Add HiSparse MLA decode#46326
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In mixed host/device KV registration, _build_fa_local stamps every xfer
descriptor with the local GPU device_id, but host-resident MLA regions are
registered under CPU device_id 0. prep_xfer_dlist("DRAM", ...) then raised
NIXL_ERR_NOT_FOUND on every TP rank whose GPU index != 0, breaking HiSparse +
NIXL for TP>1 (and the MultiConnector NIXL+Mooncake llm-d path). Force DRAM
xfer descriptors to device_id 0 to match their registration.
Teach the Mooncake shared-store offload path to save/load HiSparse's mixed host-resident MLA KV (pinned DRAM) and GPU indexer KV (VRAM): - ChunkedTokenDatabase carries per-segment memory kind (host/device), defaulting to the flat all-device behavior for non-HiSparse models. - MooncakeStoreWorker.register_kv_caches detects CPU(pinned)/GPU tensors, registers both, and records their memory kinds. A block's value spans the host MLA + device indexer segments; Mooncake's Transfer Engine resolves each registered buffer's device, so the mixed list moves in one multi-buffer op. - Reject enable_cross_layers_blocks under HiSparse (host MLA + device indexer can't share one packed cross-layer tensor). - Recognize MooncakeStoreConnector/MultiConnector as validated HiSparse connectors, and document that the post-receive hot-row reset is connector-agnostic. Adds focused unit tests for segment metadata, mixed host/device registration, save/load address generation, the cross-layer guard, and the recv admission signal.
Relax the PD-decode (kv_consumer) requirement so HiSparse works on any deployment. The decode hot-buffer (swap_in) and prefill host-staging (_hisparse_host_prefill_cache / write_rows_to_host) paths already branch per-batch on is_hisparse_decode_batch (not on PD), and host-resident allocation/sizing are gated on enable_hisparse, so only two guards tied HiSparse to PD: - create_hisparse_coordinator no longer requires a kv_consumer connector. - VllmConfig validation now warns (instead of raising) when there is no consumer connector, noting that a unified instance's prefill gathers KV from host memory (slower than a normal GPU prefill; PD decode-only avoids this). PD decode-only remains the intended fast path. Updates the corresponding unit test to confirm the coordinator builds without a connector.
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supported_models.mdandexamplesfor a new model.