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2021手机能看的网站西安未央区今天出啥事了

news 2025/9/17 12:11:48

2021手机能看的网站,西安未央区今天出啥事了,机械网站建设案例,合肥营销型网站建设automaxprocs能够自动调整Go程序中的Goroutine数量，以充分利用系统资源并提高程序的性能。 automaxprocs通过读取系统信息，如CPU核心数和Cgroups限制，来动态调整Goroutine的数量 automaxprocs获取CPU限额的关键方法在 // CPUQuotaToGOMAXP…

automaxprocs能够自动调整Go程序中的Goroutine数量，以充分利用系统资源并提高程序的性能。

automaxprocs通过读取系统信息，如CPU核心数和Cgroups限制，来动态调整Goroutine的数量

automaxprocs获取CPU限额的关键方法在

// CPUQuotaToGOMAXPROCS converts the CPU quota applied to the calling process
// to a valid GOMAXPROCS value. The quota is converted from float to int using round.
// If round == nil, DefaultRoundFunc is used.
func CPUQuotaToGOMAXPROCS(minValue int, round func(v float64) int) (int, CPUQuotaStatus, error) {if round == nil {round = DefaultRoundFunc}cgroups, err := _newQueryer()if err != nil {return -1, CPUQuotaUndefined, err}quota, defined, err := cgroups.CPUQuota()if !defined || err != nil {return -1, CPUQuotaUndefined, err}maxProcs := round(quota)if minValue > 0 && maxProcs < minValue {return minValue, CPUQuotaMinUsed, nil}return maxProcs, CPUQuotaUsed, nil
}

可以看到是先获取到cgroup的实现，然后调用实现方法获取限制

获取cgroup2实现如下

func newCGroups2From(mountInfoPath, procPathCGroup string) (*CGroups2, error) {// 检查是否是cgroup2// 通过/proc/self/mountinfo中文件系统类型是否为cgroup2或者挂载点在/sys/fs/cgroupisV2, err := isCGroupV2(mountInfoPath)if err != nil {return nil, err}if !isV2 {return nil, ErrNotV2}// 从/proc/self/cgroup解析子系统对应的cgroupsubsystems, err := parseCGroupSubsystems(procPathCGroup)if err != nil {return nil, err}// Find v2 subsystem by looking for the `0` id// 找到v2子系统var v2subsys *CGroupSubsysfor _, subsys := range subsystems {if subsys.ID == 0 {v2subsys = subsysbreak}}if v2subsys == nil {return nil, ErrNotV2}return &CGroups2{mountPoint: _cgroupv2MountPoint,groupPath:  v2subsys.Name,cpuMaxFile: _cgroupv2CPUMax,}, nil
}

具体算限制方法如下

其实就是取cpu.max文件中指定的限额

// CPUQuota returns the CPU quota applied with the CPU cgroup2 controller.
// It is a result of reading cpu quota and period from cpu.max file.
// It will return `cpu.max / cpu.period`. If cpu.max is set to max, it returns
// (-1, false, nil)
func (cg *CGroups2) CPUQuota() (float64, bool, error) {// 打开/sys/fs/cgroup下对应cgroup的cpu.max文件cpuMaxParams, err := os.Open(path.Join(cg.mountPoint, cg.groupPath, cg.cpuMaxFile))if err != nil {if os.IsNotExist(err) {return -1, false, nil}return -1, false, err}defer cpuMaxParams.Close()scanner := bufio.NewScanner(cpuMaxParams)if scanner.Scan() {fields := strings.Fields(scanner.Text())if len(fields) == 0 || len(fields) > 2 {return -1, false, fmt.Errorf("invalid format")}if fields[_cgroupv2CPUMaxQuotaIndex] == _cgroupV2CPUMaxQuotaMax {return -1, false, nil}// 解析最大额度max, err := strconv.Atoi(fields[_cgroupv2CPUMaxQuotaIndex])if err != nil {return -1, false, err}var period intif len(fields) == 1 {period = _cgroupV2CPUMaxDefaultPeriod} else {period, err = strconv.Atoi(fields[_cgroupv2CPUMaxPeriodIndex])if err != nil {return -1, false, err}if period == 0 {return -1, false, errors.New("zero value for period is not allowed")}}// 返回限额// 也就是最大额度除以周期return float64(max) / float64(period), true, nil}if err := scanner.Err(); err != nil {return -1, false, err}return 0, false, io.ErrUnexpectedEOF
}