拉取 Llama2-Chinese

git clone https://github.com/FlagAlpha/Llama2-Chinese.git
cd Llama2-Chinese

安装依赖库:

pip install -r requirements.txt  -i https://pypi.tuna.tsinghua.edu.cn/simple #使用清华源安装

拉取 Llama2-Chinese-13b-Chat 模型权重及代码

git lfs install
git clone git clone https://huggingface.co/FlagAlpha/Llama2-Chinese-13b-Chat

执行git lfs install时如果报错

Git LFS is a command line extension and specification for managing large files with Git.
 The client is written in Go, with pre-compiled binaries available for Mac, Windows, Linux, and FreeBSD. Check out the website for an overview of features.
apt-get install git-lfs

查看文件详情 ls -l

-rw-r--r-- 1 root root        683 Aug  7 17:02 config.json
-rw-r--r-- 1 root root        175 Aug  7 17:02 generation_config.json
-rw-r--r-- 1 root root 9948728430 Aug  7 17:34 pytorch_model-00001-of-00003.bin
-rw-r--r-- 1 root root 9904165024 Aug  7 17:34 pytorch_model-00002-of-00003.bin
-rw-r--r-- 1 root root 6178983625 Aug  7 17:28 pytorch_model-00003-of-00003.bin
-rw-r--r-- 1 root root      33444 Aug  7 17:02 pytorch_model.bin.index.json
-rw-r--r-- 1 root root       1514 Aug  7 17:02 README.md
-rw-r--r-- 1 root root        414 Aug  7 17:02 special_tokens_map.json
-rw-r--r-- 1 root root        749 Aug  7 17:02 tokenizer_config.json
-rw-r--r-- 1 root root     499723 Aug  7 17:02 tokenizer.model

如果文件大小和数量不正确,说明权重文件下载失败,执行 rm -rf Llama2-Chinese-13b-Chat,再重新拉取(需要多试几次)。或者可以单独下载模型:

wget https://huggingface.co/FlagAlpha/Llama2-Chinese-13b-Chat/resolve/main/pytorch_model-00001-of-00003.bin
wget https://huggingface.co/FlagAlpha/Llama2-Chinese-13b-Chat/resolve/main/pytorch_model-00002-of-00003.bin
wget https://huggingface.co/FlagAlpha/Llama2-Chinese-13b-Chat/resolve/main/pytorch_model-00003-of-00003.bin

注:由于权重文件较大,且是hf是境外网站,经常会出现下载失败或者网速比较慢的情况,甚至会导致下载的模型文件缺失、运行时出现错误。正确的模型文件已上传至oss,可通过oss直接下载,速度快。

在Llama2-Chinese目录下创建一个python文件 generate.py

import torch
from transformers import AutoTokenizer, AutoModelForCausalLM
model = AutoModelForCausalLM.from_pretrained('Llama2-Chinese-13b-Chat',device_map='auto',torch_dtype=torch.float16,load_in_8bit=True)
model =model.eval()
tokenizer = AutoTokenizer.from_pretrained('Llama2-Chinese-13b-Chat',use_fast=False)
tokenizer.pad_token = tokenizer.eos_token
input_ids = tokenizer(['<s>Human: 介绍一下华南理工大学\n</s><s>Assistant: '], return_tensors="pt",add_special_tokens=False).input_ids.to('cuda')  
generate_input = {
    "input_ids":input_ids,
    "max_new_tokens":512,
    "do_sample":True,
    "top_k":50,
    "top_p":0.95,
    "temperature":0.3,
    "repetition_penalty":1.3,
    "eos_token_id":tokenizer.eos_token_id,
    "bos_token_id":tokenizer.bos_token_id,
    "pad_token_id":tokenizer.pad_token_id
generate_ids  = model.generate(**generate_input)
text = tokenizer.decode(generate_ids[0])
print(text)

执行 python generate.py,看到输出结果:

可见该模型存在许多事实性错误,中文组织能力弱。

首先准备自己的训练数据和验证数据(csv格式):

