Saved in:
Bibliographic Details
Main Authors: He, Yifei, Zeng, Siqi, Hu, Yuzheng, Yang, Rui, Zhang, Tong, Zhao, Han
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2505.10833
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908600332451840
author He, Yifei
Zeng, Siqi
Hu, Yuzheng
Yang, Rui
Zhang, Tong
Zhao, Han
author_facet He, Yifei
Zeng, Siqi
Hu, Yuzheng
Yang, Rui
Zhang, Tong
Zhao, Han
contents Model merging provides a scalable alternative to multi-task training by combining specialized finetuned models through parameter arithmetic, enabling efficient deployment without the need for joint training or access to all task data. While recent methods have shown promise, existing evaluations are limited in both model scale and task diversity, leaving open questions about their applicability to large, domain-specialized LLMs. To tackle the challenges, we introduce MergeBench, a comprehensive evaluation suite designed to assess model merging at scale. MergeBench builds on state-of-the-art open-source language models, including Llama and Gemma families at 2B to 9B scales, and covers five key domains: instruction following, mathematics, multilingual understanding, coding and safety. We standardize finetuning and evaluation protocols, and assess eight representative merging methods across multi-task performance, forgetting and runtime efficiency. Based on extensive experiments, we provide practical guidelines for algorithm selection and share insights showing that model merging tends to perform better on stronger base models, with techniques such as merging coefficient tuning and sparsification improving knowledge retention. However, several challenges remain, including the computational cost on large models, the gap for in-domain performance compared to multi-task models, and the underexplored role of model merging in standard LLM training pipelines. We hope MergeBench provides a foundation for future research to advance the understanding and practical application of model merging. Our project page is at \href{https://yifei-he.github.io/mergebench/}{https://yifei-he.github.io/mergebench/}.
format Preprint
id arxiv_https___arxiv_org_abs_2505_10833
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle MergeBench: A Benchmark for Merging Domain-Specialized LLMs
He, Yifei
Zeng, Siqi
Hu, Yuzheng
Yang, Rui
Zhang, Tong
Zhao, Han
Machine Learning
Model merging provides a scalable alternative to multi-task training by combining specialized finetuned models through parameter arithmetic, enabling efficient deployment without the need for joint training or access to all task data. While recent methods have shown promise, existing evaluations are limited in both model scale and task diversity, leaving open questions about their applicability to large, domain-specialized LLMs. To tackle the challenges, we introduce MergeBench, a comprehensive evaluation suite designed to assess model merging at scale. MergeBench builds on state-of-the-art open-source language models, including Llama and Gemma families at 2B to 9B scales, and covers five key domains: instruction following, mathematics, multilingual understanding, coding and safety. We standardize finetuning and evaluation protocols, and assess eight representative merging methods across multi-task performance, forgetting and runtime efficiency. Based on extensive experiments, we provide practical guidelines for algorithm selection and share insights showing that model merging tends to perform better on stronger base models, with techniques such as merging coefficient tuning and sparsification improving knowledge retention. However, several challenges remain, including the computational cost on large models, the gap for in-domain performance compared to multi-task models, and the underexplored role of model merging in standard LLM training pipelines. We hope MergeBench provides a foundation for future research to advance the understanding and practical application of model merging. Our project page is at \href{https://yifei-he.github.io/mergebench/}{https://yifei-he.github.io/mergebench/}.
title MergeBench: A Benchmark for Merging Domain-Specialized LLMs
topic Machine Learning
url https://arxiv.org/abs/2505.10833