
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max_completion_length: int = 512
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loss_scale: Optional[str] = None # 'last_round'
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# DPO
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rpo_alpha: Optional[float] = None
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ld_alpha: Optional[float] = None # α parameter from the LD-DPO paper
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discopop_tau: float = 0.05 # τ/temperature parameter from the DiscoPOP paper
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loss_type: Optional[List[str]] = None
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loss_weights: Optional[List[float]] = None
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# CPO
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cpo_alpha: float = 1.
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# SimPO
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simpo_gamma: float = 1
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# KTO
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desirable_weight: float = 1.0
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undesirable_weight: float = 1.0
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# PPO/GRPO/GKD
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temperature: float = 0.9
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# RM
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center_rewards_coefficient: Optional[float] = None
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# GKD
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sft_alpha: float = 0
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lmbda: float = 0.5
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seq_kd: bool = False # Deprecated
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gkd_logits_topk: Optional[int] = None
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# compat
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max_new_tokens: Optional[int] = None # use max_completion_length instead
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def _prepare_training_args(self, training_args: Dict[str, Any]) -> None:
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if self.rlhf_type == 'ppo':
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training_args['world_size'] = self.global_world_size
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def __post_init__(self):
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self._process_loss_type()
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self._init_grpo()
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self._init_rm()
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self._init_simpo()
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self._init_max_completion_length()
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self._init_padding_side()
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self._set_default()
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self._init_rollout()
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self._init_teacher_deepspeed()
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GRPOArguments.__post_init__(self)
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SftArguments.__post_init__(self)
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self._check_sequence_parallel()
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self._check_teacher()
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self._check_grpo()
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self._check_gkd()
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if isinstance(self.ref_adapters, str):
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self.ref_adapters = [self.ref_adapters]
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if self.rlhf_type == 'grpo' and self.beta == 0.0:
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self.ref_model = None
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elif self.rlhf_type in ['dpo', 'kto', 'ppo', 'grpo'] and self.tuner_type == 'full':
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self.ref_model = self.ref_model or self.model
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self.ref_model_type = self.ref_model_type or self.model_type
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self.ref_model_revision = self.ref_model_revision or self.model_revision
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elif self.ref_model is not None:
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raise ValueError('CPO/ORPO or LoRA training does not require a ref_model to be passed in.')
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def _set_loss_scale(self):
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if self.loss_scale is None:
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if self.rlhf_type == 'orpo' and not self.model_meta.is_multimodal:
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# Avoid padding labels during the model's forward pass in multimodal models.
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# Some multimodal models do not expand the image pad token.
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self.loss_scale = 'default'
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elif self.rlhf_type in ('grpo', 'gkd'):
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if self.multi_turn_scheduler:
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self.loss_scale = 'default'
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else:
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self.loss_scale = 'last_round'
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else:
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self.loss_scale = 'last_round'
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super()._set_loss_scale()
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def _process_loss_type(self):
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if self.loss_type is None:
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return
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if isinstance(self.loss_type, list):
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num_loss_types = len(self.loss_type)
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if num_loss_types > 1:
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assert self.rlhf_type == 'dpo', (f'Multiple loss types ({self.loss_type}) are only supported for DPO. '
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f'Current rlhf_type: {self.rlhf_type}.')
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from trl.trainer.dpo_config import DPOConfig
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assert 'loss_weights' in DPOConfig.__dict__, (
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'Multiple loss types requires trl >= 0.20, please install trl `pip install -U trl`')
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if hasattr(self.loss_type, '__len__') and len(self.loss_type) == 1:
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self.loss_type = self.loss_type[0]
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# Validate loss_type
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if self.loss_weights is not None:
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assert self.rlhf_type == 'dpo'
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loss_types = self.loss_type if isinstance(self.loss_type, list) else [self.loss_type]
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if len(self.loss_weights) != len(loss_types):
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raise ValueError(f'Length of loss_weights list ({self.loss_weights}) must match number of loss types '
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f'({loss_types}).')
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def _init_grpo(self):
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if self.rlhf_type != 'grpo':
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return
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if self.cached_dataset or self.cached_val_dataset:
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raise ValueError('cached_dataset is not supported for GRPO.')
