SABER: Switchable and Balanced Training for Efficient LLM Reasoning

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Zhao, Kai, Zhao, Yanjun, Song, Jiaming, He, Shien, Zhang, Lusheng, Zhang, Qiang, Li, Tianjiao
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912537192169472
author Zhao, Kai
Zhao, Yanjun
Song, Jiaming
He, Shien
Zhang, Lusheng
Zhang, Qiang
Li, Tianjiao
author_facet Zhao, Kai
Zhao, Yanjun
Song, Jiaming
He, Shien
Zhang, Lusheng
Zhang, Qiang
Li, Tianjiao
contents Large language models (LLMs) empowered by chain-of-thought reasoning have achieved impressive accuracy on complex tasks but suffer from excessive inference costs and latency when applied uniformly to all problems. We propose SABER (Switchable and Balanced Training for Efficient LLM Reasoning), a reinforcement learning framework that endows LLMs with user-controllable, token-budgeted reasoning. SABER first profiles each training example's base-model thinking token usage and assigns it to one of the predefined budget tiers. During fine-tuning, the model is guided by system prompts and length-aware rewards to respect its assigned budget. In parallel, we incorporate no-think examples to ensure the model remains reliable even when explicit reasoning is turned off. SABER further supports four discrete inference modes - NoThink, FastThink, CoreThink, and DeepThink, enabling flexible trade-offs between latency and reasoning depth. Extensive evaluations on math reasoning (MATH, GSM8K), code generation (MBPP), and logical reasoning (LiveBench-Reasoning) demonstrate that SABER achieves high accuracy under tight budgets, graceful degradation, and effective cross-scale and cross-domain generalization. In particular, SABER-FastThink cuts reasoning length by 65.4% and yields a 3.6% accuracy gain compared with the base model on the MATH benchmark.
format Preprint
id arxiv_https___arxiv_org_abs_2508_10026
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle SABER: Switchable and Balanced Training for Efficient LLM Reasoning
Zhao, Kai
Zhao, Yanjun
Song, Jiaming
He, Shien
Zhang, Lusheng
Zhang, Qiang
Li, Tianjiao
Computation and Language
Artificial Intelligence
Machine Learning
Large language models (LLMs) empowered by chain-of-thought reasoning have achieved impressive accuracy on complex tasks but suffer from excessive inference costs and latency when applied uniformly to all problems. We propose SABER (Switchable and Balanced Training for Efficient LLM Reasoning), a reinforcement learning framework that endows LLMs with user-controllable, token-budgeted reasoning. SABER first profiles each training example's base-model thinking token usage and assigns it to one of the predefined budget tiers. During fine-tuning, the model is guided by system prompts and length-aware rewards to respect its assigned budget. In parallel, we incorporate no-think examples to ensure the model remains reliable even when explicit reasoning is turned off. SABER further supports four discrete inference modes - NoThink, FastThink, CoreThink, and DeepThink, enabling flexible trade-offs between latency and reasoning depth. Extensive evaluations on math reasoning (MATH, GSM8K), code generation (MBPP), and logical reasoning (LiveBench-Reasoning) demonstrate that SABER achieves high accuracy under tight budgets, graceful degradation, and effective cross-scale and cross-domain generalization. In particular, SABER-FastThink cuts reasoning length by 65.4% and yields a 3.6% accuracy gain compared with the base model on the MATH benchmark.
title SABER: Switchable and Balanced Training for Efficient LLM Reasoning
topic Computation and Language
Artificial Intelligence
Machine Learning
url https://arxiv.org/abs/2508.10026