node_exporter/collector/mdadm_linux.go

314 lines
8.6 KiB
Go

// Copyright 2015 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 !nomdadm
package collector
import (
"fmt"
"io/ioutil"
"os"
"regexp"
"strconv"
"strings"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/common/log"
)
var (
statuslineRE = regexp.MustCompile(`(\d+) blocks .*\[(\d+)/(\d+)\] \[[U_]+\]`)
raid0lineRE = regexp.MustCompile(`(\d+) blocks( super ([0-9\.])*)? \d+k chunks`)
buildlineRE = regexp.MustCompile(`\((\d+)/\d+\)`)
unknownPersonalityLineRE = regexp.MustCompile(`(\d+) blocks (.*)`)
raidPersonalityRE = regexp.MustCompile(`raid[0-9]+`)
)
type mdStatus struct {
name string
active bool
disksActive int64
disksTotal int64
blocksTotal int64
blocksSynced int64
}
type mdadmCollector struct{}
func init() {
Factories["mdadm"] = NewMdadmCollector
}
func evalStatusline(statusline string) (active, total, size int64, err error) {
matches := statuslineRE.FindStringSubmatch(statusline)
// +1 to make it more obvious that the whole string containing the info is also returned as matches[0].
if len(matches) < 3+1 {
return 0, 0, 0, fmt.Errorf("too few matches found in statusline: %s", statusline)
} else if len(matches) > 3+1 {
return 0, 0, 0, fmt.Errorf("too many matches found in statusline: %s", statusline)
}
size, err = strconv.ParseInt(matches[1], 10, 64)
if err != nil {
return 0, 0, 0, fmt.Errorf("%s in statusline: %s", err, statusline)
}
total, err = strconv.ParseInt(matches[2], 10, 64)
if err != nil {
return 0, 0, 0, fmt.Errorf("%s in statusline: %s", err, statusline)
}
active, err = strconv.ParseInt(matches[3], 10, 64)
if err != nil {
return 0, 0, 0, fmt.Errorf("%s in statusline: %s", err, statusline)
}
return active, total, size, nil
}
func evalRaid0line(statusline string) (size int64, err error) {
matches := raid0lineRE.FindStringSubmatch(statusline)
if len(matches) < 2 {
return 0, fmt.Errorf("invalid raid0 status line: %s", statusline)
}
size, err = strconv.ParseInt(matches[1], 10, 64)
if err != nil {
return 0, fmt.Errorf("%s in statusline: %s", err, statusline)
}
return size, nil
}
func evalUnknownPersonalitylineRE(statusline string) (size int64, err error) {
matches := unknownPersonalityLineRE.FindStringSubmatch(statusline)
if len(matches) != 2+1 {
return 0, fmt.Errorf("invalid unknown personality status line: %s", statusline)
}
size, err = strconv.ParseInt(matches[1], 10, 64)
if err != nil {
return 0, fmt.Errorf("%s in statusline: %s", err, statusline)
}
return size, nil
}
// evalBuildline gets the size that has already been synced out of the sync-line.
func evalBuildline(buildline string) (int64, error) {
matches := buildlineRE.FindStringSubmatch(buildline)
// +1 to make it more obvious that the whole string containing the info is also returned as matches[0].
if len(matches) < 1+1 {
return 0, fmt.Errorf("too few matches found in buildline: %s", buildline)
}
if len(matches) > 1+1 {
return 0, fmt.Errorf("too many matches found in buildline: %s", buildline)
}
syncedSize, err := strconv.ParseInt(matches[1], 10, 64)
if err != nil {
return 0, fmt.Errorf("%s in buildline: %s", err, buildline)
}
return syncedSize, nil
}
// parseMdstat parses an mdstat-file and returns a struct with the relevant infos.
func parseMdstat(mdStatusFilePath string) ([]mdStatus, error) {
content, err := ioutil.ReadFile(mdStatusFilePath)
if err != nil {
return []mdStatus{}, fmt.Errorf("error parsing mdstat: %s", err)
}
lines := strings.Split(string(content), "\n")
// Each md has at least the deviceline, statusline and one empty line afterwards
// so we will have probably something of the order len(lines)/3 devices
// so we use that for preallocation.
mdStates := make([]mdStatus, 0, len(lines)/3)
for i, line := range lines {
if line == "" {
continue
}
if line[0] == ' ' || line[0] == '\t' {
// Lines starting with white space are not the beginning of a md-section.
continue
}
if strings.HasPrefix(line, "Personalities") || strings.HasPrefix(line, "unused") {
// These lines contain general information.
