InvokeAI/invokeai/backend/util/devices.py
2024-03-01 10:42:33 +11:00

76 lines
2.5 KiB
Python

from __future__ import annotations
from contextlib import nullcontext
from typing import Union, Optional
import torch
from torch import autocast
from invokeai.app.services.config import InvokeAIAppConfig
CPU_DEVICE = torch.device("cpu")
CUDA_DEVICE = torch.device("cuda")
MPS_DEVICE = torch.device("mps")
config = InvokeAIAppConfig.get_config()
def choose_torch_device() -> torch.device:
"""Convenience routine for guessing which GPU device to run model on"""
if config.use_cpu: # legacy setting - force CPU
return CPU_DEVICE
elif config.device == "auto":
if torch.cuda.is_available():
return torch.device("cuda")
if hasattr(torch.backends, "mps") and torch.backends.mps.is_available():
return torch.device("mps")
else:
return CPU_DEVICE
else:
return torch.device(config.device)
def choose_precision(device: torch.device) -> str:
"""Returns an appropriate precision for the given torch device"""
if device.type == "cuda":
device_name = torch.cuda.get_device_name(device)
if not ("GeForce GTX 1660" in device_name or "GeForce GTX 1650" in device_name):
if config.precision == "bfloat16":
return "bfloat16"
else:
return "float16"
elif device.type == "mps":
return "float16"
return "float32"
def torch_dtype(device: Optional[torch.device] = None) -> torch.dtype:
device = device or choose_torch_device()
precision = choose_precision(device)
if precision == "float16":
return torch.float16
if precision == "bfloat16":
return torch.bfloat16
else:
# "auto", "autocast", "float32"
return torch.float32
def choose_autocast(precision):
"""Returns an autocast context or nullcontext for the given precision string"""
# float16 currently requires autocast to avoid errors like:
# 'expected scalar type Half but found Float'
if precision == "autocast" or precision == "float16":
return autocast
return nullcontext
def normalize_device(device: Union[str, torch.device]) -> torch.device:
"""Ensure device has a device index defined, if appropriate."""
device = torch.device(device)
if device.index is None:
# cuda might be the only torch backend that currently uses the device index?
# I don't see anything like `current_device` for cpu or mps.
if device.type == "cuda":
device = torch.device(device.type, torch.cuda.current_device())
return device