Files
Model-Optimizer/examples/llm_ptq/example_utils.py
T
Chenjie Luo d541324e84 Disable QKV NVFP4 quantization for Qwen3 MOE (#735)
## What does this PR do?

**Type of change:** ? Recipe improvement

**Overview:** ?

Disable QKV NVFP4 quantization for Qwen3 MOE models following the Qwen3
Next recipe for accuracy recovery

## Testing
Model accuracy benchmarking

Signed-off-by: Chenjie Luo <chenjiel@nvidia.com>
2026-01-02 11:06:25 -08:00

560 lines
21 KiB
Python
Executable File

# SPDX-FileCopyrightText: Copyright (c) 2024 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
# SPDX-License-Identifier: Apache-2.0
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import copy
import glob
import os
import shutil
import sys
import warnings
from pathlib import Path
from typing import Any
import torch
import transformers
from accelerate import infer_auto_device_map, init_empty_weights
from accelerate.utils import get_max_memory
from transformers import (
AutoConfig,
AutoModelForCausalLM,
AutoProcessor,
AutoTokenizer,
PreTrainedTokenizerBase,
ProcessorMixin,
)
try:
from huggingface_hub import snapshot_download
except ImportError:
snapshot_download = None
import modelopt.torch.quantization as mtq
from modelopt.torch.utils.image_processor import BaseImageProcessor, MllamaImageProcessor
SPECULATIVE_MODEL_LIST = ["Eagle", "Medusa"]
def run_nemotron_vl_preview(
full_model, tokenizer, input_ids, pyt_ckpt_path, stage_name, allow_fallback=False
):
"""Run text-only and VL preview generation for Nemotron VL models.
Args:
full_model: The full VL model
tokenizer: The tokenizer
input_ids: Input tensor for generation
pyt_ckpt_path: Path to the model checkpoint
stage_name: Description of the stage (e.g., "before quantization", "after quantization")
allow_fallback: Whether to allow fallback to standard generate on failure
Returns:
Generated text response or None if generation failed
"""
from vlm_utils import run_text_only_generation, run_vl_preview_generation
print(f"Running text-only preview generation for Nemotron VL model ({stage_name})...")
question = tokenizer.decode(input_ids[0], skip_special_tokens=True)
generation_config = {
"max_new_tokens": 100,
"do_sample": False,
"eos_token_id": tokenizer.eos_token_id,
}
# Try text-only generation
text_response = run_text_only_generation(
full_model, tokenizer, question, generation_config, pyt_ckpt_path
)
if text_response is not None:
print(f"✅ Text-only generation successful: {text_response[:100]}...")
generated_ids = text_response
elif allow_fallback:
print("Text-only generation failed, falling back to standard generate...")
generated_ids = full_model.generate(input_ids, max_new_tokens=100)
else:
generated_ids = None
# Run additional VL test with images
print(f"Running additional VL test with images ({stage_name})...")
run_vl_preview_generation(full_model, tokenizer, pyt_ckpt_path, stage_name)
return generated_ids
def _is_multimodal_config(config):
"""Check if a config indicates a multimodal model (config-only version of is_multimodal_model)."""
return (
hasattr(config, "vision_config") # Standard vision config (e.g., Qwen2.5-VL)
or getattr(config, "model_type", "") == "phi4mm" # Phi-4 multimodal
or hasattr(config, "vision_lora") # Vision LoRA configurations
or hasattr(config, "audio_processor") # Audio processing capabilities
or (
hasattr(config, "embd_layer") and hasattr(config.embd_layer, "image_embd_layer")
) # Image embedding layers
)
def is_nemotron_vl(model_or_config):
"""Check if model or config indicates a Nemotron VL model.
Args:
model_or_config: Either a model instance or a config object.
Returns:
bool: True if it's a Nemotron VL model, False otherwise.
"""
# Try to get config from model, or use directly if it's a config
if hasattr(model_or_config, "config"):
config = model_or_config.config
from modelopt.torch.export.model_utils import is_multimodal_model
if not is_multimodal_model(model_or_config):
return False
else:
config = model_or_config
if not _is_multimodal_config(config):
return False
architectures = getattr(config, "architectures", [])
return any("nemotron" in arch.lower() for arch in architectures)
def build_quant_cfg(
qformat,
kv_cache_qformat,
awq_block_size,
model_type,
quant_cfg_choices,
kv_quant_cfg_choices,
) -> dict[str, Any]:
quant_cfg = {}
assert qformat in quant_cfg_choices, (
f"Unsupported quantization format: {qformat} with {kv_cache_qformat} KV cache"
