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Rename MTP GGUFs
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# Gemma 4 31B QAT MTP drafter
Multi-Token Prediction (MTP) drafter for `unsloth/gemma-4-31B-it-qat-GGUF`. It runs as a speculative draft model that shares the target's KV cache and speeds up text generation. The drafter is the Gemma 4 31B QAT assistant and pairs with the QAT model unchanged.
Verified on a single B200 against the `gemma-4-31B-it-qat-UD-Q4_K_XL.gguf` target with `-hf` auto-discovery: draft acceptance 0.79.
MTP was merged into llama.cpp on 2026-06-07 (PR ggml-org/llama.cpp#23398). You need a llama.cpp build from after that date. Older builds cannot load these (arch `gemma4-assistant`).
## Files
The recommended drafter is a **smart Q4_0**: the native 4-bit QAT drafter (about 97% of its weights are byte-exact on the int4 grid), near-lossless versus higher precision while roughly half the size. It sits at the repo root as `mtp-gemma-4-31B-it.gguf` so `-hf` finds it automatically, and the same file plus higher-precision drafters are in `MTP/`:
- `mtp-gemma-4-31B-it.gguf` (repo root, smart Q4_0, recommended; used by `-hf`)
- `MTP/mtp-gemma-4-31B-it-Q4_0.gguf` (same smart Q4_0)
- `MTP/mtp-gemma-4-31B-it-Q8_0.gguf`
- `MTP/mtp-gemma-4-31B-it-BF16.gguf`
- `MTP/mtp-gemma-4-31B-it-F16.gguf`
## Build llama.cpp
```bash
git clone https://github.com/ggml-org/llama.cpp
cd llama.cpp
# CUDA build. Set the arch for your GPU: 89 (RTX 4090), 90 (H100), 100 (B200).
cmake -B build -DGGML_CUDA=ON -DCMAKE_CUDA_ARCHITECTURES=90
cmake --build build --config Release -j --target llama-server
```
## Run, the easy way
A recent llama.cpp finds the drafter automatically from the root `mtp-` file, so `-hf` is all you need. No `--model-draft`.
```bash
./build/bin/llama-server \
-hf unsloth/gemma-4-31B-it-qat-GGUF:UD-Q4_K_XL \
--spec-type draft-mtp --spec-draft-n-max 4 \
-ngl 999 -fa on
```
If your build is too old to auto-discover the sibling, use the explicit form below.
## Run with an explicit drafter
Use this to choose a precision or point at a local file.
```bash
hf download unsloth/gemma-4-31B-it-qat-GGUF gemma-4-31B-it-qat-UD-Q4_K_XL.gguf --local-dir .
hf download unsloth/gemma-4-31B-it-qat-GGUF MTP/mtp-gemma-4-31B-it-Q8_0.gguf --local-dir .
./build/bin/llama-server \
-m gemma-4-31B-it-qat-UD-Q4_K_XL.gguf \
--model-draft MTP/mtp-gemma-4-31B-it-Q8_0.gguf \
--spec-type draft-mtp --spec-draft-n-max 4 \
-ngl 999 -fa on
```
Multi GPU: add `--spec-draft-device CUDA0 -sm layer`. The drafter pairs with any quant of the 31B QAT model. Quantized KV cache works.