kvcache-ai-ktransformers/kt-kernel/python/__init__.py
mrhaoxx f36699affd feat(sft): AMX MoE SFT backend with LoRA support
Complete SFT (Supervised Fine-Tuning) backend for MoE models using AMX SIMD:

Core C++ implementation:
- sft_moe.hpp: Forward/backward with LoRA fused operations (~5500 lines)
- moe-sft-tp.hpp: Tensor-parallel wrapper for multi-NUMA
- amx/moe-sft-tp.hpp: AMX-specific TP implementation
- avx_kernels.hpp: AVX512 SIMD kernels for LoRA GEMM
- amx_kernels.hpp: AMX tile kernels for Panel5 rank-outer optimization
- worker_pool: RDTSC profiling, Chrome trace output, SFT timer infrastructure
- ext_bindings.cpp: SFT MOE pybind bindings (BF16/INT8/INT4 + SkipLoRA variants)

Python sft/ submodule (kt_kernel.sft):
- base.py: BaseSFTMoEWrapper with buffer management (template method pattern)
- amx.py: AMXSFTMoEWrapper (weight loading, C++ task construction)
- autograd.py: KTMoEFunction (torch.autograd.Function for distributed training)
- layer.py: KTMoELayerWrapper (nn.Module replacing HF MoE layers)
- arch.py: MOEArchConfig (Qwen3/DeepSeek/Mixtral architecture detection)
- weights.py: Expert weight extraction and checkpoint loading
- lora.py: PEFT LoRA adaptation (view buffers, grad buffers, save/load adapter)
- wrapper.py: wrap_moe_layers_with_kt_wrapper, load_kt_model, build_kt_device_map
- config.py: KTConfig dataclass (DeepSpeed-style opaque config passthrough)
- dist_utils.py: Distributed gather/scatter, checkpoint-phase detection

Design decisions:
- Rank-0-only expert pattern: only rank 0 holds C++ wrapper and expert weights
- DeepSpeed-style integration: accelerate keeps only KTransformersPlugin (framework
  interaction fields), all logic in kt_kernel.sft
- Inference isolation: importing kt_kernel does not load sft/ submodule
- Old field name compatibility: _get_kt_config() converts kt_xxx→xxx automatically

Verified: Qwen3-235B-A22B 4GPU AMXBF16 training, loss converges normally.
2026-04-08 23:11:00 +08:00

94 lines
3.2 KiB
Python

# KT-Kernel: High-performance kernel operations for KTransformers
# SPDX-License-Identifier: Apache-2.0
"""
KT-Kernel provides high-performance kernel operations for KTransformers,
including CPU-optimized MoE inference with AMX, AVX, and KML support.
The package automatically detects your CPU capabilities and loads the optimal
kernel variant (AMX, AVX512, or AVX2) at runtime.
Example usage:
>>> from kt_kernel import KTMoEWrapper
>>> wrapper = KTMoEWrapper(
... layer_idx=0,
... num_experts=8,
... num_experts_per_tok=2,
... hidden_size=4096,
... moe_intermediate_size=14336,
... num_gpu_experts=2,
... cpuinfer_threads=32,
... threadpool_count=2,
... weight_path="/path/to/weights",
... chunked_prefill_size=512,
... method="AMXINT4"
... )
Check which CPU variant is loaded:
>>> import kt_kernel
>>> print(kt_kernel.__cpu_variant__) # 'amx', 'avx512', or 'avx2'
Environment Variables:
KT_KERNEL_CPU_VARIANT: Override automatic detection ('amx', 'avx512', 'avx2')
KT_KERNEL_DEBUG: Enable debug output ('1' to enable)
"""
from __future__ import annotations
# Detect CPU and load optimal extension variant
from ._cpu_detect import initialize as _initialize_cpu
_kt_kernel_ext, __cpu_variant__ = _initialize_cpu()
# Make the extension module available to other modules in this package
import sys
sys.modules["kt_kernel_ext"] = _kt_kernel_ext
# Also expose kt_kernel_ext as an attribute for backward compatibility
kt_kernel_ext = _kt_kernel_ext
# Import main API
from .experts import KTMoEWrapper
def __getattr__(name):
if name == "AMXSFTMoEWrapper":
try:
from .sft.amx import AMXSFTMoEWrapper
return AMXSFTMoEWrapper
except (ImportError, AttributeError):
return None
raise AttributeError(f"module 'kt_kernel' has no attribute {name!r}")
# Read version from package metadata (preferred) or fallback to project root
try:
# Try to get version from installed package metadata (works in installed environment)
from importlib.metadata import version, PackageNotFoundError
try:
__version__ = version("kt-kernel")
except PackageNotFoundError:
# Package not installed, try to read from source tree version.py
import os
_root_version_file = os.path.join(os.path.dirname(os.path.dirname(os.path.dirname(__file__))), "version.py")
if os.path.exists(_root_version_file):
_version_ns = {}
with open(_root_version_file, "r", encoding="utf-8") as f:
exec(f.read(), _version_ns)
__version__ = _version_ns.get("__version__", "0.4.3")
else:
__version__ = "0.4.3"
except ImportError:
# Python < 3.8, fallback to pkg_resources or hardcoded version
try:
from pkg_resources import get_distribution, DistributionNotFound
try:
__version__ = get_distribution("kt-kernel").version
except DistributionNotFound:
__version__ = "0.4.3"
except ImportError:
__version__ = "0.4.3"
__all__ = ["KTMoEWrapper", "AMXSFTMoEWrapper", "kt_kernel_ext", "__cpu_variant__", "__version__"]