continue
}
mainLine := strings.Split(line, " ")
if len(mainLine) < 4 {
return mdStates, fmt.Errorf("error parsing mdline: %s", line)
}
md := mdStatus{
name: mainLine[0],
active: mainLine[2] == "active",
}
if len(lines) <= i+3 {
return mdStates, fmt.Errorf("error parsing mdstat: entry for %s has fewer lines than expected", md.name)
}
personality := ""
for _, possiblePersonality := range mainLine[3:] {
if raidPersonalityRE.MatchString(possiblePersonality) {
personality = possiblePersonality
break
}
}
switch {
case personality == "raid0":
md.disksActive = int64(len(mainLine) - 4) // Get the number of devices from the main line.
md.disksTotal = md.disksActive // Raid0 active and total is always the same if active.
md.blocksTotal, err = evalRaid0line(lines[i+1])
case raidPersonalityRE.MatchString(personality):
md.disksActive, md.disksTotal, md.blocksTotal, err = evalStatusline(lines[i+1])
default:
log.Infof("Personality unknown: %s\n", mainLine)
md.blocksTotal, err = evalUnknownPersonalitylineRE(lines[i+1])
}
if err != nil {
return mdStates, fmt.Errorf("error parsing mdstat: %s", err)
}
syncLine := lines[i+2]
if strings.Contains(syncLine, "bitmap") {
syncLine = lines[i+3]
}
// If device is syncing at the moment, get the number of currently synced bytes,
// otherwise that number equals the size of the device.
if strings.Contains(syncLine, "recovery") ||
strings.Contains(syncLine, "resync") &&
!strings.Contains(syncLine, "\tresync=") {
md.blocksSynced, err = evalBuildline(syncLine)
if err != nil {
return mdStates, fmt.Errorf("error parsing mdstat: %s", err)
}
} else {
md.blocksSynced = md.blocksTotal
}
mdStates = append(mdStates, md)
}
return mdStates, nil
}
// NewMdadmCollector returns a new Collector exposing raid statistics.
func NewMdadmCollector() (Collector, error) {
return &mdadmCollector{}, nil
}
var (
isActiveDesc = prometheus.NewDesc(
prometheus.BuildFQName(Namespace, "md", "is_active"),
"Indicator whether the md-device is active or not.",
[]string{"device"},
nil,
)
disksActiveDesc = prometheus.NewDesc(
prometheus.BuildFQName(Namespace, "md", "disks_active"),
"Number of active disks of device.",
[]string{"device"},
nil,
)
disksTotalDesc = prometheus.NewDesc(
prometheus.BuildFQName(Namespace, "md", "disks"),
"Total number of disks of device.",
[]string{"device"},
nil,
)
blocksTotalDesc = prometheus.NewDesc(
prometheus.BuildFQName(Namespace, "md", "blocks"),
"Total number of blocks on device.",
[]string{"device"},
nil,
)
blocksSyncedDesc = prometheus.NewDesc(
prometheus.BuildFQName(Namespace, "md", "blocks_synced"),
"Number of blocks synced on device.",
[]string{"device"},
nil,
)
)
func (c *mdadmCollector) Update(ch chan<- prometheus.Metric) error {
statusfile := procFilePath("mdstat")
if _, err := os.Stat(statusfile); err != nil {
if os.IsNotExist(err) {
log.Debugf("Not collecting mdstat, file does not exist: %s", statusfile)
return nil
}
return err
}
mdstate, err := parseMdstat(statusfile)
if err != nil {
return fmt.Errorf("error parsing mdstatus: %s", err)
}
for _, mds := range mdstate {
log.Debugf("collecting metrics for device %s", mds.name)
var active float64
if mds.active {
active = 1
}
ch <- prometheus.MustNewConstMetric(
isActiveDesc,
prometheus.GaugeValue,
active,
mds.name,
)
ch <- prometheus.MustNewConstMetric(
disksActiveDesc,
prometheus.GaugeValue,
float64(mds.disksActive),
mds.name,
)
ch <- prometheus.MustNewConstMetric(
disksTotalDesc,
prometheus.GaugeValue,
float64(mds.disksTotal),
mds.name,
)
ch <- prometheus.MustNewConstMetric(
blocksTotalDesc,
prometheus.GaugeValue,
float64(mds.blocksTotal),
mds.name,
)
ch <- prometheus.MustNewConstMetric(
blocksSyncedDesc,
prometheus.GaugeValue,
float64(mds.blocksSynced),
mds.name,
)
}
return nil
}