)
quant_cfg = quant_cfg_choices[qformat]
if "awq" in qformat:
quant_cfg = copy.deepcopy(quant_cfg_choices[qformat])
weight_quantizer = quant_cfg["quant_cfg"]["*weight_quantizer"]
if isinstance(weight_quantizer, list):
weight_quantizer = weight_quantizer[0]
# If awq_block_size argument is provided, update weight_quantizer
if awq_block_size:
weight_quantizer["block_sizes"][-1] = awq_block_size
# Coarser optimal scale search seems to resolve the overflow in TRT-LLM for some models
if qformat == "w4a8_awq" and model_type in ["gemma", "mpt"]:
quant_cfg["algorithm"] = {"method": "awq_lite", "alpha_step": 1}
enable_quant_kv_cache = kv_cache_qformat != "none"
print(f"{'Enable' if enable_quant_kv_cache else 'Disable'} KV cache quantization")
# Check if any bmm_quantizer is in the quant_cfg. If so, we need to enable the bmm_quantizer.
if enable_quant_kv_cache:
quant_cfg = mtq.update_quant_cfg_with_kv_cache_quant(
quant_cfg,
getattr(mtq, kv_quant_cfg_choices[kv_cache_qformat])["quant_cfg"],
)
# Gemma 7B has accuracy regression using alpha 1. We set 0.5 instead.
if model_type == "gemma" and "int8_sq" in qformat:
quant_cfg["algorithm"] = {"method": "smoothquant", "alpha": 0.5}
if model_type == "phi4mm":
# Only quantize the language model
quant_cfg["quant_cfg"]["*speech*"] = {"enable": False}
quant_cfg["quant_cfg"]["*audio*"] = {"enable": False}
quant_cfg["quant_cfg"]["*image*"] = {"enable": False}
quant_cfg["quant_cfg"]["*vision*"] = {"enable": False}
if model_type in ["qwen3moe", "qwen3next"] and qformat == "nvfp4":
# Disable the attention projection layers to retain accuracy
quant_cfg["quant_cfg"]["model*.*attn*in_proj*"] = {"enable": False}
quant_cfg["quant_cfg"]["model*.*attn*q_proj*"] = {"enable": False}
quant_cfg["quant_cfg"]["model*.*attn*k_proj*"] = {"enable": False}
quant_cfg["quant_cfg"]["model*.*attn*v_proj*"] = {"enable": False}
return quant_cfg
def is_speculative(hf_config):
"""Check if the model architecture is a speculative model."""
return hf_config.architectures and any(
name in hf_config.architectures[0] for name in SPECULATIVE_MODEL_LIST
)
def get_tokenizer(ckpt_path, trust_remote_code=False, **kwargs) -> PreTrainedTokenizerBase:
print(f"Initializing tokenizer from {ckpt_path}")
if "vila" in ckpt_path.lower():
ckpt_path += "/llm"
tokenizer = AutoTokenizer.from_pretrained(
ckpt_path, trust_remote_code=trust_remote_code, **kwargs
)
# can't set attribute 'pad_token' for "<unk>"
# We skip this step for Nemo models
if tokenizer.pad_token != "<unk>" or tokenizer.pad_token is None:
tokenizer.pad_token = tokenizer.eos_token
assert tokenizer.pad_token is not None, f"Pad token for {ckpt_path} cannot be set!"
return tokenizer
def get_processor(
ckpt_path,
model_type,
device: torch.device = "auto",
trust_remote_code=False,
attn_implementation=None,
) -> BaseImageProcessor | ProcessorMixin | None:
"""
Returns a :class:`modelopt.torch.utils.image_processor.MllamaImageProcessor` object.
"""
model_kwargs = {"trust_remote_code": trust_remote_code}
if attn_implementation is not None:
model_kwargs["attn_implementation"] = attn_implementation
if model_type == "whisper":
processor = AutoProcessor.from_pretrained(
ckpt_path,
padding_side="left",
**model_kwargs,
)
if processor.tokenizer.pad_token is None:
processor.tokenizer.pad_token = processor.tokenizer.eos_token
assert processor.tokenizer.pad_token is not None, (
f"Pad token for {ckpt_path} cannot be set!"
)
return processor
elif model_type == "mllama":
processor = AutoProcessor.from_pretrained(
ckpt_path,
padding_side="left",
**model_kwargs,
)
if processor.tokenizer.pad_token is None:
processor.tokenizer.pad_token = processor.tokenizer.eos_token
assert processor.tokenizer.pad_token is not None, (
f"Pad token for {ckpt_path} cannot be set!"
)
return MllamaImageProcessor(processor, device)
return None
def get_dtype(dtype):
if dtype == "bf16":
dtype = torch.bfloat16
elif dtype == "fp16":
dtype = torch.float16
elif dtype == "fp32":
dtype = torch.float32
else:
raise NotImplementedError(f"Unknown dtype {dtype}")
return dtype
def get_model(
ckpt_path,
device="cuda",
gpu_mem_percentage=0.8,
trust_remote_code=False,
use_seq_device_map=False,
attn_implementation=None,
):
print(f"Initializing model from {ckpt_path}")
device_map = "auto"
if device == "cpu":
device_map = "cpu"
# Add VILA to sys.path before loading config if needed
if "vila" in ckpt_path.lower():
