source: code/trunk/vendor/github.com/prometheus/procfs/loadavg.go@ 822

// 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.

package procfs

import (
        "fmt"
        "strconv"
        "strings"

        "github.com/prometheus/procfs/internal/util"
)

// LoadAvg represents an entry in /proc/loadavg.
type LoadAvg struct {
        Load1  float64
        Load5  float64
        Load15 float64
}

// LoadAvg returns loadavg from /proc.
func (fs FS) LoadAvg() (*LoadAvg, error) {
        path := fs.proc.Path("loadavg")

        data, err := util.ReadFileNoStat(path)
        if err != nil {
                return nil, err
        }
        return parseLoad(data)
}

// Parse /proc loadavg and return 1m, 5m and 15m.
func parseLoad(loadavgBytes []byte) (*LoadAvg, error) {
        loads := make([]float64, 3)
        parts := strings.Fields(string(loadavgBytes))
        if len(parts) < 3 {
                return nil, fmt.Errorf("malformed loadavg line: too few fields in loadavg string: %q", string(loadavgBytes))
        }

        var err error
        for i, load := range parts[0:3] {
                loads[i], err = strconv.ParseFloat(load, 64)
                if err != nil {
                        return nil, fmt.Errorf("could not parse load %q: %w", load, err)
                }
        }
        return &LoadAvg{
                Load1:  loads[0],
                Load5:  loads[1],
                Load15: loads[2],
        }, nil
}