integration: validate GLM-5.2 sparse CKV stack on latest GG

[FujitsuPolycom]

Purpose

Fork-only integration gate for the GLM-5.2 sparse CKV stack, rebased onto
local-inference-lab/vllm dev/gilded-gnosis at b07bef75b6.

No upstream PR is authorized by this integration PR.

What is included

• mixed replicated-indexer + DCP-sharded main CKV allocation
• replicated target sparse-indexer cache
• depth-N native full-CKV prefetch
• selected-record sparse CKV decode with per-sequence MTP union/dedup
• C1-C8 pooled sparse workspaces and fallback
• bulk S1/S2/S3 copy-engine prefetch
• target/draft and model-lane state isolation
• native 432-byte BF16-RoPE and compact 368-byte FP8-RoPE CKV records
• calibrated per-layer NVFP4 MLA outer-scale wiring

The companion transport implementation is
FujitsuPolycom/sparkinfer#4.

Design

GLM-5.2 Sparse CKV under Decode Context Parallelism
documents the architecture, feature gates, fallbacks, correctness invariants,
and proposed upstream decomposition.

Final validated profile

• ai01: ASUS WRX90E-SAGE SE, Threadripper PRO 9965WX, 128 GiB RAM
• 4x RTX PRO 6000 Blackwell 96 GiB at 400 W
• TP4 / DCP4 / MTP3
• max model length 300,000; reported KV capacity 304,863 tokens
• max batched tokens 4,096; graph 32; max sequences 8
• nvfp4_ds_mla, KV_FP8_ROPE=1, native 368-byte records
• calibrated per-layer MLA outer scales
• replicated indexer, depth-3 full CKV prefetch, bulk S1/S2/S3
• selected-record sparse decode over CE; NCCL TP all-reduce; no LMCache

Cold prefill

Prompt	tok/s
8K	3,404
64K	3,173
128K	2,887
257,634 tokens	2,495
291,822 tokens	2,432

Aggregate decode

Context	C1	C2	C4	C8
32K	89.2	118.2	137.1	164.7
64K	87.5	122.1	136.0	-
128K	91.3	113.2	-	-

Dashes are capacity-limited combinations, not failed fast-path cells.

Temperature-zero coding peak, five runs: 114.0 tok/s median, 113.9 mean,
114.7 max.

Validation

• focused vLLM suite: 110 passed, 1 skipped
• paired Sparkinfer CPU transport suite: 49 passed
• 368-byte direct and CE four-GPU correctness gates: passed
• deterministic replay: byte-identical across repeats
• clean cold-prefill gates completed at 128K, 257,634, and 291,822 tokens
• C1/C2/C4/C8 decode exercised under the final image
• no external requests overlapped the final candidate measurements

Scope and remaining validation

• physically validated on TP4/DCP1-4 and MTP0-3; TP6/TP8/DCP8 remain untested
• FP8-RoPE support preserves the native resident ABI; it does not change model math
• CE and direct transports remain feature-gated with stock fallback
• the long-context bounded-scratch indexer fix lives in the companion Sparkinfer PR

Credits

The design is primarily based on Koush's sparse-CKV, shared-layer lookahead,
and MTP-deduplication work, with Luke Alonso's B12X/Sparkinfer infrastructure.
Implementation, testing, benchmarking, and documentation were developed with
OpenAI Codex assistance and validated on the target host.

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[FujitsuPolycom]

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