EvolMem: A Cognitive-Driven Benchmark for Multi-Session Dialogue Memory

AuthorsYe Shen, Dun Pei, Yiqiu Guo et al.

arXiv 20262026

TL;DR

EvolMem uses a hybrid dialogue synthesis framework grounded in cognitive memory types to show that Gemini-3-Pro reaches 67.47% overall memory performance while no LLM dominates all seven abilities.

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THE PROBLEM

Multi session benchmarks miss non declarative memory and realistic dialogue evolution

Existing long context benchmarks mostly test single turn recall and declarative memory, neglecting non declarative systems that support habits and implicit knowledge.

This leaves LLMs and agent memory systems under evaluated on multi session dialogue tasks, where missing habits and learning harms long term coherence, user preference retention, and procedural adaptation.

HOW IT WORKS

EvolMem hybrid dialogue synthesis framework

EvolMem centers on Topic-Initiated Generation, Narrative-Inspired Transformation, Filtering, and Challenge Injection to synthesize multi session dialogues aligned with seven cognitive memory abilities.

Think of EvolMem as a lab where long texts are sliced like chapters, then re staged into conversations, while a curator injects conflicts and removes easy cases.

This KEY_MECHANISM lets EvolMem stress memory evolution, non declarative learning, and habituation in ways a plain context window or static long text benchmark cannot.

DIAGRAM

Memory ability taxonomy in EvolMem

This diagram shows how EvolMem organizes cognitive memory into declarative and non declarative types with seven fine grained abilities.

DIAGRAM

EvolMem evaluation pipeline across metrics

This diagram shows how EvolMem evaluates model answers using result oriented, process oriented, and open ended metrics.

PROCESS

How EvolMem Handles a Multi session dialogue

  1. 01

    Topic Initiated Generation

    EvolMem uses Topic-Initiated Generation with seed task categories and topics to call fLLM under RPLA, producing structured dialogue overviews with sessions, turns, final query, reference answer, and evaluation checklist.

  2. 02

    Narrative Inspired Transformation

    EvolMem applies Narrative-Inspired Transformation to long text benchmarks like Variable Tracking in Ruler, segmenting paragraphs into sessions and turns, then generating human like agent responses via fLLM under RNIT.

  3. 03

    Filtering

    EvolMem runs DeepSeek-V3.2 through its evaluation pipeline on generated dialogues and filters out all samples with scores greater than or equal to 0.8, retaining only challenging and discriminative memory cases.

  4. 04

    Challenge Injection

    EvolMem performs Challenge Injection by inserting plausible but antithetical information and integrating high difficulty benchmarks, forcing models to handle non linear reasoning, conflicts, and long range dependencies.

KEY CONTRIBUTIONS

Key Contributions

  • 01

    Cognitive driven memory benchmark

    EvolMem formalizes memory into declarative and non declarative types with seven abilities including Retrieval, Summarization, Isolation, Inference, Reproduction, Learning, and Habituation, enabling fine grained evaluation.

  • 02

    Multi source data synthesis framework

    EvolMem introduces Topic-Initiated Generation and Narrative-Inspired Transformation plus Filtering and Challenge Injection to build 1,600 multi session dialogues averaging 6.82 sessions and 29.49 turns.

  • 03

    Systematic evaluation of LLMs and agents

    EvolMem shows Gemini-3-Pro reaches 67.47% overall memory performance while MemoryOS, Mem0, HippoRAG, and A-MEM all fail to surpass their DeepSeek-V3.2 base, revealing weaknesses in non declarative memory and efficiency.

RESULTS

By the Numbers

Overall memory

67.47%

+14.94 over Llama-4-Maverick

Habituation ability

84.16%

+69.37 over GPT-5.1

Retrieval ability

58.37%

-22.74 vs Mistral-Large

Agent speed Mem0

30.17s

baseline vs A-MEM at 492.60s

These numbers come from EvolMem’s main LLM and agent tables, which test seven memory abilities over 1,600 multi session dialogues. The results show EvolMem can separate strengths like Gemini-3-Pro’s 84.16% habituation from weaknesses such as GPT-5.1’s 14.79% habituation and A-MEM’s 16.3× latency over Mem0.

BENCHMARK

By the Numbers

These numbers come from EvolMem’s main LLM and agent tables, which test seven memory abilities over 1,600 multi session dialogues. The results show EvolMem can separate strengths like Gemini-3-Pro’s 84.16% habituation from weaknesses such as GPT-5.1’s 14.79% habituation and A-MEM’s 16.3× latency over Mem0.

BENCHMARK

LLM overall memory performance on EvolMem

Overall averaged memory score across declarative and non declarative abilities.

KEY INSIGHT

The Counterintuitive Finding

EvolMem reveals that MemoryOS, Mem0, HippoRAG, and A-MEM all score below their DeepSeek-V3.2 base, with MemoryOS at 48.66% overall versus 52.18%.

This is surprising because agent memory mechanisms are designed to enhance long term reasoning, yet EvolMem shows they can reduce effectiveness while adding latency, challenging assumptions about agentic memory benefits.

WHY IT MATTERS

What this unlocks for the field

EvolMem unlocks a way to stress test LLMs and agents on realistic multi session memory, including non declarative learning and habituation that prior benchmarks ignored.

Builders can now diagnose specific memory weaknesses, tune agent memory mechanisms, and track evolving performance as sessions and difficulty increase, rather than relying on static long context scores.

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