vLLM Contributions — Ethan Feng (chfeng-cs)

Focused area: KV Cache Transfer · Scheduler Optimization · HMA

Core repos: vllm-project/vllm

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Contributions

Core Feature

PR	Title	Status	Impact
vllm#42086	[Core][KV Connector] Bounded early prefetch for waiting requests	❌ Closed	~102ms TTFT reduction (benchmark on A10)
vllm#41847	[KV Transfer] Enable HMA by default for connectors that support it	✅ Merged	Reduces user config burden; fixes MultiConnector gap vs PR #42045

Docs

PR	Title	Status	Impact
vllm#42073	[Docs] Fix RLHF example links	✅ Merged	—
vllm#42066	[Docs] Fix OpenAI batch model argument examples	✅ Merged	—

Other

PR	Title	Status	Impact
vllm#44101	[LMCache] fix lookup lock leak when request is aborted before alloc	🔄 Open	—
vllm#44097	[LMCache] fix missing cache_salt in free_lookup_locks call	🔄 Open	—
vllm#42872	[Bugfix][Model Runner v2] Fix MRV2 KV cache kernel block sizing.	❌ Closed	—
vllm#42321	[KV Connector] Implement on_new_request for LMCacheMPConnector	🔄 Open	—
vllm#42214	[Test][Bugfix] Fix mypy error: missing enable_prompt_embeds arg in test_tp_sp_nvfp4_generation	❌ Closed	—
vllm#42206	[Metrics] Add group-aware KV cache capacity Prometheus gauges	🔄 Open	—
vllm#42160	[Docs] Fix broken local links	✅ Merged	—
vllm#42077	[Docs] Update server entrypoint examples	✅ Merged	—

Last synced: 2026-06-02 06:37 UTC

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Background

Brief context on the work: prefill-decode disaggregation requires efficient KV cache transfer between nodes. The PRs above address scheduler-level prefetch scheduling and hybrid KV cache manager (HMA) defaults to reduce latency and simplify configuration.

Related design notes in notes/.