Commit Graph

6 Commits

Author SHA1 Message Date
450793311c Wire CuTeDSL kernels into vLLM: replace all BF16 dequant with native NVFP4
- CuTeDSLNvfp4Method: custom quant method that creates CuTeDSL runners
  during process_weights_after_loading, then swaps to CuTeDSLNvfp4LinearMethod
  for forward dispatch
- Attention projections (fused_wqa_wkv, wq_b, wo_b) now route through
  CuTeDSLNvfp4Linear (cosine 0.992-0.996 vs BF16 reference)
- Shared expert now uses CuTeDSLSharedExpertRunner (cosine 0.992 vs BF16)
  with monkey-patched forward for fused L1+SiLU+L2 pipeline
- Deleted all BF16 dequant code (_dequant_nvfp4_to_bf16, _post_quant_fix,
  input_scale fixes)
- Deleted _post_quant_fix hook from utils.py
- Fixed SwiGLU clamp: gate clamped BEFORE SiLU (matching SiluAndMulWithClamp)
- Cleaned up all debug prints
- Updated Dockerfile with new kernel files
2026-05-18 20:27:42 +00:00
82ac648563 Patch utils.py the standard way: copy modified file into Docker image
Instead of fragile inline Dockerfile patching, just copy a modified
utils.py (with _post_quant_fix call) into the image, same pattern
as deepseek_v4.py and deepseek_v4_attention.py patches.
2026-05-18 19:10:08 +00:00
3c1a76bdcc Fix Dockerfile: use external patch script instead of inline Python
Docker's parser chokes on multi-line Python in RUN. Moved to
scripts/patch_utils.py and COPY + RUN it.
2026-05-18 19:03:57 +00:00
75844a8361 Post-quant fix via Dockerfile patch to process_weights_after_loading
Forward pre-hook approach didn't work — torch.compile and model
wrappers bypass hooks. Instead, patch vLLM's utils.py to call
model._post_quant_fix() at the end of process_weights_after_loading.
This guarantees the fix runs AFTER quant methods set up their attrs.

Dockerfile now patches:
  model_loader/utils.py → calls model._post_quant_fix() if it exists

DeepseekV4ForCausalLM._post_quant_fix() dequantizes attention
NVFP4 weights to BF16 and replaces quant_method.
2026-05-18 18:35:34 +00:00
b04bff7e8b feat: clean Dockerfile, docker-compose, import fixes for CuTeDSL build
Dockerfile:
- Removed: C++ CUTLASS extension build, TileLang install, CUTLASS clone
- Added: nvidia-cutlass-dsl==4.5.0 install, cutedsl/ copy
- Copy nvfp4_cutedsl.py to vllm models dir
- Verify step checks cutlass import

docker-compose.yml:
- Removed stale env vars (MEGA_MOE_DEBUG, MEGA_MOE_STATIC, etc.)

deepseek_v4.py:
- Fix import: vllm.nvfp4_cutedsl → vllm.model_executor.models.nvfp4_cutedsl

README.md:
- Updated results: 0% weight loss confirmed (bit-identical view-cast)
- 1.1% cosine loss is entirely from activation quantization
2026-05-16 03:50:07 +00:00
9908fd64d9 feat: CUTLASS NVFP4 mega_moe kernel — slot-based L1/L2, source-first SF remap
Major changes from initial TileLang prototype:

Kernel:
- CUTLASS NVFP4 block-scaled GEMM (SM100 Blackwell, OpClassBlockScaledTensorOp)
- Slot-based dispatch: L1 GEMM → SiLU+Mul per-slot → L2 GEMM → index_add scatter
- 1D slot_expert_ids passed to both L1 and L2 (no 2D topk_ids rebuild)
- slot_token gathered in cutlass_grouped_nvfp4_gemm when provided

SF Remap (source-first):
- Iterates logical (m, k_sf) source grid, uses layout_sf(make_coord(m, k_sf))
  for CUTLASS dest index — no idx2crd/flatten coordinate extraction
- 2D kernel launch: dim3 block(32,8), grid over (K_sf, MN)
- Uses cute::cosize() for physical allocation size (not cute::size)
- SFA: (MN, K_sf) row-major; SFB: (K_sf, MN) row-major (col-major)

Weight transform:
- UE4M3 unpack with bit reinterpret (not value cast)
- Global scale folding (weight_scale_2) for gate/up split
- clamp(0,448) → float8_e4m3fn, transpose (N,K)→(K,N) for CUTLASS

No prepack cache:
- SFB remapped per-call inside CUTLASS (~µs, not the bottleneck)
- See README for why prepack cache must never return (OOM, CUDA graphs,
  M-dependent layout, cross-layer collisions)

Stage activation:
- Nearest-neighbor E2M1 quantization (no clamp, no uniform steps)
- Per-tensor global scale → alpha for L2 GEMM

Bug fixes:
- _fold_global_scale: removed broken logical_widths branch
- unpack_ue4m3_u32: int32 for CUDA bitwise, view not to, ND support
- Correct expert param mapping for NVFP4 checkpoint
- SiLU applied per-slot (not after summing expert paths)
2026-05-15 11:38:18 +00:00