Goto

Collaborating Authors

 loss spike







SoftSignSGD(S3): An Enhanced Optimizer for Practical DNN Training and Loss Spikes Minimization Beyond Adam

Peng, Hanyang, Qin, Shuang, Yu, Yue, Jiang, Fangqing, Wang, Hui, Gao, Wen

arXiv.org Artificial Intelligence

Adam has proven remarkable successful in training deep neural networks, but the mechanisms underlying its empirical successes and limitations remain underexplored. In this study, we demonstrate that the effectiveness of Adam stems largely from its similarity to SignSGD in robustly handling large gradient fluctuations, yet it is also vulnerable to destabilizing loss spikes due to its uncontrolled update scaling. To enhance the advantage of Adam and mitigate its limitation, we propose SignSoftSGD (S3), a novel optimizer with three key innovations. \emph{First}, S3 generalizes the sign-like update by employing a flexible $p$-th order momentum ($p \geq 1$) in the denominator, departing from the conventional second-order momentum (variance) preconditioning. This design enables enhanced performance while achieving stable training even with aggressive learning rates. \emph{Second}, S3 minimizes the occurrences of loss spikes through unified exponential moving average coefficients for numerator and denominator momenta, which inherently bound updates to $[-1, 1]$ and simplify hyperparameter tuning. \emph{Third}, S3 incorporates an equivalent Nesterov's accelerated gradient(NAG) module, accelerating convergence without memory overhead. Theoretically, we prove that S3 achieves the optimal convergence rate of $O\left(\frac{1}{T^{\sfrac{1}{4}}}\right)$ for general nonconvex stochastic optimization under weak assumptions. Extensive experiments across a range of vision and language tasks show that \textsf{\small S3} not only converges more rapidly and improves performance but also rarely experiences loss spikes, even with a \textbf{$\bm{10 \times}$} larger learning rate. In fact, S3 delivers performance comparable to or better than AdamW with \textbf{$2 \times$} the training steps, establishing its efficacy in both efficiency and final task performance.


Adaptive Preconditioners Trigger Loss Spikes in Adam

Bai, Zhiwei, Zhou, Zhangchen, Zhao, Jiajie, Li, Xiaolong, Li, Zhiyu, Xiong, Feiyu, Yang, Hongkang, Zhang, Yaoyu, Xu, Zhi-Qin John

arXiv.org Artificial Intelligence

Loss spikes emerge commonly during training across neural networks of varying architectures and scales when using the Adam optimizer. In this work, we investigate the underlying mechanism responsible for Adam spikes. While previous explanations attribute these phenomena to the lower-loss-as-sharper characteristics of the loss landscape, our analysis reveals that Adam's adaptive preconditioners themselves can trigger spikes. Specifically, we identify a critical regime where squared gradients become substantially smaller than the second-order moment estimates, causing the latter to undergo a $β_2$-exponential decay and to respond sluggishly to current gradient information. This mechanism can push the maximum eigenvalue of the preconditioned Hessian beyond the classical stability threshold $2/η$ for a sustained period, inducing instability. This instability further leads to an alignment between the gradient and the maximum eigendirection, and a loss spike occurs precisely when the gradient-directional curvature exceeds $2/η$. We verify this mechanism through extensive experiments on fully connected networks, convolutional networks, and Transformer architectures.


Every FLOP Counts: Scaling a 300B Mixture-of-Experts LING LLM without Premium GPUs

Ling Team, null, Zeng, Binwei, Huang, Chao, Zhang, Chao, Tian, Changxin, Chen, Cong, Jin, Dingnan, Yu, Feng, Zhu, Feng, Yuan, Feng, Wang, Fakang, Wang, Gangshan, Zhai, Guangyao, Zhang, Haitao, Li, Huizhong, Zhou, Jun, Liu, Jia, Fang, Junpeng, Ou, Junjie, Hu, Jun, Luo, Ji, Zhang, Ji, Liu, Jian, Sha, Jian, Qian, Jianxue, Wu, Jiewei, Zhao, Junping, Li, Jianguo, Feng, Jubao, Di, Jingchao, Xu, Junming, Yao, Jinghua, Xu, Kuan, Du, Kewei, Li, Longfei, Liang, Lei, Yu, Lu, Tang, Li, Ju, Lin, Xu, Peng, Cui, Qing, Liu, Song, Li, Shicheng, Song, Shun, Yan, Song, Cai, Tengwei, Chen, Tianyi, Guo, Ting, Huang, Ting, Feng, Tao, Wu, Tao, Wu, Wei, Zhang, Xiaolu, Yang, Xueming, Zhao, Xin, Hu, Xiaobo, Lin, Xin, Zhao, Yao, Wang, Yilong, Guo, Yongzhen, Wang, Yuanyuan, Yang, Yue, Cao, Yang, Fu, Yuhao, Xiong, Yi, Li, Yanzhe, Li, Zhe, Zhang, Zhiqiang, Liu, Ziqi, Huan, Zhaoxin, Wen, Zujie, Sun, Zhenhang, Du, Zhuoxuan, He, Zhengyu

