Beyond Static Dialogues: Benchmarking Realistic, Heterogeneous, and Evolving Long-Horizon Memory

Han Zhang, Zihao Tang, Xin Yu, Xiao Liu, Yeyun Gong, Haizhen Huang, Yan Lu, Weiwei Deng, Feng Sun, Qi Zhang, Hanfang Yang


Abstract
In existing memory benchmarks for Large Language Models (LLMs), the evaluated dialogue sessions often lack long-term semantic consistency, and the underlying personas tend to be flat and static. Furthermore, in real-world scenarios, interactions between users and assistants involve more diverse, heterogeneous data streams, such as documents and emails. These shortcomings significantly limit the realism and effectiveness of current evaluations. To address these limitations, we introduce RHELM ( ̲Realistic,  ̲Heterogeneous, and  ̲Evolving  ̲Long-term  ̲Memory). Driven by meticulously crafted user profiles and a novel LOOP (p ̲Lan-r ̲Ollout-ev ̲Olve- ̲Prune) module, we construct realistic dialogues across diverse interaction scenarios that exhibit dynamic temporal evolution and long-term coherence. Crucially, these dialogues are deeply integrated with heterogeneous external sources synchronized with the user’s temporal event trajectory. The resulting benchmark encompasses challenging question-answer pairs spanning seven inquiry types, with each question mapping to at least one of 27 critical memory characteristics that we identify as essential yet underexplored in current research. Comprehensive experiments across full-context models, retrieval-augmented generation (RAG) methods, and representative memory frameworks reveal that contemporary approaches still expose critical weaknesses in complex, real-world settings, particularly in resolving multi-source aggregation and real-world contextual reasoning.
Anthology ID:
2026.findings-emnlp.1679
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2026
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
Findings
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
35836–35872
Language:
URL:
https://aclanthology.org/2026.findings-emnlp.1679/
DOI:
Bibkey:
Cite (ACL):
Han Zhang, Zihao Tang, Xin Yu, Xiao Liu, Yeyun Gong, Haizhen Huang, Yan Lu, Weiwei Deng, Feng Sun, Qi Zhang, and Hanfang Yang. 2026. Beyond Static Dialogues: Benchmarking Realistic, Heterogeneous, and Evolving Long-Horizon Memory. In Findings of the Association for Computational Linguistics: EMNLP 2026, pages 35836–35872, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
Beyond Static Dialogues: Benchmarking Realistic, Heterogeneous, and Evolving Long-Horizon Memory (Zhang et al., Findings 2026)
Copy Citation:
PDF:
https://aclanthology.org/2026.findings-emnlp.1679.pdf