GLM-5.3 320B (18B active) Flash

User benchmarks GLM-5.3-Flash-MLX-mixed-4_8bit on an M5 Ultra 256GB with oMLX, reporting 61.7 t/s generation and 1587.5 t/s prompt processing at 1024-token prompt. Setup uses MLX mixed 4/8-bit weights with peak MLX memory of 174.17 GB; a 131k context prefill would need ~208.28 GB, exceeding the 205.80 GB prefill limit. At longer prompts generation stays 58.1-59.6 t/s and prefill 2323.9-2373.0 t/s; continuous batching reaches 67.3 t/s at 2x and 99.3 t/s at 4x.