node_exporter/collector/loadavg.go

58 lines
1.0 KiB
Go

// +build !noloadavg
package collector
import (
"errors"
"fmt"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/log"
)
// #include <stdlib.h>
import "C"
var loadavg [1]C.double
type loadavgCollector struct {
metric prometheus.Gauge
}
func init() {
Factories["loadavg"] = NewLoadavgCollector
loadavg[0] = 0
}
// load1 stat.
func NewLoadavgCollector() (Collector, error) {
return &loadavgCollector{
metric: prometheus.NewGauge(prometheus.GaugeOpts{
Namespace: Namespace,
Name: "load1",
Help: "1m load average.",
}),
}, nil
}
func (c *loadavgCollector) Update(ch chan<- prometheus.Metric) (err error) {
load, err := getLoad1()
if err != nil {
return fmt.Errorf("Couldn't get load: %s", err)
}
log.Debugf("Set node_load: %f", load)
c.metric.Set(load)
c.metric.Collect(ch)
return err
}
func getLoad1() (float64, error) {
samples := C.getloadavg(&loadavg[0], 1)
if samples > 0 {
return float64(loadavg[0]), nil
} else {
return 0, errors.New("Failed to get load average!")
}
}