每个csv文件中包含一列“text”,每一行为一个训练样例,每个训练样例按照以下格式将问题和答案组织为模型输入

按照以下格式自定义训练和验证数据集:

"<s>Human: "+问题+"\n</s><s>Assistant: "+答案
<s>Human: 你是谁?</s><s>Assistant: 我是Llama-Chinese-13B-chat,一个由小明在2023年开发的人工智能助手。</s>

将数据上传至特定的文件夹内。

然后修改微调的脚本 train/sft/finetune.sh参数,主要修改模型输出路径、原始模型路径、训练数据与验证数据路径:

bash finetune.sh

开始微调训练,得到微调后的模型:

得到生成模型后,新建一个python文件:merge.py,用于融合原模型和新生成的模型文件(参考代码附于文末

import argparse
import json
import os
import gc
import torch
import sys
sys.path.append("./")
import peft
from peft import PeftModel
from transformers import LlamaForCausalLM, LlamaTokenizer
from huggingface_hub import hf_hub_download
parser = argparse.ArgumentParser()
parser.add_argument('--base_model', default=None, required=True,
                    type=str, help="Please specify a base_model")
parser.add_argument('--lora_model', default=None, required=True,
                    type=str, help="Please specify LoRA models to be merged (ordered); use commas to separate multiple LoRA models.")
parser.add_argument('--offload_dir', default=None, type=str,
                    help="(Optional) Please specify a temp folder for offloading (useful for low-RAM machines). Default None (disable offload).")
parser.add_argument('--output_type', default='pth',choices=['pth','huggingface'], type=str,
                    help="save the merged model in pth or huggingface format.")
parser.add_argument('--output_dir', default='./', type=str)
emb_to_model_size = {
    4096 : '7B',
    5120 : '13B',
    6656 : '30B',
    8192 : '65B',
num_shards_of_models = {'7B': 1, '13B': 2}
params_of_models = {
    '7B':
        "dim": 4096,
        "multiple_of": 256,
        "n_heads": 32,
        "n_layers": 32,
        "norm_eps": 1e-06,
        "vocab_size": -1,
    '13B':
        "dim": 5120,
        "multiple_of": 256,
        "n_heads": 40,
        "n_layers": 40,
        "norm_eps": 1e-06,
        "vocab_size": -1,
def transpose(weight, fan_in_fan_out):
    return weight.T if fan_in_fan_out else weight
# Borrowed and modified from https://github.com/tloen/alpaca-lora
def translate_state_dict_key(k):
    k = k.replace("base_model.model.", "")
    if k == "model.embed_tokens.weight":
        return "tok_embeddings.weight"
    elif k == "model.norm.weight":
        return "norm.weight"
    elif k == "lm_head.weight":
        return "output.weight"
    elif k.startswith("model.layers."):
        layer = k.split(".")[2]
        if k.endswith(".self_attn.q_proj.weight"):
            return f"layers.{layer}.attention.wq.weight"
        elif k.endswith(".self_attn.k_proj.weight"):
            return f"layers.{layer}.attention.wk.weight"
        elif k.endswith(".self_attn.v_proj.weight"):
            return f"layers.{layer}.attention.wv.weight"
        elif k.endswith(".self_attn.o_proj.weight"):
            return f"layers.{layer}.attention.wo.weight"
        elif k.endswith(".mlp.gate_proj.weight"):
            return f"layers.{layer}.feed_forward.w1.weight"
        elif k.endswith(".mlp.down_proj.weight"):
            return f"layers.{layer}.feed_forward.w2.weight"
        elif k.endswith(".mlp.up_proj.weight"):
            return f"layers.{layer}.feed_forward.w3.weight"
        elif k.endswith(".input_layernorm.weight"):
            return f"layers.{layer}.attention_norm.weight"
        elif k.endswith(".post_attention_layernorm.weight"):
            return f"layers.{layer}.ffn_norm.weight"
        elif k.endswith("rotary_emb.inv_freq") or "lora" in k:
            return None
        else:
            print(layer, k)
            raise NotImplementedError
    else:
        print(k)
        raise NotImplementedError
def unpermute(w):
    return (
        w.view(n_heads, 2, dim // n_heads // 2, dim).transpose(1, 2).reshape(dim, dim)
def save_shards(model_sd, num_shards: int):
    # Add the no_grad context manager
    with torch.no_grad():
        if num_shards == 1:
            new_state_dict = {}
            for k, v in model_sd.items():
                new_k = translate_state_dict_key(k)
                if new_k is not None:
                    if "wq" in new_k or "wk" in new_k:
                        new_state_dict[new_k] = unpermute(v)
                    else:
                        new_state_dict[new_k] = v