arXiv.org Artificial Intelligence

In this technical report, we tackle the challenges of training large-scale Mixture of Experts (MoE) models, focusing on overcoming cost inefficiency and resource limitations prevalent in such systems. To address these issues, we present two differently sized MoE large language models (LLMs), namely Ling-Lite and Ling-Plus (referred to as "Bailing" in Chinese, spelled B\v{a}il\'ing in Pinyin). Ling-Lite contains 16.8 billion parameters with 2.75 billion activated parameters, while Ling-Plus boasts 290 billion parameters with 28.8 billion activated parameters. Both models exhibit comparable performance to leading industry benchmarks. This report offers actionable insights to improve the efficiency and accessibility of AI development in resource-constrained settings, promoting more scalable and sustainable technologies. Specifically, to reduce training costs for large-scale MoE models, we propose innovative methods for (1) optimization of model architecture and training processes, (2) refinement of training anomaly handling, and (3) enhancement of model evaluation efficiency. Additionally, leveraging high-quality data generated from knowledge graphs, our models demonstrate superior capabilities in tool use compared to other models. Ultimately, our experimental findings demonstrate that a 300B MoE LLM can be effectively trained on lower-performance devices while achieving comparable performance to models of a similar scale, including dense and MoE models. Compared to high-performance devices, utilizing a lower-specification hardware system during the pre-training phase demonstrates significant cost savings, reducing computing costs by approximately 20%. The models can be accessed at https://huggingface.co/inclusionAI.


Stable-SPAM: How to Train in 4-Bit More Stably than 16-Bit Adam

Huang, Tianjin, Hu, Haotian, Zhang, Zhenyu, Jin, Gaojie, Li, Xiang, Shen, Li, Chen, Tianlong, Liu, Lu, Wen, Qingsong, Wang, Zhangyang, Liu, Shiwei

arXiv.org Artificial Intelligence

This paper comprehensively evaluates several recently proposed optimizers for 4-bit training, revealing that low-bit precision amplifies sensitivity to learning rates and often causes unstable gradient norms, leading to divergence at higher learning rates. Among these, SPAM, a recent optimizer featuring momentum reset and spike-aware gradient clipping, achieves the best performance across various bit levels, but struggles to stabilize gradient norms, requiring careful learning rate tuning. To address these limitations, we propose Stable-SPAM, which incorporates enhanced gradient normalization and clipping techniques. In particular, Stable-SPAM (1) adaptively updates the clipping threshold for spiked gradients by tracking their historical maxima; (2) normalizes the entire gradient matrix based on its historical $l_2$-norm statistics; and $(3)$ inherits momentum reset from SPAM to periodically reset the first and second moments of Adam, mitigating the accumulation of spiked gradients. Extensive experiments show that Stable-SPAM effectively stabilizes gradient norms in 4-bit LLM training, delivering superior performance compared to Adam and SPAM. Notably, our 4-bit LLaMA-1B model trained with Stable-SPAM outperforms the BF16 LLaMA-1B trained with Adam by up to $2$ perplexity. Furthermore, when both models are trained in 4-bit, Stable-SPAM achieves the same loss as Adam while requiring only about half the training steps. Code is available at https://github.com/TianjinYellow/StableSPAM.git.


Understanding Silent Data Corruption in LLM Training

Ma, Jeffrey, Pei, Hengzhi, Lausen, Leonard, Karypis, George

arXiv.org Artificial Intelligence

As the scale of training large language models (LLMs) increases, one emergent failure is silent data corruption (SDC), where hardware produces incorrect computations without explicit failure signals. In this work, we are the first to investigate the impact of real-world SDCs on LLM training by comparing model training between healthy production nodes and unhealthy nodes exhibiting SDCs. With the help from a cloud computing platform, we access the unhealthy nodes that were swept out from production by automated fleet management. Using deterministic execution via XLA compiler and our proposed synchronization mechanisms, we isolate and analyze the impact of SDC errors on these nodes at three levels: at each submodule computation, at a single optimizer step, and at a training period. Our results reveal that the impact of SDCs on computation varies on different unhealthy nodes. Although in most cases the perturbations from SDCs on submodule computation and gradients are relatively small, SDCs can lead models to converge to different optima with different weights and even cause spikes in the training loss. Our analysis sheds light on further understanding and mitigating the impact of SDCs.