_version_ 1866915923332431872
author Cai, Aichen
Zhang, Anmeng
Li, Anyu
Zhang, Bo
Cai, Bohua
Li, Chang
Jiang, Changjian
Lu, Changkai
Xue, Chao
Liang, Chaocai
Zhang, Cheng
Liu, Dongkai
Wang, Fei
Huang, Guoqiang
Ke, Haijian
Lin, Han
Wang, Hao
Miao, Ji
Zhang, Jiacheng
Shi, Jialong
Zhu, Jifeng
Qian, Jingjing
Luo, Junhui
Xiong, Junwu
So, Lam
Huang, Liang
Ke, Ming
Li, Mingyang
Shi, Panfeng
Hao, Peng
Wang, Qi
Lai, Qian
Yuan, Qiaoqiao
Yin, Qingyu
Cao, Qiong
Wang, Qixiang
Bian, Rongcheng
Han, Rongduo
Zheng, Shaoqiang
Hu, Shi
Suo, Shi
Ren, Shijie
Zhang, Shijin
Fan, Shiying
Xie, Shuai
Zhang, Tianyi
Liu, Wei
Tan, Wentao
Meng, Xianghan
He, Xiaodong
Pan, Xing
Wang, Xiran
Peng, Xuyang
Zhang, Ya
Liu, Yang
Duan, Yangyang
Chen, Yanxu
Gong, Yicheng
Huang, Yidan
Liu, Yifei
Bai, Yinhao
Liu, Yongqiang
Zhang, Yuesong
Zhang, Yuqi
Xie, Zerui
Wang, Zhenfang
Shen, Zhennan
Liu, Zheyuan
Zeng, Zhuwei
author_facet Cai, Aichen
Zhang, Anmeng
Li, Anyu
Zhang, Bo
Cai, Bohua
Li, Chang
Jiang, Changjian
Lu, Changkai
Xue, Chao
Liang, Chaocai
Zhang, Cheng
Liu, Dongkai
Wang, Fei
Huang, Guoqiang
Ke, Haijian
Lin, Han
Wang, Hao
Miao, Ji
Zhang, Jiacheng
Shi, Jialong
Zhu, Jifeng
Qian, Jingjing
Luo, Junhui
Xiong, Junwu
So, Lam
Huang, Liang
Ke, Ming
Li, Mingyang
Shi, Panfeng
Hao, Peng
Wang, Qi
Lai, Qian
Yuan, Qiaoqiao
Yin, Qingyu
Cao, Qiong
Wang, Qixiang
Bian, Rongcheng
Han, Rongduo
Zheng, Shaoqiang
Hu, Shi
Suo, Shi
Ren, Shijie
Zhang, Shijin
Fan, Shiying
Xie, Shuai
Zhang, Tianyi
Liu, Wei
Tan, Wentao
Meng, Xianghan
He, Xiaodong
Pan, Xing
Wang, Xiran
Peng, Xuyang
Zhang, Ya
Liu, Yang
Duan, Yangyang
Chen, Yanxu
Gong, Yicheng
Huang, Yidan
Liu, Yifei
Bai, Yinhao
Liu, Yongqiang
Zhang, Yuesong
Zhang, Yuqi
Xie, Zerui
Wang, Zhenfang
Shen, Zhennan
Liu, Zheyuan
Zeng, Zhuwei
contents We introduce JoyAI-LLM Flash, an efficient Mixture-of-Experts (MoE) language model designed to redefine the trade-off between strong performance and token efficiency in the sub-50B parameter regime. JoyAI-LLM Flash is pretrained on a massive corpus of 20 trillion tokens and further optimized through a rigorous post-training pipeline, including supervised fine-tuning (SFT), Direct Preference Optimization (DPO), and large-scale reinforcement learning (RL) across diverse environments. To improve token efficiency, JoyAI-LLM Flash strategically balances \emph{thinking} and \emph{non-thinking} cognitive modes and introduces FiberPO, a novel RL algorithm inspired by fibration theory that decomposes trust-region maintenance into global and local components, providing unified multi-scale stability control for LLM policy optimization. To enhance architectural sparsity, the model comprises 48B total parameters while activating only 2.7B parameters per forward pass, achieving a substantially higher sparsity ratio than contemporary industry leading models of comparable scale. To further improve inference throughput, we adopt a joint training-inference co-design that incorporates dense Multi-Token Prediction (MTP) and Quantization-Aware Training (QAT). We release the checkpoints for both JoyAI-LLM-48B-A3B Base and its post-trained variants on Hugging Face to support the open-source community.
