SnowflakeCore-G1-Tiny2

A improve version of SnowflakeCore-G1-Tiny custom GPT-style transformer language model built from scratch using PyTorch, trained on the common-pile/wikimedia_filtered dataset.

Model Overview

SnowflakeCore-G1-Tiny2 is a GPT-style autoregressive transformer model with ~400M parameters designed for text generation tasks.

Key Features

• 2048 token context window for extended conversations
• Mixed precision training (BF16/FP16) for efficiency
• Custom attention implementation with fused operations
• Early stopping mechanisms for optimal training
• Gradient accumulation for effective large batch training

Architecture Specifications

Component	Value
Model Type	Autoregressive Transformer
Parameters	~400M
Layers	24
Hidden Size	1024
Attention Heads	16
Head Dimension	64
FFN Dimension	4096
Context Length	2048 tokens
Vocabulary Size	50,257 (GPT-2 tokenizer)

Model Benchmarks

The following benchmarks compare SnowflakeCore-G1-Tiny2, its predecessor, and GPT-2 on key performance and text quality metrics.

Performance & Quality Metrics

Model	Params	Size (MB)	Speed (tok/s)	Vocab Div.	Dist. Bigrams	Dist. Trigrams	Bigram Repet.	Trigram Repet.
SnowflakeCore-G1-Tiny2	355.9M	1357.54	22.13	0.3440	0.7408	0.8834	0.2592	0.1166
SnowflakeCore-G1-Tiny	355.9M	1357.54	22.12	0.2780	0.6111	0.7421	0.3889	0.2579
GPT-2 (small)	124.4M	474.70	47.73	0.2590	0.6408	0.7946	0.3592	0.2054

Notes:

• Vocabulary Diversity = unique tokens / total tokens
• Distinct N-grams = unique n-grams / total n-grams
• Lower repetition rates indicate better text novelty

Memory Usage (CPU)

All models report N/A for CPU memory usage across all sequence lengths.

Sequence Length	SnowflakeCore-G1-Tiny	SnowflakeCore-G1-Tiny2	GPT-2
128	N/A (CPU)	N/A (CPU)	N/A
512	N/A (CPU)	N/A (CPU)	N/A
1024	N/A (CPU)	N/A (CPU)	N/A
2048	N/A (CPU)	N/A (CPU)	N/A

Quick Start

Installation

pip install torch transformers # if not already installed

Basic Usage

from transformers import AutoModelForCausalLM, AutoTokenizer
import torch

# Load model and tokenizer
model = AutoModelForCausalLM.from_pretrained(
    "FlameF0X/SnowflakeCore-G1-Tiny2",
    trust_remote_code=True,
    force_download=True,
    use_safetensors=True,
)
tokenizer = AutoTokenizer.from_pretrained(
    "FlameF0X/SnowflakeCore-G1-Tiny2",
    trust_remote_code=True,
    force_download=True,
    use_safetensors=True,
)

def custom_greedy_generate(prompt, max_length=50):
    model.eval()
    input_ids = tokenizer(prompt, return_tensors="pt").input_ids
    generated = input_ids

    with torch.no_grad():
        for _ in range(max_length):
            outputs = model(input_ids=generated)
            next_token_logits = outputs["logits"][:, -1, :]
            next_token_id = torch.argmax(next_token_logits, dim=-1).unsqueeze(-1)
            generated = torch.cat((generated, next_token_id), dim=1)

            if next_token_id.item() == tokenizer.eos_token_id:
                break

    return tokenizer.decode(generated[0], skip_special_tokens=True)

# Generate text
prompt = "Once upon a time"
result = custom_greedy_generate(prompt)
print(result)

Fine-Tuning

... (same fine-tuning code as above) ...

Training Details

Dataset

• Source: common-pile/wikimedia_filtered

Training Configuration

• Framework: PyTorch with mixed precision (BF16/FP16)
• Optimizer: AdamW (learning rate: 2e-4)
• Batch Size: 1 with gradient accumulation (32 steps)
• Context Window: 2048 tokens
• Validation Split: 10%
• Early Stopping: Implemented at epoch and step levels

Performance Monitoring

• Training loss tracked per epoch with perplexity calculation
• Full validation after each epoch
• Step-level monitoring every 500 steps
• Comprehensive metrics saved in training_metrics.json

Technical Implementation

Attention Mechanism

• Causal Masking: Supports autoregressive generation
• Key Padding Mask: Enables batched inference
• Scaled Dot-Product: Head dimension normalization included

Memory Optimization

• Fused Operations: Reduces memory fragmentation
• Mixed Precision: 30-40% memory reduction
• Gradient Accumulation: Simulates larger batch sizes
• Optional Quantization: Further model compression

Training Stability

• Gradient Clipping: Prevents exploding gradients
• Automatic Loss Scaling: Mixed precision stability
• Early Stopping: Prevents overfitting with patience mechanisms

System Requirements

Memory Requirements

• Training: 16-24GB VRAM (precision dependent)
• Inference: 1-6GB VRAM for standard generation
• Context: Maximum 2048 tokens input length

Generation Parameters

Default configuration:

{
  "do_sample": true,
  "temperature": 1.0,
  "top_p": 0.9,
  "top_k": 50,
  "max_new_tokens": 50,
  "pad_token_id": 50256,
  "eos_token_id": 50256
}

Model Files

The repository contains:

• pytorch_model.bin - PyTorch model weights
• model.safetensors - SafeTensors format weights
• config.json - Model configuration
• generation_config.json - Generation parameters
• training_metrics.json - Training statistics
• tokenizer.json - Tokenizer configuration
• vocab.json & merges.txt - Vocabulary files

Limitations

• No HuggingFace .generate() support: Use custom generation function
• Output Quality: May produce repetitive or nonsensical text for some prompts
• Hardware Requirements: GPU recommended for practical inference
• Context Window: Limited to 2048 tokens
• Dataset Dependency: Performance tied to Mixture-of-Thoughts dataset quality

Example Output

N/A

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Small meta-data

• Release date: July 21, 2025.