node_exporter/collector/meminfo_numa_linux.go
Pavel Borzenkov c12d8ea927 Add new per NUMA node memory statistics collector
It is sometimes useful to understand the distribution of free/occupied
memory between NUMA nodes to deal with performance problems. To do so,
add new meminfo_numa collector that enables exporting of per node
statistics along with unit and end-to-end tests for it.

Signed-off-by: Pavel Borzenkov <pavel.borzenkov@gmail.com>
2016-01-15 15:04:27 +03:00

132 lines
3.1 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 !nomeminfo_numa
package collector
import (
"bufio"
"fmt"
"io"
"os"
"path"
"path/filepath"
"regexp"
"strconv"
"strings"
"github.com/prometheus/client_golang/prometheus"
)
const (
memInfoNumaSubsystem = "memory_numa"
)
type meminfoKey struct {
metricName, numaNode string
}
type meminfoNumaCollector struct {
metricDescs map[string]*prometheus.Desc
}
func init() {
Factories["meminfo_numa"] = NewMeminfoNumaCollector
}
// Takes a prometheus registry and returns a new Collector exposing
// memory stats.
func NewMeminfoNumaCollector() (Collector, error) {
return &meminfoNumaCollector{
metricDescs: map[string]*prometheus.Desc{},
}, nil
}
func (c *meminfoNumaCollector) Update(ch chan<- prometheus.Metric) (err error) {
memInfoNuma, err := getMemInfoNuma()
if err != nil {
return fmt.Errorf("couldn't get NUMA meminfo: %s", err)
}
for k, v := range memInfoNuma {
desc, ok := c.metricDescs[k.metricName]
if !ok {
desc = prometheus.NewDesc(
prometheus.BuildFQName(Namespace, memInfoNumaSubsystem, k.metricName),
fmt.Sprintf("Memory information field %s.", k.metricName),
[]string{"node"}, nil)
c.metricDescs[k.metricName] = desc
}
ch <- prometheus.MustNewConstMetric(desc, prometheus.GaugeValue, v, k.numaNode)
}
return nil
}
func getMemInfoNuma() (map[meminfoKey]float64, error) {
info := make(map[meminfoKey]float64)
nodes, err := filepath.Glob(sysFilePath("devices/system/node/node[0-9]*"))
if err != nil {
return nil, err
}
for _, node := range nodes {
file, err := os.Open(path.Join(node, "meminfo"))
if err != nil {
return nil, err
}
defer file.Close()
numaInfo, err := parseMemInfoNuma(file)
if err != nil {
return nil, err
}
for k, v := range numaInfo {
info[k] = v
}
}
return info, nil
}
func parseMemInfoNuma(r io.Reader) (map[meminfoKey]float64, error) {
var (
memInfo = map[meminfoKey]float64{}
scanner = bufio.NewScanner(r)
re = regexp.MustCompile("\\((.*)\\)")
)
for scanner.Scan() {
line := scanner.Text()
parts := strings.Fields(string(line))
fv, err := strconv.ParseFloat(parts[3], 64)
if err != nil {
return nil, fmt.Errorf("invalid value in meminfo: %s", err)
}
switch l := len(parts); {
case l == 4: // no unit
case l == 5 && parts[4] == "kB": // has unit
fv *= 1024
default:
return nil, fmt.Errorf("invalid line in meminfo: %s", line)
}
metric := strings.TrimRight(parts[2], ":")
// Active(anon) -> Active_anon
metric = re.ReplaceAllString(metric, "_${1}")
memInfo[meminfoKey{metric, parts[1]}] = fv
}
return memInfo, nil
}