format Preprint
id arxiv_https___arxiv_org_abs_2604_03044
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle JoyAI-LLM Flash: Advancing Mid-Scale LLMs with Token Efficiency
Cai, Aichen
Zhang, Anmeng
Li, Anyu
Zhang, Bo
Cai, Bohua
Li, Chang
Jiang, Changjian
Lu, Changkai
Xue, Chao
Liang, Chaocai
Zhang, Cheng
Liu, Dongkai
Wang, Fei
Huang, Guoqiang
Ke, Haijian
Lin, Han
Wang, Hao
Miao, Ji
Zhang, Jiacheng
Shi, Jialong
Zhu, Jifeng
Qian, Jingjing
Luo, Junhui
Xiong, Junwu
So, Lam
Huang, Liang
Ke, Ming
Li, Mingyang
Shi, Panfeng
Hao, Peng
Wang, Qi
Lai, Qian
Yuan, Qiaoqiao
Yin, Qingyu
Cao, Qiong
Wang, Qixiang
Bian, Rongcheng
Han, Rongduo
Zheng, Shaoqiang
Hu, Shi
Suo, Shi
Ren, Shijie
Zhang, Shijin
Fan, Shiying
Xie, Shuai
Zhang, Tianyi
Liu, Wei
Tan, Wentao
Meng, Xianghan
He, Xiaodong
Pan, Xing
Wang, Xiran
Peng, Xuyang
Zhang, Ya
Liu, Yang
Duan, Yangyang
Chen, Yanxu
Gong, Yicheng
Huang, Yidan
Liu, Yifei
Bai, Yinhao
Liu, Yongqiang
Zhang, Yuesong
Zhang, Yuqi
Xie, Zerui
Wang, Zhenfang
Shen, Zhennan
Liu, Zheyuan
Zeng, Zhuwei
Computation and Language
Artificial Intelligence
We introduce JoyAI-LLM Flash, an efficient Mixture-of-Experts (MoE) language model designed to redefine the trade-off between strong performance and token efficiency in the sub-50B parameter regime. JoyAI-LLM Flash is pretrained on a massive corpus of 20 trillion tokens and further optimized through a rigorous post-training pipeline, including supervised fine-tuning (SFT), Direct Preference Optimization (DPO), and large-scale reinforcement learning (RL) across diverse environments. To improve token efficiency, JoyAI-LLM Flash strategically balances \emph{thinking} and \emph{non-thinking} cognitive modes and introduces FiberPO, a novel RL algorithm inspired by fibration theory that decomposes trust-region maintenance into global and local components, providing unified multi-scale stability control for LLM policy optimization. To enhance architectural sparsity, the model comprises 48B total parameters while activating only 2.7B parameters per forward pass, achieving a substantially higher sparsity ratio than contemporary industry leading models of comparable scale. To further improve inference throughput, we adopt a joint training-inference co-design that incorporates dense Multi-Token Prediction (MTP) and Quantization-Aware Training (QAT). We release the checkpoints for both JoyAI-LLM-48B-A3B Base and its post-trained variants on Hugging Face to support the open-source community.
title JoyAI-LLM Flash: Advancing Mid-Scale LLMs with Token Efficiency
topic Computation and Language
Artificial Intelligence
url https://arxiv.org/abs/2604.03044