NuoNuo: Hippocampal memory module prototype

Hopfield + Hebbian hybrid memory system for LLMs.
Two nights of experiments (16 iterations), validated on LongMemEval (ICLR 2025).

Architecture:
- Single-hop: Two-Stage Hopfield (NN top-20 → softmax settle)
- Multi-hop: Hebbian W matrix with WTA pattern separation
- 64% on LongMemEval (500 questions), retrieval-only, no LLM dependency
- 4ms latency @ 20K memories, ~1GB VRAM

Key findings:
- Hopfield attention solved noise tolerance (20% → 100% vs flat Hebbian)
- WTA pattern separation enables 20K+ capacity
- Multi-hop associative chains (6 hops, CosSim=1.0) — RAG can't do this
- MiniLM-L6 is optimal (discrimination gap > absolute similarity)
- Paraphrase cue augmentation: 55% → 100% on synthetic, 36% → 64% on benchmark
- SNN encoder viable (CosSim 0.99) but not needed for current architecture

doc/p6_multiturn.md

@@ -0,0 +1,46 @@
+# P6: 多轮对话验证
+
+## 场景
+
+3 天的对话（DB troubleshooting → deployment → monitoring），12 条记忆 + heuristic paraphrase augmentation。
+
+## 跨会话召回：12/12 (100%)
+
+| 查询 | 跨天? | 结果 |
+|------|-------|------|
+| DB is slow again | Day 1 | ✓ "missing index on created_at" |
+| How big is the users table? | Day 1 | ✓ "2.3 million rows" |
+| Who can access the database? | Day 1 | ✓ "Alice, Bob, Charlie" |
+| What Postgres version? | Day 1 | ✓ "PostgreSQL 15.2" |
+| How to deploy? | Day 2 | ✓ "blue-green via GitHub Actions" |
+| How to rollback? | Day 2 | ✓ "switch load balancer" |
+| Who approves deploys? | Day 2 | ✓ "Alice or David" |
+| Monitoring dashboard? | Day 3 | ✓ "grafana.internal" |
+| What alerts? | Day 3 | ✓ "PagerDuty" |
+| DB slow, what index? | Cross | ✓ "created_at" |
+| Deploy logs? | Cross | ✓ "Loki" |
+| Database monitoring exporter | Cross | ✓ "pg_exporter" |
+
+全部 similarity=1.0。Hopfield + augmentation 在小规模（12 memories）下完美。
+
+## Multi-hop
+
+"database is slow" → hop1: "missing index" → hop2: "missing index" → hop3: "2.3 million rows"
+
+hop2 循环了（指回自己），因为 Hebbian W 里 "missing index" 的最强关联还是它自己（自身的 outer product 贡献最大）。需要在 multi-hop 中加**去重**：已访问的 memory 不参与下一跳。
+
+## Memory 冲突
+
+存了两个版本的 PostgreSQL 版本（15.2 和 16.1）：
+- Top-1: "Upgraded to 16.1" (sim=1.0) ← 更新的版本排第一
+- Top-2: "version 15.2" (sim=0.0) ← 旧版本也返回了
+
+当前行为可接受（都返回，新的排前面）。更好的做法：
+- 检测到同 cue 的更新 → 自动替换旧记忆
+- 或标记旧记忆为 "superseded"
+
+## 待改进
+
+1. **Multi-hop 去重**: 已访问的 memory 排除出下一跳候选
+2. **Memory update 检测**: 同 cue 新值自动覆盖旧值
+3. **大规模验证**: 12 条是小规模，需要 100+ 条跨 session 的测试