            os.makedirs(output_dir, exist_ok=True)
            print(f"Saving shard 1 of {num_shards} into {output_dir}/consolidated.00.pth")
            torch.save(new_state_dict, output_dir + "/consolidated.00.pth")
            with open(output_dir + "/params.json", "w") as f:
                json.dump(params, f)
        else:
            new_state_dicts = [dict() for _ in range(num_shards)]
            for k in list(model_sd.keys()):
                v = model_sd[k]
                new_k = translate_state_dict_key(k)
                if new_k is not None:
                    if new_k=='tok_embeddings.weight':
                        print(f"Processing {new_k}")
                        assert v.size(1)%num_shards==0
                        splits = v.split(v.size(1)//num_shards,dim=1)
                    elif new_k=='output.weight':
                        print(f"Processing {new_k}")
                        splits = v.split(v.size(0)//num_shards,dim=0)
                    elif new_k=='norm.weight':
                        print(f"Processing {new_k}")
                        splits = [v] * num_shards
                    elif 'ffn_norm.weight' in new_k:
                        print(f"Processing {new_k}")
                        splits = [v] * num_shards
                    elif 'attention_norm.weight' in new_k:
                        print(f"Processing {new_k}")
                        splits = [v] * num_shards
                    elif 'w1.weight' in new_k:
                        print(f"Processing {new_k}")
                        splits = v.split(v.size(0)//num_shards,dim=0)
                    elif 'w2.weight' in new_k:
                        print(f"Processing {new_k}")
                        splits = v.split(v.size(1)//num_shards,dim=1)
                    elif 'w3.weight' in new_k:
                        print(f"Processing {new_k}")
                        splits = v.split(v.size(0)//num_shards,dim=0)
                    elif 'wo.weight' in new_k:
                        print(f"Processing {new_k}")
                        splits = v.split(v.size(1)//num_shards,dim=1)
                    elif 'wv.weight' in new_k:
                        print(f"Processing {new_k}")
                        splits = v.split(v.size(0)//num_shards,dim=0)
                    elif "wq.weight" in new_k or "wk.weight" in new_k:
                        print(f"Processing {new_k}")
                        v = unpermute(v)
                        splits = v.split(v.size(0)//num_shards,dim=0)
                    else:
                        print(f"Unexpected key {new_k}")
                        raise ValueError
                    for sd,split in zip(new_state_dicts,splits):
                        sd[new_k] = split.clone()
                        del split
                    del splits
                del model_sd[k],v
                gc.collect()    # Effectively enforce garbage collection
            os.makedirs(output_dir, exist_ok=True)
            for i,new_state_dict in enumerate(new_state_dicts):
                print(f"Saving shard {i+1} of {num_shards} into {output_dir}/consolidated.0{i}.pth")
                torch.save(new_state_dict, output_dir + f"/consolidated.0{i}.pth")
            with open(output_dir + "/params.json", "w") as f:
                print(f"Saving params.json into {output_dir}/params.json")
                json.dump(params, f)
if __name__=='__main__':
    args = parser.parse_args()
    base_model_path = args.base_model
    lora_model_paths = [s.strip() for s in args.lora_model.split(',') if len(s.strip())!=0]
    output_dir = args.output_dir
    output_type = args.output_type
    offload_dir = args.offload_dir
    print(f"Base model: {base_model_path}")
    print(f"LoRA model(s) {lora_model_paths}:")
    if offload_dir is not None:
        # Load with offloading, which is useful for low-RAM machines.
        # Note that if you have enough RAM, please use original method instead, as it is faster.
        base_model = LlamaForCausalLM.from_pretrained(
            base_model_path,
            load_in_8bit=False,
            torch_dtype=torch.float16,
            offload_folder=offload_dir,
            offload_state_dict=True,
