train.py

import os
os.environ["WANDB_PROJECT"]= "lmms-ft"
from dataclasses import asdict
import math
from pathlib import Path
from typing import List, Optional
import yaml

from accelerate.utils import DistributedType
from peft import LoraConfig, get_peft_model, prepare_model_for_kbit_training
import torch
import transformers
from transformers import Trainer, deepspeed


from arguments import ModelArguments, DataArguments, TrainingArguments, LoraArguments
from collators import COLLATORS
from datasets import LazySupervisedDataset
from loaders import LOADERS
from supported_models import MODULE_KEYWORDS
from utils import (
    rank0_print, find_all_linear_names, safe_save_model_for_hf_trainer,
    get_peft_state_maybe_zero_3, TrainerWithCustomSampler
)


def train():
    parser = transformers.HfArgumentParser(
        (ModelArguments, DataArguments, TrainingArguments, LoraArguments)
    )
    model_args, data_args, training_args, lora_args = parser.parse_args_into_dataclasses()

    # dumping arguments
    output_dir = getattr(training_args, 'output_dir', None)
    assert output_dir is not None, "output_dir is required"
    args_dir = Path(output_dir) / "arguments"
    args_dir.mkdir(parents=True, exist_ok=True)
    yaml.dump(asdict(model_args), open(args_dir / "model.yaml", "w"))
    yaml.dump(asdict(data_args), open(args_dir / "data.yaml", "w"))
    yaml.dump(asdict(training_args), open(args_dir / "training.yaml", "w"))
    yaml.dump(asdict(lora_args), open(args_dir / "lora.yaml", "w"))

    compute_dtype = (torch.float16 if training_args.fp16 else (torch.bfloat16 if training_args.bf16 else torch.float32))
    if getattr(training_args, 'deepspeed', None) and getattr(lora_args, 'q_lora', False):
        training_args.distributed_state.distributed_type = DistributedType.DEEPSPEED

    device_map = None
    if lora_args.q_lora:
        device_map = {"": int(os.environ.get("LOCAL_RANK") or 0)} if int(os.environ.get("WORLD_SIZE", 1)) != 1 else None
        if len(training_args.fsdp) > 0 or deepspeed.is_deepspeed_zero3_enabled():
            raise ValueError("FSDP or ZeRO3 are not incompatible with QLoRA.")

    # llm quantization config (for q-lora)
    bnb_config = None
    if lora_args.use_lora and lora_args.q_lora:
        from transformers import BitsAndBytesConfig
        rank0_print("Quantization for LLM enabled...")
        bnb_config = BitsAndBytesConfig(
            load_in_4bit=True,
            bnb_4bit_compute_dtype=compute_dtype,
            bnb_4bit_quant_type="nf4", 
        )
    
    # load model, tokenizer, processor
    rank0_print("Loading model, tokenizer, processor...")
    loader = LOADERS[model_args.model_family_id](
        model_hf_path=model_args.model_hf_path,
        model_local_path=model_args.model_local_path,
        compute_dtype=compute_dtype,
        bnb_config=bnb_config,
        use_flash_attn=training_args.use_flash_attn,
        device_map=device_map,
    )
    model, tokenizer, processor, config = loader.load()
    tokenizer.model_max_length = training_args.model_max_length

    if training_args.gradient_checkpointing:
        model.enable_input_require_grads()

    # freeze certain params
    vision_encoder_keys = MODULE_KEYWORDS[model_args.model_family_id]["vision_encoder"]
    if not training_args.train_vision_encoder:
        rank0_print(f"Vision encoder is freezed... including:")
        for module in vision_encoder_keys:
            rank0_print(f"\t{module}")
            eval(f"model.{module}").requires_grad_(False)

    vision_projector_keys = MODULE_KEYWORDS[model_args.model_family_id]["vision_projector"]
    if not training_args.train_vision_projector:
        rank0_print(f"Vision projector is freezed... including:")
        for module in vision_projector_keys:
            rank0_print(f"\t{module}")
            eval(f"model.{module}").requires_grad_(False)

