arXiv Machine Learning By Andreas Kirsch

LSTM-Style Looped Transformers with Shared KV Caches

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The paper introduces an LSTM-style transformer that shares a single key–value cache across its recurrent core, reducing parameters by 40.4% compared to an untied model while keeping forward FLOPs similar. It aligns parallel and continuation training passes with a consistency loss, eliminating 81–89% of the continuation‑loss penalty on FineWeb. Experiments across multiple widths and token budgets show that weight tying incurs the smallest loss cost at lower token budgets, highlighting its potential for data‑ and storage‑constrained settings.

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