Knowledge note
vLLM
vLLM serving framework pages: architecture, PagedAttention, scheduling, prefill/decode disaggregation, context parallelism, and model code readings.
vLLM
The pinned vLLM source record and code reading notes at commit 02aa10539f15c8c73aa7fd4a5ee0f691cbf88dcb retain the October 2026 checkpoint analysis evidence.
- MiMo-V2.6-Pro-MOPD: vLLM Inference and Deployment — Version and memory requirements, H200 TP8 and MI355X TP4 launch profiles, tool parsers, and optional DFlash decoding.
- MiMo-V2.6-Flash-MOPD: vLLM Inference and Deployment — Flash-specific TP4 launch, MXFP4 memory floor, H200 and AMD backend profiles, and optional DFlash configuration.
- vLLM Architecture and Code Organization Overview — Start here: the six-layer mental model, the
vllm/andvllm/v1/directory maps, component-by-component responsibilities, the request lifecycle across processes, and the main extension points. - GLM-5.2 on vLLM: Request-to-GPU Backend Inference Path — Complete upstream request round trip through OpenAI admission, V1 scheduling, the CUDA GPU runner, configuration-driven shared sparse indexers, Hopper/Blackwell sparse-MLA kernels, routed/shared MoE, sampling, detokenization, response emission, and cleanup.
- DeepSeek-V4.1-Flash on NVIDIA vLLM: GPU Inference Path — Worker-boundary trace through model resolution, V4.1 cache/indexer ownership, sparse-MLA backend selection, mHC/MoE, and sampled-token output.
- GLM-5.1 on vLLM: Expert-Parallel MoE Path — Code-backed trace from the shared GLM-5.1 model shell through EP group sizing, global-to-local expert mapping, router dispatch, local expert MLPs, backend combine, and residual return.
- vLLM MHA Code Path: From QKV to Paged KV Cache — Decoder self-attention from tensor-parallel QKV projection and RoPE through per-step metadata, slot-mapped KV writes, paged backend execution, and the output projection.
- vLLM: PagedAttention Serving Framework — LLM serving framework design, PagedAttention KV-cache paging, block tables, copy-on-write sharing, scheduling/preemption, distributed execution, and throughput results.
- vLLM Continuous Batching: Scheduler, KV Blocks, and Runtime Flow — Current V1 iteration loop (continuous batching), token and sequence budgets, running/waiting admission, chunked prefill, paged KV-slot allocation, persistent worker batches, completion, and preemption.
- vLLM Data-Parallel Deployment: Internal and External Load Balancing — Deployment strategy for internal, hybrid, per-rank external, and multi-port external load balancing, including MoE synchronization and launch topologies.
- vLLM Prefill/Decode Disaggregated Deployment Path — Deployment-oriented request trace across the router, prefill pool, NIXL KV-transfer plane, and decode pool, with pull/push modes, independent scaling, compatibility gates, and failure policy.
- vLLM Block Table Management: From PagedAttention to the V1 KV Cache Stack — Deep dive into the V1 block pool, per-group KV cache managers, hash-based prefix caching, refcount/copy-on-write sharing, block recycling, and the worker-side block table tensors consumed by PagedAttention kernels.
- vLLM Mamba2 and Linear-Attention Prefix-Cache Path — How repeated token prefixes become recurrent-state checkpoints, how hybrid cache groups agree on one resume boundary, and how Mamba2/GDN/linear-attention layers reuse the state through shared
MambaSpecplumbing. - vLLM DCP and PCP: Decode and Prefill Context Parallelism — How PCP partitions current-step query rows and restores token order while DCP partitions persistent KV rows and restores exact softmax normalization.
- vLLM DCP Attention: From Local LSE to Exact Global Output — Focused derivation of the DCP attention path, stable LSE correction kernel, exactness proof, and AG+RS versus AG+AR output distribution.
- vLLM Kimi K3 Code Reading Map — Upstream vLLM Kimi K3 implementation map covering XTML request handling, multimodal wrapper, KimiLinear text model, hybrid KDA/MLA attention, latent MoE, DeepGEMM MegaMoE, MTP, and K3-specific kernels.
- MiniMax GQA W4A4 Quantization Path: GPU (vLLM) and NPU (vllm-ascend) — Beginner-oriented W4A4 mental model, layer placement, offline/load/runtime lifecycle, GPU and NPU implementation paths, hardware fallbacks, and pinned code evidence.
Related: vLLM Ascend — the Ascend NPU port of vLLM.