node_exporter/collector/rapl_linux.go

96 lines
2.5 KiB
Go

// Copyright 2019 The Prometheus Authors
// 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.
// +build !norapl
package collector
import (
"errors"
"fmt"
"os"
"strconv"
"github.com/go-kit/log"
"github.com/go-kit/log/level"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/procfs/sysfs"
)
type raplCollector struct {
fs sysfs.FS
logger log.Logger
}
func init() {
registerCollector("rapl", defaultEnabled, NewRaplCollector)
}
// NewRaplCollector returns a new Collector exposing RAPL metrics.
func NewRaplCollector(logger log.Logger) (Collector, error) {
fs, err := sysfs.NewFS(*sysPath)
if err != nil {
return nil, err
}
collector := raplCollector{
fs: fs,
logger: logger,
}
return &collector, nil
}
// Update implements Collector and exposes RAPL related metrics.
func (c *raplCollector) Update(ch chan<- prometheus.Metric) error {
// nil zones are fine when platform doesn't have powercap files present.
zones, err := sysfs.GetRaplZones(c.fs)
if err != nil {
if errors.Is(err, os.ErrNotExist) {
level.Debug(c.logger).Log("msg", "Platform doesn't have powercap files present", "err", err)
return ErrNoData
}
if errors.Is(err, os.ErrPermission) {
level.Debug(c.logger).Log("msg", "Can't access powercap files", "err", err)
return ErrNoData
}
return fmt.Errorf("failed to retrieve rapl stats: %w", err)
}
for _, rz := range zones {
newMicrojoules, err := rz.GetEnergyMicrojoules()
if err != nil {
if errors.Is(err, os.ErrPermission) {
level.Debug(c.logger).Log("msg", "Can't access energy_uj file", "zone", rz, "err", err)
return ErrNoData
}
return err
}
index := strconv.Itoa(rz.Index)
descriptor := prometheus.NewDesc(
prometheus.BuildFQName(namespace, "rapl", rz.Name+"_joules_total"),
"Current RAPL "+rz.Name+" value in joules",
[]string{"index"}, nil,
)
ch <- prometheus.MustNewConstMetric(
descriptor,
prometheus.CounterValue,
float64(newMicrojoules)/1000000.0,
index,
)
}
return nil
}