76 lines
2.8 KiB
Go
76 lines
2.8 KiB
Go
|
// Copyright 2018-2022 Tobias Klauser
|
||
|
|
//
|
||
|
|
// 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.
|
||
|
|
|
||
|
|
// Package numcpus provides information about the number of CPUs in the system.
|
||
|
|
//
|
||
|
|
// It gets the number of CPUs (online, offline, present, possible or kernel
|
||
|
|
// maximum) on Linux, Darwin, FreeBSD, NetBSD, OpenBSD, DragonflyBSD,
|
||
|
|
// Solaris/Illumos or Windows systems.
|
||
|
|
//
|
||
|
|
// On Linux, the information is retrieved by reading the corresponding CPU
|
||
|
|
// topology files in /sys/devices/system/cpu.
|
||
|
|
//
|
||
|
|
// On BSD systems, the information is retrieved using the hw.ncpu and
|
||
|
|
// hw.ncpuonline sysctls, if supported.
|
||
|
|
//
|
||
|
|
// On Windows systems, the information is retrieved using the
|
||
|
|
// GetActiveProcessorCount and GetMaximumProcessorCount functions, respectively.
|
||
|
|
//
|
||
|
|
// Not all functions are supported on Darwin, FreeBSD, NetBSD, OpenBSD,
|
||
|
|
// DragonflyBSD, Solaris/Illumos and Windows. ErrNotSupported is returned in
|
||
|
|
// case a function is not supported on a particular platform.
|
||
|
|
package numcpus
|
||
|
|
|
||
|
|
import "errors"
|
||
|
|
|
||
|
|
// ErrNotSupported is the error returned when the function is not supported.
|
||
|
|
var ErrNotSupported = errors.New("function not supported")
|
||
|
|
|
||
|
|
// GetConfigured returns the number of CPUs configured on the system. This
|
||
|
|
// function should return the same value as `getconf _SC_NPROCESSORS_CONF` on a
|
||
|
|
// unix system.
|
||
|
|
func GetConfigured() (int, error) {
|
||
|
|
return getConfigured()
|
||
|
|
}
|
||
|
|
|
||
|
|
// GetKernelMax returns the maximum number of CPUs allowed by the kernel
|
||
|
|
// configuration. This function is only supported on Linux and Windows systems.
|
||
|
|
func GetKernelMax() (int, error) {
|
||
|
|
return getKernelMax()
|
||
|
|
}
|
||
|
|
|
||
|
|
// GetOffline returns the number of offline CPUs, i.e. CPUs that are not online
|
||
|
|
// because they have been hotplugged off or exceed the limit of CPUs allowed by
|
||
|
|
// the kernel configuration (see GetKernelMax). This function is only supported
|
||
|
|
// on Linux systems.
|
||
|
|
func GetOffline() (int, error) {
|
||
|
|
return getOffline()
|
||
|
|
}
|
||
|
|
|
||
|
|
// GetOnline returns the number of CPUs that are online and being scheduled.
|
||
|
|
func GetOnline() (int, error) {
|
||
|
|
return getOnline()
|
||
|
|
}
|
||
|
|
|
||
|
|
// GetPossible returns the number of possible CPUs, i.e. CPUs that
|
||
|
|
// have been allocated resources and can be brought online if they are present.
|
||
|
|
func GetPossible() (int, error) {
|
||
|
|
return getPossible()
|
||
|
|
}
|
||
|
|
|
||
|
|
// GetPresent returns the number of CPUs present in the system.
|
||
|
|
func GetPresent() (int, error) {
|
||
|
|
return getPresent()
|
||
|
|
}
|