            low_cpu_mem_usage=True,
            device_map={"": "cpu"},
    else:
        # Original method without offloading
        base_model = LlamaForCausalLM.from_pretrained(
            base_model_path,
            load_in_8bit=False,
            torch_dtype=torch.float16,
            device_map={"": "cpu"},
    print(base_model)
    ## infer the model size from the checkpoint
    embedding_size = base_model.get_input_embeddings().weight.size(1)
    model_size = emb_to_model_size[embedding_size]
    print(f"Peft version: {peft.__version__}")
    print(f"Loading LoRA for {model_size} model")
    lora_model = None
    lora_model_sd = None
    for lora_index, lora_model_path in enumerate(lora_model_paths):
        print(f"Loading LoRA {lora_model_path}")
        tokenizer = LlamaTokenizer.from_pretrained(lora_model_path)
        assert base_model.get_input_embeddings().weight.size(0) == len(tokenizer)
        # if base_model.get_input_embeddings().weight.size(0) != len(tokenizer):
        #     base_model.resize_token_embeddings(len(tokenizer))
        #     print(f"Extended vocabulary size to {len(tokenizer)}")
        first_weight = base_model.model.layers[0].self_attn.q_proj.weight
        first_weight_old = first_weight.clone()
        if hasattr(peft.LoraModel, 'merge_and_unload'):
            lora_model = PeftModel.from_pretrained(
                base_model,
                lora_model_path,
                device_map={"": "cpu"},
                torch_dtype=torch.float16,
            assert torch.allclose(first_weight_old, first_weight)
            print(f"Merging with merge_and_unload...")
            base_model = lora_model.merge_and_unload()
        else:
            base_model_sd = base_model.state_dict()
                lora_model_sd = torch.load(os.path.join(lora_model_path,'adapter_model.bin'),map_location='cpu')
            except FileNotFoundError:
                print("Cannot find lora model on the disk. Downloading lora model from hub...")
                filename = hf_hub_download(repo_id=lora_model_path,filename='adapter_model.bin')
                lora_model_sd = torch.load(filename,map_location='cpu')
            lora_config = peft.LoraConfig.from_pretrained(lora_model_path)
            lora_scaling = lora_config.lora_alpha / lora_config.r
            fan_in_fan_out = lora_config.fan_in_fan_out
            lora_keys = [k for k in lora_model_sd if 'lora_A' in k]
            non_lora_keys = [k for k in lora_model_sd if not 'lora_' in k]
            for k in non_lora_keys:
                print(f"merging {k}")
                original_k = k.replace('base_model.model.','')
                base_model_sd[original_k].copy_(lora_model_sd[k])
            for k in lora_keys:
                print(f"merging {k}")
                original_key = k.replace('.lora_A','').replace('base_model.model.','')
                assert original_key in base_model_sd
                lora_a_key = k
                lora_b_key = k.replace('lora_A','lora_B')
                base_model_sd[original_key] += (
                    transpose(lora_model_sd[lora_b_key].float() @ lora_model_sd[lora_a_key].float(),fan_in_fan_out) * lora_scaling
                assert base_model_sd[original_key].dtype == torch.float16
        # did we do anything?
        assert not torch.allclose(first_weight_old, first_weight)
    tokenizer.save_pretrained(output_dir)
    if output_type=='huggingface':
        print("Saving to Hugging Face format...")
        LlamaForCausalLM.save_pretrained(
            base_model, output_dir,
            max_shard_size="2GB"
        ) #, state_dict=deloreanized_sd)
    else: # output_type=='pth
        print("Saving to pth format...")
        base_model_sd = base_model.state_dict()
        del lora_model, base_model, lora_model_sd
        params = params_of_models[model_size]
        num_shards = num_shards_of_models[model_size]
        n_layers = params["n_layers"]
        n_heads = params["n_heads"]
        dim = params["dim"]
        dims_per_head = dim // n_heads
        base = 10000.0
        inv_freq = 1.0 / (base ** (torch.arange(0, dims_per_head, 2).float() / dims_per_head))
        save_shards(model_sd=base_model_sd, num_shards=num_shards)

