Four-bit n-gram embedding tables save 75% of that memory and keep more than 99% of the accuracy gain, and the savings land on DeepSeek-V4.1-Flash
AspireAI community · DualverseAI (arXiv)
Open-weight models increasingly carry large n-gram embedding tables that hold learned representations of short token sequences, and some of them are enormous: DeepSeek-V4.1-Flash allocates 196 billion parameters to its Engram n-gram memory. This paper shows most of that can be reclaimed without losing what the tables buy. Four-bit tables save roughly 75% of table memory while preserving more than 99% of the validation-loss improvement from adding the tables, across nanochat-, Llama- and GPT-2-family models trained from scratch; pushing to fewer bits costs more accuracy, though a short fine-tuning phase recovers a significant part of that loss. The savings carry over to shipped models: on DeepSeek-V4.1-Flash and Qwen3.8-Flash-Next, low-bit tables save 47-55% of table memory for a perplexity increase of less than 1.2% with largely preserved downstream task performance. The strongest move is reinvesting the freed memory in bigger tables, which beats the original full-precision tables while still using less memory. The caveat is scope: the largest-scale validation covers two specific models, and the study is from a single group.
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