AMMA replaces GPU compute dies with memory-centric chiplets for 1M-token attention, reporting 15.5x lower latency than an H100
AspireAI community · arXiv (cs.AI, cs.LG)
Current LLM serving puts the GPU at the centre even though decode-phase attention is memory-bound, and the mismatch gets worse as reasoning and agentic workloads push context toward one million tokens. AMMA is a multi-chiplet, memory-centric architecture that replaces GPU compute dies with HBM-PNM cubes to roughly double available memory bandwidth, adds a logic-die microarchitecture that exploits per-cube internal bandwidth for decode attention, a two-level hybrid parallelism scheme, and a reordered collective flow that cuts die-to-die communication. The paper also reports a design-space exploration over per-cube compute power and intra-chip link bandwidth. Evaluations show 15.5 times lower attention latency and 6.9 times lower energy consumption compared with the NVIDIA H100. This is a simulation-based hardware study against one GPU generation, not a shipping product, and it was accepted to MICRO 2026.
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