Inference
Perplexity's Mac Engine Reads 24x Faster Than It Writes
Perplexity turned on hybrid compute in its Mac app on 1 September, then open sourced Lily, the engine underneath it, on 2 September. Lily averages 4,156 prefill tokens per second and 170 decode tokens per second on an M5 Max. That 24x gap is the real design constraint, and it explains exactly which half of the work Perplexity kept on the device.
Marco Kotrotsos·4 Sep 2026·7 min read
