InvokeAI/invokeai/backend/requantize.py
2024-08-26 20:17:50 -04:00

54 lines
1.8 KiB
Python

from typing import Any, Dict
import torch
from optimum.quanto.quantize import _quantize_submodule
# def custom_freeze(model: torch.nn.Module):
# for name, m in model.named_modules():
# if isinstance(m, QModuleMixin):
# m.weight =
# m.freeze()
def requantize(
model: torch.nn.Module,
state_dict: Dict[str, Any],
quantization_map: Dict[str, Dict[str, str]],
device: torch.device = None,
):
if device is None:
device = next(model.parameters()).device
if device.type == "meta":
device = torch.device("cpu")
# Quantize the model with parameters from the quantization map
for name, m in model.named_modules():
qconfig = quantization_map.get(name, None)
if qconfig is not None:
weights = qconfig["weights"]
if weights == "none":
weights = None
activations = qconfig["activations"]
if activations == "none":
activations = None
_quantize_submodule(model, name, m, weights=weights, activations=activations)
# Move model parameters and buffers to CPU before materializing quantized weights
for name, m in model.named_modules():
def move_tensor(t, device):
if t.device.type == "meta":
return torch.empty_like(t, device=device)
return t.to(device)
for name, param in m.named_parameters(recurse=False):
setattr(m, name, torch.nn.Parameter(move_tensor(param, "cpu")))
for name, param in m.named_buffers(recurse=False):
setattr(m, name, move_tensor(param, "cpu"))
# Freeze model and move to target device
# freeze(model)
# model.to(device)
# Load the quantized model weights
model.load_state_dict(state_dict, strict=False)