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---
license: apache-2.0
---
# ReplaceMe: Training-Free Transformer Pruning via Layer Removal & Linear Transformations
[](https://arxiv.org/abs/2505.02819)
[](https://opensource.org/licenses/Apache-2.0)

## Model Description
ReplaceMe is a novel method for transformer model compression that enables **training-free** block/layer pruning while maintaining model performance through linear transformations. The approach:
- Identifies and removes block of layers
- Applies mathematically-derived transformations to preserve information flow
- Requires no fine-tuning or retraining
- Works with standard transformer architectures (The LTs are merged with the original model weights)
## Key Features
- π **Zero-Training Pruning**: Remove layers without any fine-tuning
- π§ **Performance Preservation**: <8% accuracy drop in most cases
- β‘ **Instant Speedup**: less blocks -> faster inference + less memory
- π **Plug-and-Play**: Works with existing HuggingFace models
## π₯ Performance Comparison of Pruning Methods (Llama 2 7B, 25% Compression)
| Method | num_pruned_layers | Dataset | State | race π | winogrande π² | piqa π§ | boolq β | openbookqa π | sciq π¬ | lambada_openai π¦ | ppl | Avg-acc π |
|-----------------------|-------------------|------------|---------------|--------|--------------|--------|---------|--------------|--------|------------------|-----------|------------|
| | | | | acc | acc | acc_norm | acc | acc_norm | acc_norm | acc | | |
| **Llama 3.1** (baseline) | - | - | - | 0.450 | 0.779 | 0.810 | 0.842 | 0.430 | 0.961 | 0.732 | 3.404 | **0.712** |
| **UIDL*** | 8 | slim_orca | no training | 0.341 | 0.719 | 0.690 | 0.773 | 0.310 | 0.719 | 0.087 | 932.000 | 0.592 |
| **ReplaceMe** (Ours) β
| 8 | slim_orca | no training | 0.406 | **0.742** π | 0.706 | 0.830 | 0.338 | 0.901 | 0.471 | 16.760 | 0.654 |
| **ReplaceMe** (Ours) β | 8 | slim_orca | SFT | **0.431** π | 0.716 | **0.728** π | **0.849** π | **0.378** π | **0.912** π | **0.697** π | 4.04 π | **0.669** π |
**Key:**
- π Best performance in column
- β
Training-free (our methods)
- β Requires training
**Metrics Explained:**
- **Bold**: Best training-free results
- All numbers are accuracy scores
> π₯ **Our Healed model can acheive 94.0% of baseline performance after healing on 1B tokens!**
## Installation
```bash
pip install replaceme
# or
git clone https://github.com/mts-ai/ReplaceMe
cd ReplaceMe
pip install -e .
```
## Basic Usage
```
# LSTSQ method (recommended)
run_replaceme --config ./reproduce/Replace_Me_pipeline_lstsq.yaml
# Cosine similarity method
run_replaceme --config ./reproduce/Replace_Me_pipeline_cosine.yaml
```
There are many parameters you can play with, visit our repo and dscover π₯π₯
## Load Model
As we said we are merging the LTs with the original transformer architecture so you just do it as usual
```python
## EXAMPLE
from transformers import AutoModelForCausalLM, AutoTokenizer
model_name = "MTSAIR/Llama3.1-6B-ReplaceMe-Healed"
model = AutoModelForCausalLM.from_pretrained(
model_name,
torch_dtype="auto",
device_map="auto"
)
tokenizer = AutoTokenizer.from_pretrained(model_name)
prompt = "What is ReplaceME pruning method?!"
messages = [
{"role": "user", "content": prompt}
]
text = tokenizer.apply_chat_template(
messages,
tokenize=False,
add_generation_prompt=True
)
model_inputs = tokenizer([text], return_tensors="pt").to(model.device)
output = model.generate(
**model_inputs,
max_new_tokens=512
)
response = tokenizer.batch_decode(output, skip_special_tokens=True)[0]
```
# Citation
If you use ReplaceMe in your research, please cite our paper:
```bibtex
@article{shopkhoev2025replaceme0,
title = {ReplaceMe: Network Simplification via Layer Pruning and Linear Transformations},
author = {Dmitriy Shopkhoev and Ammar Ali and Magauiya Zhussip and Valentin Malykh and Stamatios Lefkimmiatis and Nikos Komodakis and Sergey Zagoruyko},
year = {2025},
journal = {arXiv preprint arXiv: 2505.02819}
}
``` |