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if self.use_vllm:
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set_default_ddp_config()
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if self.async_generate or not self.use_vllm or self.vllm_mode == 'server':
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self.sleep_level = 0
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self.remove_unused_columns = False
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logger.info(f'Setting args.remove_unused_columns: {self.remove_unused_columns}')
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if self.truncation_strategy is None:
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self.truncation_strategy = 'left'
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if self.truncation_strategy not in {'left', 'delete'}:
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raise ValueError("GRPO requires `truncation_strategy 'left' or 'delete'`, "
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f"Current value: `truncation_strategy='{self.truncation_strategy}'`.")
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if self.beta is None:
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self.beta = 0.04 # https://arxiv.org/abs/2402.03300
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if self.async_generate:
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logger.info('Using async mode. This is a approximate version which '
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'will use the old weights to generate responses to accelerate. '
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'This will ignore the `CLIP` of advantages, if you found the training '
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'is unstable, you may consider using --async_generate false.')
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if 'soft_overlong' in self.reward_funcs:
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assert self.soft_cache_length is not None, \
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'The soft_cache_length must be set when using soft overlong rewards.'
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if self.soft_max_length is None:
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self.soft_max_length = self.max_completion_length
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logger.info(f'Auto-configured soft_max_length = max_completion_length {self.max_completion_length}')
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if self.kl_in_reward is None:
|
||
if self.advantage_estimator == 'grpo':
|
||
self.kl_in_reward = False
|
||
elif self.advantage_estimator in ['rloo', 'reinforce_plus_plus']:
|
||
self.kl_in_reward = True
|
||
else:
|
||
raise ValueError(f'Invalid advantage_estimator: {self.advantage_estimator}')
|
||
|
||
# disable normalization, REAL https://arxiv.org/abs/2602.05630
|
||
if self.loss_type == 'real':
|
||
self.scale_rewards = 'none'
|
||
logger.warning(
|
||
f"[REAL] scale_rewards='{self.scale_rewards}' is ignored. "
|
||
"It will be forced to 'none' because 'loss_type = real' does not support reward normalization.")
|
||
|
||
if self.scale_rewards is None:
|
||
if self.advantage_estimator == 'grpo':
|
||
self.scale_rewards = 'group'
|
||
elif self.advantage_estimator == 'rloo':
|
||
self.scale_rewards = 'none'
|
||
elif self.advantage_estimator == 'reinforce_plus_plus':
|
||
self.scale_rewards = 'batch'
|
||
else:
|
||
raise ValueError(f'Invalid advantage_estimator: {self.advantage_estimator}')
|
||
|
||
def _check_teacher(self):
|
||
self._teacher_use_disable_adapter = False
|
||
|
||
if self.rlhf_type not in ['grpo', 'gkd']:
|
||
if self.teacher_model is not None or self.teacher_model_server is not None:
|
||
logger.warning(f'teacher_model / teacher_model_server is ignored for rlhf_type={self.rlhf_type!r} '
|
||
'(only used by gkd and grpo/OPD-RL).')
|
||
return
|
||
teacher_set = self.teacher_model is not None or self.teacher_model_server is not None
|
||
if not teacher_set:
|
||
if self.rlhf_type == 'gkd':
|
||
logger.info('No teacher_model specified. Using self-distillation mode (teacher = student).')
|
||
if self.use_liger_kernel:
|
||
raise ValueError('Self-distillation mode with liger kernel loss is not supported yet')
|
||
if self.rlhf_type == 'grpo' and self.num_generations == 1:
|
||
raise ValueError('num_generations must be greater than 1 for GRPO')
|
||
return
|
||
|
||
if self.rlhf_type == 'grpo' and self.use_liger_kernel:
|
||
raise ValueError('OPD-RL is not supported with use_liger_kernel.')
|
||
|
||
if self.teacher_model is not None and self.teacher_model_server is not None:
|
||
raise ValueError('setting both `teacher_model` and `teacher_model_server` is not supported.')
|
||
|
||
# Validate teacher_model_server: accept single URL or JSON multi-teacher config.
|
||
if self.teacher_model_server is not None:
|
||
from swift.rlhf_trainers.gkd_helpers import parse_teacher_model_server
|
||
|
||
# Parse early to fail fast on invalid JSON; result is re-parsed by the trainer.
|
||
parse_teacher_model_server(self.teacher_model_server)
|
||
|
||
# Self-distillation: teacher_model == student model
|
||
if self.teacher_model is not None and self.teacher_model == self.model:
|
||
if self.tuner_type == 'lora':
|
||
logger.info('LoRA + same teacher_model: using disable_adapter() for fixed teacher (no extra model).')
