Overcoming the Quadratic Memory Bottleneck
Standard Transformer attention scales quadratically ($O(N^2)$) with context length. Selective State Space Models (SSMs), exemplified by Mamba-2 and State Space Duality (SSD), offer linear scaling ($O(N)$) for ultra-long context inference.
1. State Space Duality (SSD) Formulation
Mamba-2 unifies continuous state space models with structured matrix multiplications, allowing fast GPU tensor-core execution identical to FlashAttention while retaining continuous-time state compression.
2. Constant Memory Inference
While Transformers accumulate massive Key-Value (KV) cache footprints during token generation, SSMs maintain a fixed hidden state size regardless of generation step, drastically reducing memory overhead during multi-turn chats.
3. Hybrid SSM-Attention Architectures
Production models increasingly combine 80% SSM layers with 20% standard attention layers, capturing global associative recall while preserving linear throughput on document-scale queries.