vLLM serves 1M-token GLM-5.3 contexts on 16 H200s with PCP, DCP and Hybrid HiSparse

In an October 23 engineering post, the vLLM team described serving GLM-5.3 (744B) with 1M-token contexts on 16 H200s split across two nodes in a prefill/decode-disaggregated deployment using FP8 KV cache and MTP3 speculative decoding. PCP8 × DCP8 prefill with Hybrid HiSparse decode delivered 1.7–3.2× the per-user interactivity of DP8 prefill at equal throughput, cut median TTFT from 1.5–5.2 s to 0.8–0.9 s, and reached 8,340 logical tok/s/GPU at 29.6 tok/s/user at concurrency 64; it requires vLLM v0.32.0 or later.