|
||
self._teacher_use_disable_adapter = True
|
||
self.teacher_model = None
|
||
else:
|
||
# Full training + same teacher_model: a separate frozen copy will be loaded as fixed teacher.
|
||
pass
|
||
|
||
def _init_rollout(self):
|
||
if self.rlhf_type not in rlhf_support_vllm_types:
|
||
return
|
||
|
||
if self.use_vllm and os.getenv('SWIFT_AUDIO_LOAD_BACKEND') is None:
|
||
# align with vLLM audio load backend
|
||
os.environ['SWIFT_AUDIO_LOAD_BACKEND'] = 'soundfile_pyav'
|
||
|
||
if self.vllm_mode is not None and not self.use_vllm:
|
||
raise ValueError('vllm_mode is not supported when use_vllm is false')
|
||
|
||
if self.vllm_mode is None and self.use_vllm:
|
||
raise ValueError('vllm_mode is required when use_vllm is true')
|
||
|
||
self._init_external_vllm()
|
||
|
||
if self.vllm_mode == 'server':
|
||
assert not self.use_vllm or self.vllm_server_host is not None or self.vllm_server_base_url is not None
|
||
|
||
if self.async_generate:
|
||
assert self.vllm_mode == 'server', 'async generate require vllm_mode == server, '
|
||
'please deploy vLLM server by `swift rollout` and assign with `vllm_server_host` '
|
||
'for more infomations, please check '
|
||
'https://swift.readthedocs.io/en/latest/Instruction/GRPO/getstarted/GRPO.html'
|
||
|
||
if not self.use_vllm and self.vllm_tensor_parallel_size != 1:
|
||
self.vllm_tensor_parallel_size = 1
|
||
logger.warning('set vllm_tensor_parallel_size to 1 since use_vllm false')
|
||
self._external_vllm_warning()
|
||
|
||
def _init_padding_side(self):
|
||
if self.rlhf_type in {'ppo', 'gkd'}:
|
||
self.padding_side = 'left'
|
||
# TODO: streaming, MLLM
|
||
|
||
def _init_max_completion_length(self):
|
||
max_completion_length = self.response_length or self.max_new_tokens or self.max_completion_length
|
||
self.max_completion_length = self.max_new_tokens = self.response_length = max_completion_length
|
||
|
||
def _init_metric_for_best_model(self):
|
||
if self.rlhf_type == 'grpo' and self.metric_for_best_model is None:
|
||
self.metric_for_best_model = 'reward'
|
||
super()._init_metric_for_best_model()
|
||
if self.rlhf_type == 'ppo':
|
||
self.metric_for_best_model = None
|
||
self.greater_is_better = None
|
||
|
||
def _init_simpo(self):
|
||
if self.rlhf_type != 'simpo':
|
||
return
|
||
|
||
self.rlhf_type = 'cpo'
|
||
if self.loss_type is None:
|
||
self.loss_type = 'simpo'
|
||
if self.beta is None:
|
||
self.beta = 2.
|
||
|
||
def _init_rm(self):
|
||
if self.rlhf_type == 'rm':
|
||
self.task_type = 'seq_cls'
|
||
self.num_labels = 1
|
||
|
||
def _init_external_vllm(self):
|
||
if self.rlhf_type not in rlhf_support_vllm_types or (self.vllm_server_host is None
|
||
and self.vllm_server_base_url is None):
|
||
return
|
||
from swift.rlhf_trainers import VLLMClient
|
||
if is_master():
|
||
logger.info('Start connecting to vLLM server')
|
||
self.vllm_client = VLLMClient(
|
||
base_urls=self.vllm_server_base_url,
|
||
hosts=self.vllm_server_host,
|
||
server_ports=self.vllm_server_port,
|
||
group_ports=self.vllm_server_group_port,
|
||
connection_timeout=self.vllm_server_timeout)
|
||
self.vllm_client.close_communicator()
|
||
self.vllm_client.init_communicator(device=get_current_device())
|
||
logger.info('Connected to vLLM server')
|
||
|
||
def _set_default(self):
|
||
if self.beta is None:
|
||
if self.rlhf_type == 'gkd':
|
||
self.beta = 0.5
|
||
else:
|
||
self.beta = 0.1
|
||
if self.loss_type is None:
|
||
if self.rlhf_type in ['dpo', 'cpo']:
|
||
self.loss_type = 'sigmoid' # else None
|
||
elif self.rlhf_type in ['kto']:
|
||
self.loss_type = 'kto'
|
||
elif self.rlhf_type == 'grpo':
|
||
self.loss_type = 'grpo'
|
||
if self.gradient_accumulation_steps is None:
|
||
if self.rlhf_type == 'grpo':
|
||
self.gradient_accumulation_steps = 1
|
||
logger.info('Setting default gradient_accumulation_steps to 1 for GRPO.')
