abhinavv3/GPT-124m

MEMGPT

A GPT-2-style large language model (LLM) repository.This implementation includes full support for distributed training, sharded datasets, benchmark evaluation, and efficient text generation.

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🔧 Features

• Transformer architecture based on GPT-2.
• Configurable training and model hyperparameters via JSON.
• Sharded dataset loading from .npy files.
• Mixed-precision training with torch.autocast.
• DDP (DistributedDataParallel) support.
• Evaluation support with HellaSwag.
• Modular codebase for easy extensibility.

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📁 Project Structure

MEMGPT/
├── configs/
│   └── config.json                    # Model and training configuration
│
├── data/
│   ├── edu_fineweb/                   # Sharded training data
│   │   ├── train_000001.npy
│   │   ├── train_000002.npy
│   │   └── test_000001.npy
│   ├── hellaswag/
│   │   └── hellaswag_val.jsonl
│   └── fineweb.py                     # Dataset sharding/processing logic
│
├── model_core/
│   ├── __init__.py
│   ├── attention.py                   # Self-attention module
│   ├── model.py                       # GPT2 model architecture
│   ├── dataloader.py                  # DataLoader_1 class
│   └── training.py                    # train_nanogpt function
│
├── scripts/
│   ├── train.py                       # Entry point to start training
│   ├── evaluate.py                    # Run evaluation
│   └── generate.py                    # Generate text from trained model
│
├── evaluation/
│   ├── __init__.py
│   ├── hellaswag.py                   # HellaSwag dataset preparation
│   └── val_hellaswag.py               # HellaSwag scoring function
│
├── logs/
│   ├── log.txt                        # Training log file
│   └── model_xxxxx.pt                # Checkpoint files
│
├── .gitignore
├── README.md
├── requirements.txt

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⚙️ Configuration

Edit configs/config.json to configure your model and training setup.

Example:

{
  "model": {
    "block_size": 1024,
    "vocab_size": 50304,
    "n_layer": 12,
    "n_head": 12,
    "n_embd": 768
  },
  "training": {
    "max_steps": 19073,
    "log_dir": "log",
    "total_batch_size": 524288,
    "B": 64,
    "T": 1024,
    "max_lr": 0.0006,
    "min_lr": 0.00006,
    "warmup_steps": 715,
    "weight_decay": 0.1,
    "learning_rate": 0.0006
  }
}

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🚀 Training

To start training the model:

python scripts/train.py

This script internally loads train_nanogpt() from model_core/training.py using the config in configs/config.json.

Optional: Distributed Training

To run training across multiple GPUs using PyTorch DDP:

torchrun --nproc_per_node=NUM_GPUS scripts/train.py

Replace NUM_GPUS with the number of GPUs you want to use.

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📊 Evaluation

To evaluate on HellaSwag:

python scripts/evaluate.py

Make sure the hellaswag_val.jsonl file is available under data/hellaswag/.

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✍️ Text Generation

To generate text from a trained model:

python scripts/generate.py

Make sure to adjust the generation script to point to the correct checkpoint under the logs/ directory.

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🧩 Requirements

Install required packages:

pip install -r requirements.txt

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📌 Notes

• Ensure your .npy sharded data is placed under data/edu_fineweb/.
• The log directory and checkpoints will be saved in logs/.
• The DataLoader_1 handles distributed data loading.
• Supports bfloat16 autocasting for better training efficiency.

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📮 License

MIT License. Feel free to modify and build upon this for research or commercial use.

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🙌 Acknowledgements

Inspired by Andrej Karpathy's nanoGPT. Special thanks to the Andrej Karpathy Youtube tutorials and open-source AI community.