arXiv Machine Learning

The COUNT: Counting N-grams Unlocks Scaling on Host Memory and Training-Free Adaptation

The paper introduces COUNT, a method that builds n‑gram embeddings without adding learned parameters by storing precomputed n‑gram counts on host memory. By weighting the language model’s own unembeddings with corpus frequencies, COUNT can be added as an extra input embedding during pretraining, improving validation loss equivalent to a 57% increase in compute for a 1B‑parameter model. Additionally, COUNT enables efficient GPU memory usage and allows domain‑specific n‑gram tables to be swapped in at inference time for training‑free adaptation.

arXiv Machine Learning
Aug 27

Ladder Up, Memory Down: Low-Cost Fine-Tuning With Side Nets

The paper introduces Ladder Side Tuning (LST), a parameter‑efficient fine‑tuning method that adds a lightweight side network to large language models. LST matches QLoRA’s compute scaling while halving peak memory usage, enabling 7B‑parameter models to be fine‑tuned on a single 12 GB GPU with 2k‑token contexts without gradient checkpointing. The authors also present xLadder, a depth‑extended variant that increases effective depth through cross‑connections, allowing deeper reasoning without extra memory overhead.

By Estelle Zheng, Nathan Cerisara, S\'ebastien Warichet, Emmanuel Helbert, Christophe Cerisara
arXiv Computation and Language
1d ago

Low-Bit N-Gram Embeddings for Language Models

The paper investigates reducing memory usage of n‑gram embedding tables in open‑weight language models by storing them in low precision. Experiments on nanochat, Llama, and GPT‑2 families show that four‑bit tables cut table memory by about 75% while retaining over 99% of the validation‑loss improvement. The study also demonstrates that re‑allocating the saved memory to larger tables can surpass the performance of full‑precision tables, and that similar savings are achievable in large models like DeepSeek‑V4.1‑Flash and Qwen3.8‑Flash‑Next with minimal impact on perplexity and downstream tasks.

By Stephen Chung, Wenyu Du
arXiv Machine Learning
Aug 4

Structured Recurrent Mixers for Massively Parallelized Sequence Generation

arXiv:2605. 08696v4 Announce Type: replace-cross Abstract: Over the last two decades, language modeling has experienced a shift from the use of predominantly recurrent architectures that process tokens sequentially during training and inference to non-recurrent models that process sequence elements in parallel during training, which results in greater training efficiency and stability at the expense of lower inference throughput.

By Benjamin L. Badger
arXiv AI
Jul 14

Conditional Memory via Scalable Lookup: A New Axis of Sparsity for Large Language Models

arXiv:2601. 07372v2 Announce Type: replace-cross Abstract: While Mixture-of-Experts (MoE) scales capacity via conditional computation, Transformers lack a native primitive for knowledge lookup, forcing them to inefficiently simulate retrieval through computation.

By Xin Cheng, Rui Tian, Wangding Zeng, Damai Dai, Qinyu Chen, Bingxuan Wang, Zhenda Xie, Kezhao Huang, Xingkai Yu, Chengqi Deng, Shangyan Zhou, Chenggang Zhao, Zhewen Hao, Yukun Li, Han Zhang, Zhengyan Zhang, Yixu Wei, M. Y Xu, Huishuai Zhang, Dongyan Zhao, Wenfeng Liang
arXiv AI
5d ago

Activation-Efficient Fine-Tuning via Sequence-Compressed Low-Rank Subspaces

The paper introduces LARS (Low-memory Activation-Rank Subspace), a parameter-efficient fine-tuning method that reduces the memory footprint of adapter activations by operating in a sequence-level low-rank subspace. By replacing token-level activations with pooled feature extraction, low-rank modulations, and residual projection, LARS cuts the stored activation intermediates from O(BSRL) to O(BRL). Experiments show that LARS achieves comparable performance to LoRA while lowering GPU memory usage by 23%, CPU memory usage by 47.8%, and reducing CPU power and energy consumption per optimization step by about 22%.

By Irene Tenison, Stella Ahn, Miriam Kim, Ebtisam Alshehri, Lalana Kagal
arXiv Computation and Language
Sep 4

Lngram v2: Latent N-Gram Memory with Interpretable Discrete Representations

Lngram v2 introduces a latent N‑gram memory system that decouples memory routes, memory dimension, and backbone width, enabling scalable memory capacity for transformers. It employs context‑aware grouped‑query attention, a zero‑value sink, and counterfactual surrogate gradients to improve readout selectivity and routing trainability while preserving hard discrete addressing. Experiments on vision‑language models up to 30B parameters show consistent performance gains, reduced memory parameters, and stable semantic structure in the discrete IDs.

By Yunao Zheng, Bin Wen, Xiaojie Wang
arXiv Machine Learning
Oct 12

STAPLE: Static Sparse Upcycling of Pretrained Checkpoints via Embedding Modules

STAPLE is a method that integrates static sparse memory into pretrained language models by adding token‑indexed embeddings as a residual pathway while preserving the original feed‑forward network. On the OLMo‑2 1B and 7B models, STAPLE outperforms dense training and other static sparse baselines, improving benchmark scores by up to 4.27 points and achieving faster decoding with less GPU memory and energy usage. The approach demonstrates that large pretrained models can be expanded efficiently without costly sparse pretraining from scratch.

By Ranajoy Sadhukhan, Euijin Hong, Sheng Cao, Zechun Liu, Shuowei Jin, Sha Li, Changlong Yu, Xin Liu, Qin Lu, Zhenyu Shi, Priyanka Nigam, Beidi Chen