open-nomad/helper/stats/cpu.go
2018-05-10 18:52:54 -04:00

82 lines
1.9 KiB
Go

package stats
import (
"context"
"fmt"
"math"
"sync"
"time"
multierror "github.com/hashicorp/go-multierror"
"github.com/shirou/gopsutil/cpu"
)
const (
// cpuInfoTimeout is the timeout used when gathering CPU info. This is used
// to override the default timeout in gopsutil which has a tendency to
// timeout on Windows.
cpuInfoTimeout = 10 * time.Second
)
var (
cpuMhzPerCore float64
cpuModelName string
cpuNumCores int
cpuTotalTicks float64
initErr error
onceLer sync.Once
)
func Init() error {
onceLer.Do(func() {
var merrs *multierror.Error
var err error
if cpuNumCores, err = cpu.Counts(true); err != nil {
merrs = multierror.Append(merrs, fmt.Errorf("Unable to determine the number of CPU cores available: %v", err))
}
var cpuInfo []cpu.InfoStat
ctx, cancel := context.WithTimeout(context.Background(), cpuInfoTimeout)
defer cancel()
if cpuInfo, err = cpu.InfoWithContext(ctx); err != nil {
merrs = multierror.Append(merrs, fmt.Errorf("Unable to obtain CPU information: %v", err))
}
for _, cpu := range cpuInfo {
cpuModelName = cpu.ModelName
cpuMhzPerCore = cpu.Mhz
break
}
// Floor all of the values such that small difference don't cause the
// node to fall into a unique computed node class
cpuMhzPerCore = math.Floor(cpuMhzPerCore)
cpuTotalTicks = math.Floor(float64(cpuNumCores) * cpuMhzPerCore)
// Set any errors that occurred
initErr = merrs.ErrorOrNil()
})
return initErr
}
// CPUModelName returns the number of CPU cores available
func CPUNumCores() int {
return cpuNumCores
}
// CPUMHzPerCore returns the MHz per CPU core
func CPUMHzPerCore() float64 {
return cpuMhzPerCore
}
// CPUModelName returns the model name of the CPU
func CPUModelName() string {
return cpuModelName
}
// TotalTicksAvailable calculates the total Mhz available across all cores
func TotalTicksAvailable() float64 {
return cpuTotalTicks
}