Parameter-Efficient Fine-Tuning without Introducing New Latency

TL;DR

This paper introduces a parameter-efficient fine-tuning method that uses a shared, task-agnostic sparse mask and a novel adapter technique, achieving state-of-the-art results without increasing inference latency or storage requirements.

Contribution

It proposes a new PEFT approach with a shared sparse mask and direct adapter application, improving performance and efficiency without added latency.

Findings

Surpasses existing PEFT methods on GLUE benchmark

Stores only 0.03% of parameters compared to full fine-tuning

Achieves state-of-the-art performance in efficiency and accuracy

Abstract

Parameter-efficient fine-tuning (PEFT) of pre-trained language models has recently demonstrated remarkable achievements, effectively matching the performance of full fine-tuning while utilizing significantly fewer trainable parameters, and consequently addressing the storage and communication constraints. Nonetheless, various PEFT methods are limited by their inherent characteristics. In the case of sparse fine-tuning, which involves modifying only a small subset of the existing parameters, the selection of fine-tuned parameters is task- and domain-specific, making it unsuitable for federated learning. On the other hand, PEFT methods with adding new parameters typically introduce additional inference latency. In this paper, we demonstrate the feasibility of generating a sparse mask in a task-agnostic manner, wherein all downstream tasks share a common mask. Our approach, which relies solely on the magnitude information of pre-trained parameters, surpasses existing methodologies by a significant margin when evaluated on the GLUE benchmark. Additionally, we introduce a novel adapter technique that directly applies the adapter to pre-trained parameters instead of the hidden representation, thereby achieving identical inference speed to that of full fine-tuning. Through extensive experiments, our proposed method attains a new state-of-the-art outcome in terms of both performance and storage efficiency, storing only 0.03% parameters of full fine-tuning.