|
||
|
||
def _check_grpo(self):
|
||
if self.rlhf_type != 'grpo':
|
||
return
|
||
import importlib.metadata
|
||
import trl
|
||
from packaging import version
|
||
trl_version = version.parse(trl.__version__)
|
||
assert trl_version >= version.parse('0.20'), ('Your current version of `trl` is outdated. '
|
||
'Please update it by running: pip install -U trl')
|
||
if is_mp() and self.use_vllm:
|
||
raise ValueError('GRPO with vLLM is not compatible with `device_map`. '
|
||
'Please set NPROC_PER_NODE equal to num_processes.')
|
||
if self.use_liger_kernel:
|
||
liger_kernel_version = version.parse(importlib.metadata.version('liger-kernel'))
|
||
if liger_kernel_version < version.parse('0.7.0'):
|
||
raise ValueError('Please update liger-kernel to 0.7.0 or later: pip install -U liger-kernel')
|
||
if self.delta is not None:
|
||
raise ValueError('Liger loss does not support two-sided GRPO loss yet.')
|
||
if self.sequence_parallel_size > 1:
|
||
raise ValueError('Liger loss does not support sequence parallel yet.')
|
||
if self.padding_free:
|
||
raise ValueError('Liger loss does not support padding free yet.')
|
||
if self.top_entropy_quantile < 1.0:
|
||
raise ValueError('Liger loss does not support entropy mask yet.')
|
||
if self.log_entropy:
|
||
raise ValueError('Liger loss does not support log entropy yet.')
|
||
if self.off_policy_sequence_mask_delta is not None:
|
||
raise ValueError('Liger loss does not support off-policy sequence masking yet.')
|
||
assert self.importance_sampling_level in [
|
||
'token', 'sequence'
|
||
], ('Liger loss currently only support token-level and sequence-level importance sampling. '
|
||
'Please set `importance_sampling_level` to `token` or `sequence`.')
|
||
if self.advantage_estimator != 'grpo':
|
||
raise ValueError('Liger loss currently only support grpo advantage estimator')
|
||
|
||
if self.async_generate and self.multi_turn_scheduler is not None:
|
||
raise NotImplementedError('Currently, async_generate is not supported with multi-turn functionality.')
|
||
|
||
self._check_opd_rl()
|
||
|
||
def _check_opd_rl(self):
|
||
"""Fail-fast OPD-RL (teacher distillation on GRPO) parameter compatibility.
|
||
|
||
A teacher turns GRPO into OPD-RL, where the teacher signal is a *per-token* advantage
|
||
(the signed teacher log-ratio). Features that require a *per-sequence* advantage (typically
|
||
sign-based judgments) or reward variance are incompatible; reject them here rather than
|
||
deep inside the loss / advantage code. ``_check_teacher`` has already run, so
|
||
``_teacher_use_disable_adapter`` is resolved.
|
||
"""
|
||
opd_rl = (
|
||
self.teacher_model is not None or self.teacher_model_server is not None
|
||
or self._teacher_use_disable_adapter)
|
||
if not opd_rl:
|
||
return
|
||
# loss types / masks that reduce the advantage to a per-sequence scalar (sign-based).
|
||
if self.loss_type in ['real', 'fipo']:
|
||
raise ValueError(f'OPD-RL (teacher) does not support loss_type={self.loss_type!r} '
|
||
'(it needs a per-sequence advantage).')
|
||
if self.off_policy_sequence_mask_delta is not None:
|
||
raise ValueError('OPD-RL (teacher) does not support off_policy_sequence_mask_delta '
|
||
'(it needs a per-sequence advantage).')
