LoRA Fine-Tuning Qwen-Chat Large Language Model (Single GPU)

Tongyi Qianwen is a large language model developed by Alibaba Cloud based on the Transformer architecture, trained on an extensive set of pre-training data. The pre-training data is diverse and covers a wide range, including a large amount of internet text, specialized books, code, etc. In addition, an AI assistant called Qwen-Chat has been created based on the pre-trained model using alignment mechanism.

This notebook uses Qwen-1.8B-Chat as an example to introduce how to LoRA fine-tune the Qianwen model using Deepspeed.

Environment Requirements

Please refer to requirements.txt to install the required dependencies.

Preparation

Download Qwen-1.8B-Chat

First, download the model files. You can choose to download directly from ModelScope.

python

from modelscope.hub.snapshot_download import snapshot_download
model_dir = snapshot_download('Qwen/Qwen-1_8B-Chat', cache_dir='.', revision='master')

Download Example Training Data

Download the data required for training; here, we provide a tiny dataset as an example. It is sampled from Belle.

Disclaimer: the dataset can be only used for the research purpose.

python

!wget https://atp-modelzoo-sh.oss-cn-shanghai.aliyuncs.com/release/tutorials/qwen_recipes/Belle_sampled_qwen.json

You can also refer to this format to prepare the dataset. Below is a simple example list with 1 sample:

json

[
  {
    "id": "identity_0",
    "conversations": [
      {
        "from": "user",
        "value": "你好"
      },
      {
        "from": "assistant",
        "value": "我是一个语言模型，我叫通义千问。"
      }
    ]
  }
]

You can also use multi-turn conversations as the training set. Here is a simple example:

json

[
  {
    "id": "identity_0",
    "conversations": [
      {
        "from": "user",
        "value": "你好，能告诉我遛狗的最佳时间吗？"
      },
      {
        "from": "assistant",
        "value": "当地最佳遛狗时间因地域差异而异，请问您所在的城市是哪里？"
      },
      {
        "from": "user",
        "value": "我在纽约市。"
      },
      {
        "from": "assistant",
        "value": "纽约市的遛狗最佳时间通常在早晨6点至8点和晚上8点至10点之间，因为这些时间段气温较低，遛狗更加舒适。但具体时间还需根据气候、气温和季节变化而定。"
      }
    ]
  }
]

Fine-Tune the Model

You can directly run the prepared training script to fine-tune the model.

python

!export CUDA_VISIBLE_DEVICES=0
!python ../../finetune.py \
    --model_name_or_path "Qwen/Qwen-1_8B-Chat/"\
    --data_path  "Belle_sampled_qwen.json"\
    --bf16 \
    --output_dir "output_qwen" \
    --num_train_epochs 5 \
    --per_device_train_batch_size 1 \
    --per_device_eval_batch_size 1 \
    --gradient_accumulation_steps 16 \
    --evaluation_strategy "no" \
    --save_strategy "steps" \
    --save_steps 1000 \
    --save_total_limit 10 \
    --learning_rate 1e-5 \
    --weight_decay 0.1 \
    --adam_beta2 0.95 \
    --warmup_ratio 0.01 \
    --lr_scheduler_type "cosine" \
    --logging_steps 1 \
    --report_to "none" \
    --model_max_length 512 \
    --gradient_checkpointing \
    --lazy_preprocess \
    --use_lora

Merge Weights

The training of both LoRA and Q-LoRA only saves the adapter parameters. You can load the fine-tuned model and merge weights as shown below:

python

from transformers import AutoModelForCausalLM
from peft import PeftModel
import torch

model = AutoModelForCausalLM.from_pretrained("Qwen/Qwen-1_8B-Chat/", torch_dtype=torch.float16, device_map="auto", trust_remote_code=True)
model = PeftModel.from_pretrained(model, "output_qwen/")
merged_model = model.merge_and_unload()
merged_model.save_pretrained("output_qwen_merged", max_shard_size="2048MB", safe_serialization=True)

The tokenizer files are not saved in the new directory in this step. You can copy the tokenizer files or use the following code:

python

from transformers import AutoTokenizer

tokenizer = AutoTokenizer.from_pretrained(
    "Qwen/Qwen-1_8B-Chat/",
    trust_remote_code=True
)

tokenizer.save_pretrained("output_qwen_merged")

Test the Model

After merging the weights, we can test the model as follows:

python

from transformers import AutoModelForCausalLM, AutoTokenizer
from transformers.generation import GenerationConfig

tokenizer = AutoTokenizer.from_pretrained("output_qwen_merged", trust_remote_code=True)
model = AutoModelForCausalLM.from_pretrained(
    "output_qwen_merged",
    device_map="auto",
    trust_remote_code=True
).eval()

response, history = model.chat(tokenizer, "你好", history=None)
print(response)