Dynamic Long Context Reasoning over Compressed Memory via End-to-End Reinforcement Learning

Zhuoen Chen, Dongfang Li, Meishan Zhang, Baotian Hu, Min Zhang


Abstract
Large Language Models (LLMs) face severe challenges in long-context processing, including quadratic computational costs, information forgetting, and the context fragmentation inherent in Retrieval-Augmented Generation (RAG). We introduce LycheeMemory, a cognitively inspired framework that enables efficient long-context inference via chunk-wise compression and selective memory recall, rather than processing all raw tokens. LycheeMemory segments the input into chunks and encodes each into compressed KV-cache style representations using a Compressor. A Gate then dynamically selects relevant memory blocks, which a Reasoner iteratively processes with an evolving working memory to solve downstream tasks. The Compressor and Reasoner are jointly optimized via end-to-end reinforcement learning, while the Gate is trained separately as a classifier. Experimental results demonstrate that LycheeMemory achieves competitive accuracy (up to 82% in ablation variants) on multi-hop reasoning benchmarks (e.g., RULER-HQA), successfully extrapolates context length from 7K to 1.75M, and provides a favorable accuracy–efficiency trade-off against strong long-context baselines. Notably, compared to MemAgent, LycheeMemory achieves an average 2× reduction in peak GPU memory usage and a 6× speedup during inference.
Anthology ID:
2026.acl-long.365
Volume:
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Month:
July
Year:
2026
Address:
San Diego, California, United States
Editors:
Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
Venue:
ACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
8064–8083
Language:
URL:
https://preview.aclanthology.org/ingest-acl/2026.acl-long.365/
DOI:
Bibkey:
Cite (ACL):
Zhuoen Chen, Dongfang Li, Meishan Zhang, Baotian Hu, and Min Zhang. 2026. Dynamic Long Context Reasoning over Compressed Memory via End-to-End Reinforcement Learning. In Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers), pages 8064–8083, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
Dynamic Long Context Reasoning over Compressed Memory via End-to-End Reinforcement Learning (Chen et al., ACL 2026)
Copy Citation:
PDF:
https://preview.aclanthology.org/ingest-acl/2026.acl-long.365.pdf
Checklist:
 2026.acl-long.365.checklist.pdf