vila_path = os.path.join(ckpt_path, "..", "VILA")
if vila_path not in sys.path:
sys.path.append(vila_path)
from llava.model import LlavaLlamaConfig, LlavaLlamaModel # noqa: F401
# Prepare config kwargs for loading
config_kwargs = {"trust_remote_code": trust_remote_code} if trust_remote_code else {}
# Load config once and handle VL model detection
try:
hf_config = AutoConfig.from_pretrained(ckpt_path, **config_kwargs)
if is_nemotron_vl(hf_config):
print(
"Detected Nemotron VL model from config. "
"Disabling automatic device mapping for compatibility."
)
device_map = None
except Exception as e:
print(f"Error: Could not load config from {ckpt_path}: {e}")
raise RuntimeError(f"Failed to load model configuration from {ckpt_path}") from e
if attn_implementation is not None:
config_kwargs["attn_implementation"] = attn_implementation
# Note: Forcibly converting the model precision between bf16 and fp16 may introduce accuracy drop
model_kwargs = config_kwargs.copy()
# Don't set torch_dtype for VILA models as they handle it explicitly in their builder
if "vila" not in ckpt_path.lower():
model_kwargs.setdefault("torch_dtype", "auto")
if "vila" in ckpt_path.lower():
from transformers import AutoModel
hf_vila = AutoModel.from_pretrained(
ckpt_path,
device_map=device_map,
**model_kwargs,
)
model = hf_vila.llm
else:
if use_seq_device_map:
device_map = "sequential"
# If we use sequential, set max_memory limit to ensure that the model does not occupy the full GPU
max_memory = get_max_memory()
max_memory = {key: value * gpu_mem_percentage for key, value in max_memory.items()}
model_kwargs["max_memory"] = max_memory
if hf_config.model_type == "bart":
# device_map "auto" and "cuda" triggers error regarding meta tensor from safetensors
device_map = None
if is_speculative(hf_config):
model = AutoModelForCausalLM.from_pretrained(
ckpt_path,
device_map=device_map,
**model_kwargs,
)
else:
architecture = hf_config.architectures[0]
if not hasattr(transformers, architecture):
warnings.warn(
f"Architecture {architecture} not found in transformers: {transformers.__version__}. "
"Falling back to AutoModelForCausalLM."
)
assert trust_remote_code, (
"Please set trust_remote_code to True if you want to use this architecture"
)
auto_model_module = AutoModelForCausalLM
from_config = auto_model_module.from_config
else:
auto_model_module = getattr(transformers, architecture)
from_config = auto_model_module._from_config
with init_empty_weights():
# When computing the device_map, assuming half precision by default,
# unless specified by the hf_config.
torch_dtype = getattr(hf_config, "torch_dtype", torch.float16)
model_kwargs2 = model_kwargs.copy()
if auto_model_module != AutoModelForCausalLM:
model_kwargs2.pop("trust_remote_code", None)
model_kwargs2["torch_dtype"] = torch_dtype
model_kwargs2.pop("max_memory", None)
model = from_config(hf_config, **model_kwargs2)
max_memory = get_max_memory()
inferred_device_map = infer_auto_device_map(model, max_memory=max_memory)
on_cpu = "cpu" in inferred_device_map.values()
if on_cpu:
for _device in max_memory:
if isinstance(_device, int):
max_memory[_device] *= gpu_mem_percentage
print(
"Model does not fit to the GPU mem. "
f"We apply the following memory limit for calibration: \n{max_memory}\n"
"If you hit GPU OOM issue, please adjust `gpu_mem_percentage` or "
"reduce the calibration `batch_size` manually."
)
model_kwargs["max_memory"] = max_memory
model = auto_model_module.from_pretrained(
ckpt_path,
device_map=device_map,
**model_kwargs,
)
model.eval()
# If device_map was disabled (None), manually move model to target device
if device_map is None and device != "cpu":
print(f"Moving model to {device} device...")
model = model.to(device)
if device == "cuda" and not is_model_on_gpu(model):
print("Warning: Some parameters are not on a GPU. Calibration can be slow or hit OOM")
return model
def is_model_on_gpu(model) -> bool:
"""Returns if the model is fully loaded on GPUs."""
return all("cuda" in str(param.device) for param in model.parameters())
def is_enc_dec(model_type) -> bool:
"""Return if the model is a encoder-decoder model."""
return model_type in ["t5", "bart", "whisper"]
def _resolve_model_path(model_name_or_path: str, trust_remote_code: bool = False) -> str:
"""Resolve a model name or path to a local directory path.
If the input is already a local directory, returns it as-is.