|
||
# Pure distillation (no reward functions): the base GRPO advantage is 0, so reward-variance
|
||
# driven features have no signal to act on.
|
||
if not self.reward_funcs:
|
||
if self.dynamic_sample:
|
||
raise ValueError('dynamic_sample requires reward_funcs (it filters groups by reward std); '
|
||
'pure OPD-RL distillation has no reward variance.')
|
||
if self.scale_rewards == 'gdpo':
|
||
raise ValueError("scale_rewards='gdpo' requires reward_funcs; pure OPD-RL distillation has none.")
|
||
|
||
def _external_vllm_warning(self):
|
||
if self.rlhf_type not in rlhf_support_vllm_types or not self.vllm_server_host:
|
||
return
|
||
|
||
if self.vllm_max_model_len is not None:
|
||
logger.warning(
|
||
"Configuration conflict: 'vllm_max_model_len=%s' is ignored for external vLLM. "
|
||
'Please specify it when launching the inference service: '
|
||
'`swift rollout --vllm_max_model_len <value>`', self.vllm_max_model_len)
|
||
|
||
def _check_padding_free(self):
|
||
super()._check_padding_free()
|
||
if self.padding_free or self.packing:
|
||
supported_types = ['grpo', 'dpo', 'kto', 'gkd']
|
||
if self.rlhf_type not in supported_types:
|
||
raise NotImplementedError(
|
||
f"The current rlhf_type '{self.rlhf_type}' does not support padding_free/packing. "
|
||
'Please set --padding_free/packing to false.')
|
||
|
||
def _check_sequence_parallel(self):
|
||
if self.sequence_parallel_size > 1:
|
||
supported_types = ['grpo', 'dpo']
|
||
if self.rlhf_type not in supported_types:
|
||
raise NotImplementedError(
|
||
f"The current rlhf_type '{self.rlhf_type}' does not support sequence_parallel. "
|
||
'Please set --sequence_parallel_size to 1.')
|
||
|
||
def _init_teacher_deepspeed(self):
|
||
"""Initialize teacher_deepspeed configuration similar to _init_deepspeed in SftArguments"""
|
||
if not self.teacher_deepspeed:
|
||
return
|
||
|
||
# Get the same ds_config_folder as main model
|
||
ds_config_folder = os.path.abspath(os.path.join(os.path.dirname(__file__), '..', 'config'))
|
||
deepspeed_mapping = {
|
||
name: f'{name}.json'
|
||
for name in ['zero0', 'zero1', 'zero2', 'zero3', 'zero2_offload', 'zero3_offload']
|
||
}
|
||
|
||
# Check if teacher_deepspeed is a predefined name
|
||
for ds_name, ds_config in deepspeed_mapping.items():
|
||
if self.teacher_deepspeed == ds_name:
|
||
self.teacher_deepspeed = os.path.join(ds_config_folder, ds_config)
|
||
break
|
||
|
||
# Parse the config file to dict
|
||
self.teacher_deepspeed = json_parse_to_dict(self.teacher_deepspeed)
|
||
logger.info(f'Using teacher_deepspeed config: {self.teacher_deepspeed}')
|
||
|
||
def _check_gkd(self):
|
||
if self.rlhf_type != 'gkd':
|
||
return
|
||
if is_mp() and self.use_vllm:
|
||
raise ValueError('GKD with vLLM is not compatible with `device_map`. '
|
||
'Please set NPROC_PER_NODE equal to num_processes.')
|
||
|
||
if self.async_generate:
|
||
raise NotImplementedError('Currently, async_generate is not supported for GKD.')
|
||
|
||
# seq_kd (teacher-generated responses) is not implemented; raise early.
|
||
if self.seq_kd:
|
||
raise NotImplementedError('seq_kd=True (Sequential KD with teacher generation) is deprecated.')
|
||
|
||
# When using teacher_model_server, gkd_logits_topk is required (API only returns top-k logprobs)
|
||
if self.teacher_model_server is not None:
|
||
if self.gkd_logits_topk is None:
|
||
raise ValueError('gkd_logits_topk is required when using teacher_model_server')
|
||
|
||
# Validate gkd_logits_topk
|
||
if self.gkd_logits_topk is not None and self.gkd_logits_topk <= 0:
|
||
raise ValueError(f'gkd_logits_topk must be a positive integer, got {self.gkd_logits_topk}')
|
||
|
||
if self.gkd_logits_topk is not None and self.use_liger_kernel:
|
||
raise ValueError('gkd_logits_topk is not supported when using liger kernel')
|