record performance fixes: FA_ALL_QUANTS build flag (dankserver), RDNA triton FA env (dankclaw)

- frank-default-large: GGML_CUDA_FA_ALL_QUANTS=ON is mandatory in the
  FastMTP build; without it q8_0 KV + FA falls back to a slow path and
  prefill collapses ~12x (95 -> 1312 t/s at 8K, measured)
- frank-default-small: FLASH_ATTENTION_TRITON_AMD_ENABLE=TRUE + pure-python
  flash_attn (triton_amd) + stub; without it the vision encoder warmup
  OOMs via torch SDPA

docs/frank-redo-2026-08-17.md

@@ -72,9 +72,13 @@ Production choice: **131072 (128K)** — the maximum that keeps about
    git checkout 4df29be4f4c3673f428170fda944a5b19f743bb8
    curl -L -o HauhauCS-FastMTP-llama.cpp.patch <HF patch URL>
    git apply HauhauCS-FastMTP-llama.cpp.patch
-   cmake -S . -B build -DGGML_CUDA=ON -DCMAKE_BUILD_TYPE=Release
+   cmake -S . -B build -DGGML_CUDA=ON -DCMAKE_BUILD_TYPE=Release \
+     -DGGML_CUDA_FA=ON -DGGML_CUDA_FA_ALL_QUANTS=ON
    cmake --build build --config Release -j$(nproc)
    ```
+   `GGML_CUDA_FA_ALL_QUANTS=ON` is mandatory. Without it, prefill collapses
+   ~12x (the q8_0 KV + flash attention falls back to a slow path;
+   measured 95 t/s vs 1300+ t/s at 8K on the 3090).
 4. Symlink the unit, reload, enable, restart:
    ```
    sudo ln -sf /home/dank/vLLM/scripts/frank-default-large.service /etc/systemd/system/
@@ -100,13 +104,23 @@ Production choice: **131072 (128K)** — the maximum that keeps about
    ```
    python3 -c "from huggingface_hub import snapshot_download; snapshot_download('Avesed/Qwen3.6-35B-A3B-INT8-W8A8')"
    ```
-4. Symlink the unit, reload, enable, restart:
+4. Install the ROCm wheel set and the flash-attention triton path:
+   ```
+   uv pip install torch --torch-backend=auto
+   uv pip install "vllm==0.27.1+rocm723" --index-url https://wheels.vllm.ai/rocm/ \
+     --extra-index-url https://pypi.org/simple --index-strategy unsafe-best-match --no-build-isolation
+   cp -r <ciru-venv>/site-packages/flash_attn* <vllm-venv>/site-packages/
+   # add a flash_attn_2_cuda stub module (ROCm build has no compiled .so)
+   ```
+   Set `FLASH_ATTENTION_TRITON_AMD_ENABLE=TRUE` (env file). Without it the
+   vision encoder falls back to torch SDPA and engine init OOMs.
+5. Symlink the unit, reload, enable, restart:
    ```
    sudo ln -sf /home/dank/vllmScripts/scripts/frank-default-small.service /etc/systemd/system/
    sudo systemctl daemon-reload && sudo systemctl enable frank-default-small
    sudo systemctl restart frank-default-small
    ```
-5. Verify: `curl -sf http://127.0.0.1:52625/health` and a chat completion.
+6. Verify: `curl -sf http://127.0.0.1:52625/health` and a chat completion.
 
 ## Fallback: vLLM source build for gfx1151