调用方法:

CUDA_VISIBLE_DEVICES="3" python merge.py \   
 --base_model /hy-tmp/Llama2-Chinese/Llama2-Chinese-13b-Chat \  
 --lora_model /hy-tmp/Llama2-Chinese/train/sft/output \  
 --output_type huggingface \  
 --output_dir ./output_merge

注 : base_model 为原模型路径,lora_model 为训练后生成模型了路径 , output_dir 为合并后模型生成路径

执行代码合并成功后,可以看见在输出目录出现新的模型:

![1691488726355](image/Llama2-Chinese-13b-Chat/1691488726355.png)

获得新模型后,修改 generate.py中的模型路径为 output_dir

开始运行测试:python generate.py

对比原输出,可以看出微调效果明显:

Llama2基座模型增量预训练

AI模型的训练训练过程分为如下三个阶段
第一个阶段叫做无监督学习(PreTraining),就是输入大量的文本语料让GPT自己寻找语言的规律, 这样一个巨大的词向量空间就形成了,但是话说的漂亮并不一定正确。
第二个阶段叫做监督学习(Supervised Fine-Tuning,也叫微调),就是人工标注一些语料,教会GPT什 么该说,什么不该说。(训练数据集)
第三个阶段叫做强化学习(RM,也叫奖励模型训练),就是给GPT的回答进行打分,告诉他在他 的一众回答中,哪些回答更好。(验证数据集)

第一个阶段(无监督学习)分为了底座模型预训练,及增量预训练,它们都属于无监督学习,接下来基于Llama2底座模型继续使用大量文本进行增量预训练。

经测试,训练的硬件需求至少需要6张40G*A100。

1.环境准备

在提供的预训练文件夹中,下载原始模型,放入 llama_script/training/pretrained_model目录下

拉取transformers项目并安装依赖

git clone https://github.com/huggingface/transformers.git
pip install -e .

在后续的训练中,需要使用到HuggingFace格式的基座模型。如果下载了官网的PyTorch版本,需重新下载,也可使用transformers中的脚本转换为HuggingFace格式。

cd /transformers
python src/transformers/models/llama/convert_llama_weights_to_hf.py
 --input_dir ./llama
 --model_size 7B
 --output_dir ./output

2.数据准备

将数据按照段落划分为多个txt文件,每个文件中只包含一个段落,且段落被包含在 <s> </s>内:

将上述的文本数据放入文件夹下的 dataset_dir目录下。

3.开始训练

进入项目的 train目录下,修改 pretrain脚本参数,主要修改 model_name_or_path(基座模型路径)tokenizer_name_or_path(分词器路径)dataset_dir(数据集路径)参数(若已经按照前面的步骤放在指定的文件夹下,则不需要修改。)

开始训练,默认使用单卡训练,如需使用多卡,修改脚本中 nproc_per_node参数

cd training
bash pretrain.sh

4.合并文件

训练后的LoRA权重和配置存放于output/pt_lora_model中,运行文件夹中的合并代码:

python merge_llama.py --base_model /hy-tmp/Llama-2-7b-hf  --lora_model /hy-tmp/output_dir/pt_lora_model   --output_dir /hy-tmp/output_merge  --output_type huggingface

根据实际情况修改参数的路径以及输出类型,即可开始合并。

5.推理测试

调用生成代码进行测试,结果如下:

原始模型:

可见经过增量预训练,模型成功学习了新知识。