Papers › Pre-training Large Memory Language Models with Internal and External Knowledge

Pre-training Large Memory Language Models with Internal and External Knowledge

21 May 2025arXiv:2505.15962archive 2025-07-28

Linxi Zhao, Sofian Zalouk, Christian K. Belardi, Justin Lovelace, Jin Peng Zhou, Kilian Q. Weinberger, Yoav Artzi, Jennifer J. Sun

Neural language models are black-boxes -- both linguistic patterns and factual knowledge are distributed across billions of opaque parameters. This entangled encoding makes it difficult to reliably inspect, verify, or update specific facts. We propose a new class of language models, Large Memory Language Models (LMLM) with a pre-training recipe that stores factual knowledge in both internal weights and an external database. Our approach strategically masks externally retrieved factual values from the training loss, thereby teaching the model to perform targeted lookups rather than relying on memorization in model weights. Our experiments demonstrate that LMLMs achieve competitive performance compared to significantly larger, knowledge-dense LLMs on standard benchmarks, while offering the advantages of explicit, editable, and verifiable knowledge bases. This work represents a fundamental shift in how language models interact with and manage factual knowledge.

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add_shared_context_ids kilian-group/lmlm/src/lmlm/annotate/utils.py official repository unverified MIT (permissive) · 95803855c12113ac · report
chunk_wiki_text kilian-group/lmlm/src/lmlm/annotate/utils.py official repository unverified MIT (permissive) · a26579611bac7338 · report
extract_database kilian-group/lmlm/src/lmlm/database/database_manager.py official repository unverified MIT (permissive) · 802c4b89ef2911cc · report
extract_lookups kilian-group/lmlm/src/lmlm/database/database_manager.py official repository unverified MIT (permissive) · 1c4a4ce0a56f09bb · report
load_and_filter_dataset kilian-group/lmlm/src/lmlm/database/extract_database.py official repository unverified MIT (permissive) · 4dce5964827c7959 · report
register_dataset kilian-group/lmlm/src/lmlm/annotate/dataloader.py official repository unverified MIT (permissive) · a5fa7fed5e977268 · report
truncate_sample_length kilian-group/lmlm/src/lmlm/annotate/utils.py official repository unverified MIT (permissive) · 0dd1a961e4577e50 · report
update_atomic_knowledge kilian-group/lmlm/src/lmlm/database/database_manager.py official repository unverified MIT (permissive) · ef77276b20d6ebaf · report

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