A recurrent alternative to attention looked 78.7 percent lighter on VRAM until the attention kernel was fused
AspireAI community · arXiv (Dmytro Babarytskyi, Oleksandr Babarytskyi)
This paper formalizes a Dynamic Wave recurrent layer built on input-dependent exponential damping and cosine phase modulation, then tests Pure Transformer, Pure Wave and a Hybrid Wave-Attention stack of three 10.94M-parameter configurations on TinyStories. The hybrid reached the best perplexity at 5.95 against 6.93 for the Transformer and 7.26 for Pure Wave, and Pure Wave used 78.7 percent less peak VRAM at a 4096-token context against an unfused attention baseline. The catch is the baseline: against a fused scaled-dot-product attention kernel the same comparison yields no advantage at all, and in training mode Pure Wave is 8.3 percent more expensive than the Transformer. Hoisting elementwise terms out of the recurrence loop alone speeds the layer 2.53-fold, and the authors note a hybrid stack tends to inherit the cost of its more expensive mixer rather than the advantage of its cheaper one.
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