If the input is a HuggingFace model ID, attempts to resolve it to the local cache path.
Args:
model_name_or_path: Either a local directory path or HuggingFace model ID
trust_remote_code: Whether to trust remote code when loading the model
Returns:
Local directory path to the model files
"""
# If it's already a local directory, return as-is
if os.path.isdir(model_name_or_path):
return model_name_or_path
# Try to resolve HuggingFace model ID to local cache path
try:
# First try to load the config to trigger caching
config = AutoConfig.from_pretrained(model_name_or_path, trust_remote_code=trust_remote_code)
# The config object should have the local path information
# Try different ways to get the cached path
if hasattr(config, "_name_or_path") and os.path.isdir(config._name_or_path):
return config._name_or_path
# Alternative: use snapshot_download if available
if snapshot_download is not None:
try:
local_path = snapshot_download(
repo_id=model_name_or_path,
allow_patterns=["*.py", "*.json"], # Only download Python files and config
)
return local_path
except Exception as e:
print(f"Warning: Could not download model files using snapshot_download: {e}")
# Fallback: try to find in HuggingFace cache
from transformers.utils import TRANSFORMERS_CACHE
# Look for the model in the cache directory
cache_pattern = os.path.join(TRANSFORMERS_CACHE, "models--*")
cache_dirs = glob.glob(cache_pattern)
# Convert model name to cache directory format
model_cache_name = model_name_or_path.replace("/", "--")
for cache_dir in cache_dirs:
if model_cache_name in cache_dir:
# Look for the snapshots directory
snapshots_dir = os.path.join(cache_dir, "snapshots")
if os.path.exists(snapshots_dir):
# Get the latest snapshot
snapshot_dirs = [
d
for d in os.listdir(snapshots_dir)
if os.path.isdir(os.path.join(snapshots_dir, d))
]
if snapshot_dirs:
latest_snapshot = max(snapshot_dirs) # Use lexicographically latest
snapshot_path = os.path.join(snapshots_dir, latest_snapshot)
return snapshot_path
except Exception as e:
print(f"Warning: Could not resolve model path for {model_name_or_path}: {e}")
# If all else fails, return the original path
# This will cause the copy function to skip with a warning
return model_name_or_path
def copy_custom_model_files(source_path: str, export_path: str, trust_remote_code: bool = False):
"""Copy custom model files (configuration_*.py, modeling_*.py, *.json, etc.) from source to export directory.
This function copies custom Python files and JSON configuration files that are needed for
models with custom code. It excludes config.json and model.safetensors.index.json as these
are typically handled separately by the model export process.
Args:
source_path: Path to the original model directory or HuggingFace model ID
export_path: Path to the exported model directory
trust_remote_code: Whether trust_remote_code was used (only copy files if True)
"""
if not trust_remote_code:
return
# Resolve the source path (handles both local paths and HF model IDs)
resolved_source_path = _resolve_model_path(source_path, trust_remote_code)
source_dir = Path(resolved_source_path)
export_dir = Path(export_path)
if not source_dir.exists():
if resolved_source_path != source_path:
print(
f"Warning: Could not find local cache for HuggingFace model '{source_path}' "
f"(resolved to '{resolved_source_path}')"
)
else:
print(f"Warning: Source directory '{source_path}' does not exist")
return
if not export_dir.exists():
print(f"Warning: Export directory {export_path} does not exist")
return
# Common patterns for custom model files that need to be copied
custom_file_patterns = [
"configuration_*.py",
"modeling*.py",
"tokenization_*.py",
"processing_*.py",
"image_processing*.py",
"feature_extraction_*.py",
"*.json",
]
copied_files = []
for pattern in custom_file_patterns:
for file_path in source_dir.glob(pattern):
if file_path.is_file():
# Skip config.json and model.safetensors.index.json as they're handled separately
if file_path.name in ["config.json", "model.safetensors.index.json"]:
continue
dest_path = export_dir / file_path.name
try:
shutil.copy2(file_path, dest_path)
copied_files.append(file_path.name)
print(f"Copied custom model file: {file_path.name}")
except Exception as e:
print(f"Warning: Failed to copy {file_path.name}: {e}")
if copied_files:
print(f"Successfully copied {len(copied_files)} custom model files to {export_path}")
else:
print("No custom model files found to copy")