119 lines
2.9 KiB
Go
119 lines
2.9 KiB
Go
|
// 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 (
|
||
|
|
"bufio"
|
||
|
|
"errors"
|
||
|
|
"os"
|
||
|
|
"regexp"
|
||
|
|
"strconv"
|
||
|
|
)
|
||
|
|
|
||
|
|
var (
|
||
|
|
cpuLineRE = regexp.MustCompile(`cpu(\d+) (\d+) (\d+) (\d+) (\d+) (\d+) (\d+) (\d+) (\d+) (\d+)`)
|
||
|
|
procLineRE = regexp.MustCompile(`(\d+) (\d+) (\d+)`)
|
||
|
|
)
|
||
|
|
|
||
|
|
// Schedstat contains scheduler statistics from /proc/schedstat
|
||
|
|
//
|
||
|
|
// See
|
||
|
|
// https://www.kernel.org/doc/Documentation/scheduler/sched-stats.txt
|
||
|
|
// for a detailed description of what these numbers mean.
|
||
|
|
//
|
||
|
|
// Note the current kernel documentation claims some of the time units are in
|
||
|
|
// jiffies when they are actually in nanoseconds since 2.6.23 with the
|
||
|
|
// introduction of CFS. A fix to the documentation is pending. See
|
||
|
|
// https://lore.kernel.org/patchwork/project/lkml/list/?series=403473
|
||
|
|
type Schedstat struct {
|
||
|
|
CPUs []*SchedstatCPU
|
||
|
|
}
|
||
|
|
|
||
|
|
// SchedstatCPU contains the values from one "cpu<N>" line
|
||
|
|
type SchedstatCPU struct {
|
||
|
|
CPUNum string
|
||
|
|
|
||
|
|
RunningNanoseconds uint64
|
||
|
|
WaitingNanoseconds uint64
|
||
|
|
RunTimeslices uint64
|
||
|
|
}
|
||
|
|
|
||
|
|
// ProcSchedstat contains the values from /proc/<pid>/schedstat
|
||
|
|
type ProcSchedstat struct {
|
||
|
|
RunningNanoseconds uint64
|
||
|
|
WaitingNanoseconds uint64
|
||
|
|
RunTimeslices uint64
|
||
|
|
}
|
||
|
|
|
||
|
|
// Schedstat reads data from /proc/schedstat
|
||
|
|
func (fs FS) Schedstat() (*Schedstat, error) {
|
||
|
|
file, err := os.Open(fs.proc.Path("schedstat"))
|
||
|
|
if err != nil {
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
defer file.Close()
|
||
|
|
|
||
|
|
stats := &Schedstat{}
|
||
|
|
scanner := bufio.NewScanner(file)
|
||
|
|
|
||
|
|
for scanner.Scan() {
|
||
|
|
match := cpuLineRE.FindStringSubmatch(scanner.Text())
|
||
|
|
if match != nil {
|
||
|
|
cpu := &SchedstatCPU{}
|
||
|
|
cpu.CPUNum = match[1]
|
||
|
|
|
||
|
|
cpu.RunningNanoseconds, err = strconv.ParseUint(match[8], 10, 64)
|
||
|
|
if err != nil {
|
||
|
|
continue
|
||
|
|
}
|
||
|
|
|
||
|
|
cpu.WaitingNanoseconds, err = strconv.ParseUint(match[9], 10, 64)
|
||
|
|
if err != nil {
|
||
|
|
continue
|
||
|
|
}
|
||
|
|
|
||
|
|
cpu.RunTimeslices, err = strconv.ParseUint(match[10], 10, 64)
|
||
|
|
if err != nil {
|
||
|
|
continue
|
||
|
|
}
|
||
|
|
|
||
|
|
stats.CPUs = append(stats.CPUs, cpu)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
return stats, nil
|
||
|
|
}
|
||
|
|
|
||
|
|
func parseProcSchedstat(contents string) (stats ProcSchedstat, err error) {
|
||
|
|
match := procLineRE.FindStringSubmatch(contents)
|
||
|
|
|
||
|
|
if match != nil {
|
||
|
|
stats.RunningNanoseconds, err = strconv.ParseUint(match[1], 10, 64)
|
||
|
|
if err != nil {
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
stats.WaitingNanoseconds, err = strconv.ParseUint(match[2], 10, 64)
|
||
|
|
if err != nil {
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
stats.RunTimeslices, err = strconv.ParseUint(match[3], 10, 64)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
err = errors.New("could not parse schedstat")
|
||
|
|
return
|
||
|
|
}
|