1// Copyright 2019 The Prometheus Authors
2// Licensed under the Apache License, Version 2.0 (the "License");
3// you may not use this file except in compliance with the License.
4// You may obtain a copy of the License at
5//
6// http://www.apache.org/licenses/LICENSE-2.0
7//
8// Unless required by applicable law or agreed to in writing, software
9// distributed under the License is distributed on an "AS IS" BASIS,
10// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
11// See the License for the specific language governing permissions and
12// limitations under the License.
13
14package procfs
15
16import (
17	"fmt"
18	"strconv"
19	"strings"
20
21	"github.com/prometheus/procfs/internal/util"
22)
23
24// LoadAvg represents an entry in /proc/loadavg
25type LoadAvg struct {
26	Load1  float64
27	Load5  float64
28	Load15 float64
29}
30
31// LoadAvg returns loadavg from /proc.
32func (fs FS) LoadAvg() (*LoadAvg, error) {
33	path := fs.proc.Path("loadavg")
34
35	data, err := util.ReadFileNoStat(path)
36	if err != nil {
37		return nil, err
38	}
39	return parseLoad(data)
40}
41
42// Parse /proc loadavg and return 1m, 5m and 15m.
43func parseLoad(loadavgBytes []byte) (*LoadAvg, error) {
44	loads := make([]float64, 3)
45	parts := strings.Fields(string(loadavgBytes))
46	if len(parts) < 3 {
47		return nil, fmt.Errorf("malformed loadavg line: too few fields in loadavg string: %q", string(loadavgBytes))
48	}
49
50	var err error
51	for i, load := range parts[0:3] {
52		loads[i], err = strconv.ParseFloat(load, 64)
53		if err != nil {
54			return nil, fmt.Errorf("could not parse load %q: %w", load, err)
55		}
56	}
57	return &LoadAvg{
58		Load1:  loads[0],
59		Load5:  loads[1],
60		Load15: loads[2],
61	}, nil
62}
63