    # other components preparation (e.g., image_newline, vision_resampler)
    # we will just freeze these
    if "others" in MODULE_KEYWORDS[model_args.model_family_id]:
        rank0_print(f"Other multimodal component is freezed... including:")
        for other_key in MODULE_KEYWORDS[model_args.model_family_id]["others"]:
            rank0_print(f"\t{other_key}")
            eval(f"model.{other_key}").requires_grad_(False)

    # lora preparation
    llm_keys = MODULE_KEYWORDS[model_args.model_family_id]["llm"]
    if not (lora_args.use_lora or (training_args.train_vision_encoder and lora_args.use_vision_lora)):
        rank0_print("No LoRA enabled...")        
    else:
        named_modules = {n: m for n, m in model.named_modules()}
        lora_modules = []
        full_modules = []

        if training_args.train_vision_encoder and lora_args.use_vision_lora:
            rank0_print("LoRA for vision encoder enabled...")
            lora_modules.extend(find_all_linear_names(named_modules, vision_encoder_keys))
        elif training_args.train_vision_encoder:
            rank0_print("Vision encoder will be fully trained...")
            full_modules.extend(vision_encoder_keys)
        
        if lora_args.use_lora:
            rank0_print("LoRA for LLM enabled...")
            lora_modules.extend(find_all_linear_names(named_modules, llm_keys))
        else:
            rank0_print("LLM will be fully trained...")
            full_modules.extend(llm_keys)
        
        if training_args.train_vision_projector:
            rank0_print("Vision projector will be fully trained...")
            full_modules.extend(vision_projector_keys)
        
        lora_config = LoraConfig(
            r=lora_args.lora_r,
            lora_alpha=lora_args.lora_alpha,
            target_modules=lora_modules,
            modules_to_save=full_modules,
            lora_dropout=lora_args.lora_dropout,
            bias=lora_args.lora_bias,
            task_type="CAUSAL_LM",
        )

        if lora_args.q_lora:
            model = prepare_model_for_kbit_training(
                model, use_gradient_checkpointing=training_args.gradient_checkpointing
            )
            
        model = get_peft_model(model, lora_config)
        
    # print trainable parameters for inspection
    rank0_print("Trainable parameters:")
    for name, param in model.named_parameters():
        if param.requires_grad:
            rank0_print(f"\t{name}")

    # load data
    rank0_print("Loading data...")
    train_dataset = LazySupervisedDataset(
        data_path=data_args.data_path,
        image_folder=data_args.image_folder,
        video_folder=data_args.video_folder,
        num_frames=data_args.num_frames,
        model_family_id=model_args.model_family_id,
        user_key=data_args.user_key,
        assistant_key=data_args.assistant_key
    )
    if data_args.eval_data_path:
        eval_dataset = LazySupervisedDataset(
            data_path=data_args.eval_data_path,
            image_folder=data_args.image_folder,
            video_folder=data_args.video_folder,
            num_frames=data_args.num_frames,
            model_family_id=model_args.model_family_id,
            user_key=data_args.user_key,
            assistant_key=data_args.assistant_key
        )
    else:
        eval_dataset = None
        training_args.eval_strategy = "no"

    # data collator
    data_collator = COLLATORS[model_args.model_family_id](
        config=config,
        tokenizer=tokenizer,
        processor=processor,
        mask_question_tokens=training_args.mask_question_tokens
    )

    # trainer
    trainer = TrainerWithCustomSampler(
        model=model,
        args=training_args,
        data_collator=data_collator,
        train_dataset=train_dataset,
        eval_dataset=eval_dataset,
    )
    trainer.train()
    trainer.save_state()

    safe_save_model_for_hf_trainer(trainer=trainer, output_dir=output_dir)
    

if __name__ == "__main__":
    train()