JigSawPT/DeepSeek-V4.1-Flash-DSpark-GGUF

DeepSeek-V4.1-Flash DSpark draft head, GGUF

The speculative-decoding draft head that ships inside DeepSeek-V4.1-Flash under the mtp.* tensors, exported as a standalone DFLASH-architecture GGUF for llama.cpp: three full V4.1 blocks (128 routed experts, 3 used), the Markov bigram head (rank 256), the confidence head, block size 5. 78 tensors, 7.97 GB.

It runs only on the dsv41-porte branch of JigSawPT/llama.cpp, with the target model from JigSawPT/DeepSeek-V4.1-Flash-GGUF. Upstream llama.cpp has no runtime for V4.1 yet.

What it does for throughput, measured

On an RTX 5090 (31.8 GiB of VRAM) with the target streaming its experts from NVMe, the head is neutral on mixed content: our benchmark (four prompts, three rounds, same day, same configuration) gives 4.92 tokens/s with the draft against 5.13 without, and 21.23 against 21.40 on resident content. Acceptance is high and tracks the content (51 % on Portuguese prose, 79 % on code, 97 % on verbatim repetition), but a verification step pays for the union of experts of its K + 1 tokens, and on a disk-bound machine that cost eats the accepted tokens. Only verbatim repetition gains (+12–15 %). The best draft length on this machine is 2, not the trained block of 5.

In a compute-bound regime, where a batched verification is nearly free, the same acceptance would multiply throughput; that regime needs the working set on the card.

Full numbers and method: the report.

Run

llama-server -m DeepSeek-V4.1-Flash-MXFP4-engram-00001-of-00011.gguf -ngl 99 -c 8192 ^
  --moe-stream --moe-stream-cache 18 --moe-stream-l2 72 --reasoning off ^
  -md DeepSeek-V4.1-Flash-DSpark.gguf --spec-type draft-dspark --spec-draft-n-max 2 -ngld 99 --spec-draft-n-cpu-moe 3

--spec-draft-n-cpu-moe 3 keeps the draft's experts in RAM so the target keeps its VRAM cache; putting them on the card changes nothing and costs the target 5 GiB.

How it was made

python convert_hf_to_gguf.py <DeepSeek-V4.1-Flash> --dspark --target-model-dir <DeepSeek-V4.1-Flash> --outtype bf16 --outfile DeepSeek-V4.1-Flash-DSpark.gguf

The converter class is DeepseekV41DSparkModel. It writes the V4.1 head names (markov_head.embed/head), the draft's own expert counts, the target layers as the reference reads them (the mean over the hyper-connection streams is taken before running layers 37–39), and a dflash.dsv41_semantics key that tells the loader to apply the V4.1 rules: no per-head q norm, the hyper-connection mix threaded one sub-layer ahead, and a final collapse with the last FFN mix (the V4.1 head has no hc_head weights). Draft experts are MXFP4 as released; attention and dense weights Q8_0/BF16 from fp8.

SHA-256 in SHA256SUMS.txt.

Credits

DeepSeek for the model (MIT). Engineering assisted by Claude (Anthropic).