telegraf/plugins/inputs/bcache/bcache.go

143 lines
3.1 KiB
Go

package bcache
import (
"errors"
"io/ioutil"
"os"
"path/filepath"
"strconv"
"strings"
"github.com/influxdata/telegraf"
"github.com/influxdata/telegraf/plugins/inputs"
)
type Bcache struct {
BcachePath string
BcacheDevs []string
}
var sampleConfig = `
## Bcache sets path
## If not specified, then default is:
bcachePath = "/sys/fs/bcache"
## By default, telegraf gather stats for all bcache devices
## Setting devices will restrict the stats to the specified
## bcache devices.
bcacheDevs = ["bcache0"]
`
func (b *Bcache) SampleConfig() string {
return sampleConfig
}
func (b *Bcache) Description() string {
return "Read metrics of bcache from stats_total and dirty_data"
}
func getTags(bdev string) map[string]string {
backingDevFile, _ := os.Readlink(bdev)
backingDevPath := strings.Split(backingDevFile, "/")
backingDev := backingDevPath[len(backingDevPath)-2]
bcacheDevFile, _ := os.Readlink(bdev + "/dev")
bcacheDevPath := strings.Split(bcacheDevFile, "/")
bcacheDev := bcacheDevPath[len(bcacheDevPath)-1]
return map[string]string{"backing_dev": backingDev, "bcache_dev": bcacheDev}
}
func prettyToBytes(v string) uint64 {
var factors = map[string]uint64{
"k": 1 << 10,
"M": 1 << 20,
"G": 1 << 30,
"T": 1 << 40,
"P": 1 << 50,
"E": 1 << 60,
}
var factor uint64
factor = 1
prefix := v[len(v)-1:]
if factors[prefix] != 0 {
v = v[:len(v)-1]
factor = factors[prefix]
}
result, _ := strconv.ParseFloat(v, 32)
result = result * float64(factor)
return uint64(result)
}
func (b *Bcache) gatherBcache(bdev string, acc telegraf.Accumulator) error {
tags := getTags(bdev)
metrics, err := filepath.Glob(bdev + "/stats_total/*")
if len(metrics) < 0 {
return errors.New("Can't read any stats file")
}
file, err := ioutil.ReadFile(bdev + "/dirty_data")
if err != nil {
return err
}
rawValue := strings.TrimSpace(string(file))
value := prettyToBytes(rawValue)
fields := make(map[string]interface{})
fields["dirty_data"] = value
for _, path := range metrics {
key := filepath.Base(path)
file, err := ioutil.ReadFile(path)
rawValue := strings.TrimSpace(string(file))
if err != nil {
return err
}
if key == "bypassed" {
value := prettyToBytes(rawValue)
fields[key] = value
} else {
value, _ := strconv.ParseUint(rawValue, 10, 64)
fields[key] = value
}
}
acc.AddFields("bcache", fields, tags)
return nil
}
func (b *Bcache) Gather(acc telegraf.Accumulator) error {
bcacheDevsChecked := make(map[string]bool)
var restrictDevs bool
if len(b.BcacheDevs) != 0 {
restrictDevs = true
for _, bcacheDev := range b.BcacheDevs {
bcacheDevsChecked[bcacheDev] = true
}
}
bcachePath := b.BcachePath
if len(bcachePath) == 0 {
bcachePath = "/sys/fs/bcache"
}
bdevs, _ := filepath.Glob(bcachePath + "/*/bdev*")
if len(bdevs) < 1 {
return errors.New("Can't find any bcache device")
}
for _, bdev := range bdevs {
if restrictDevs {
bcacheDev := getTags(bdev)["bcache_dev"]
if !bcacheDevsChecked[bcacheDev] {
continue
}
}
b.gatherBcache(bdev, acc)
}
return nil
}
func init() {
inputs.Add("bcache", func() telegraf.Input {
return &Bcache{}
})
}