# Copyright The Lightning AI team.
#
# 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.
from typing import Any, Union
import torch
from lightning_utilities.core.imports import RequirementCache
from typing_extensions import override
from lightning_fabric.accelerators import _AcceleratorRegistry
from lightning_fabric.accelerators.cpu import _parse_cpu_cores
from lightning_fabric.utilities.types import _DEVICE
from pytorch_lightning.accelerators.accelerator import Accelerator
from pytorch_lightning.utilities.exceptions import MisconfigurationException
class CPUAccelerator(Accelerator):
"""Accelerator for CPU devices."""
@override
def setup_device(self, device: torch.device) -> None:
"""
Raises:
MisconfigurationException:
If the selected device is not CPU.
"""
if device.type != "cpu":
raise MisconfigurationException(f"Device should be CPU, got {device} instead.")
@override
def get_device_stats(self, device: _DEVICE) -> dict[str, Any]:
"""Get CPU stats from ``psutil`` package."""
return get_cpu_stats()
@override
def teardown(self) -> None:
pass
@staticmethod
@override
def parse_devices(devices: Union[int, str]) -> int:
"""Accelerator device parsing logic."""
return _parse_cpu_cores(devices)
@staticmethod
@override
def get_parallel_devices(devices: Union[int, str]) -> list[torch.device]:
"""Gets parallel devices for the Accelerator."""
devices = _parse_cpu_cores(devices)
return [torch.device("cpu")] * devices
@staticmethod
@override
def auto_device_count() -> int:
"""Get the devices when set to auto."""
return 1
@staticmethod
@override
def is_available() -> bool:
"""CPU is always available for execution."""
return True
@classmethod
@override
def register_accelerators(cls, accelerator_registry: _AcceleratorRegistry) -> None:
accelerator_registry.register(
"cpu",
cls,
description=cls.__name__,
)
# CPU device metrics
_CPU_VM_PERCENT = "cpu_vm_percent"
_CPU_PERCENT = "cpu_percent"
_CPU_SWAP_PERCENT = "cpu_swap_percent"
_PSUTIL_AVAILABLE = RequirementCache("psutil")
def get_cpu_stats() -> dict[str, float]:
if not _PSUTIL_AVAILABLE:
raise ModuleNotFoundError(
f"Fetching CPU device stats requires `psutil` to be installed. {str(_PSUTIL_AVAILABLE)}"
)
import psutil
return {
_CPU_VM_PERCENT: psutil.virtual_memory().percent,
_CPU_PERCENT: psutil.cpu_percent(),
_CPU_SWAP_PERCENT: psutil.swap_memory().percent,
}