1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192
|
// Copyright 2018 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 (
"bytes"
"fmt"
"os"
"github.com/prometheus/procfs/internal/fs"
"github.com/prometheus/procfs/internal/util"
)
// Originally, this USER_HZ value was dynamically retrieved via a sysconf call
// which required cgo. However, that caused a lot of problems regarding
// cross-compilation. Alternatives such as running a binary to determine the
// value, or trying to derive it in some other way were all problematic. After
// much research it was determined that USER_HZ is actually hardcoded to 100 on
// all Go-supported platforms as of the time of this writing. This is why we
// decided to hardcode it here as well. It is not impossible that there could
// be systems with exceptions, but they should be very exotic edge cases, and
// in that case, the worst outcome will be two misreported metrics.
//
// See also the following discussions:
//
// - https://github.com/prometheus/node_exporter/issues/52
// - https://github.com/prometheus/procfs/pull/2
// - http://stackoverflow.com/questions/17410841/how-does-user-hz-solve-the-jiffy-scaling-issue
const userHZ = 100
// ProcStat provides status information about the process,
// read from /proc/[pid]/stat.
type ProcStat struct {
// The process ID.
PID int
// The filename of the executable.
Comm string
// The process state.
State string
// The PID of the parent of this process.
PPID int
// The process group ID of the process.
PGRP int
// The session ID of the process.
Session int
// The controlling terminal of the process.
TTY int
// The ID of the foreground process group of the controlling terminal of
// the process.
TPGID int
// The kernel flags word of the process.
Flags uint
// The number of minor faults the process has made which have not required
// loading a memory page from disk.
MinFlt uint
// The number of minor faults that the process's waited-for children have
// made.
CMinFlt uint
// The number of major faults the process has made which have required
// loading a memory page from disk.
MajFlt uint
// The number of major faults that the process's waited-for children have
// made.
CMajFlt uint
// Amount of time that this process has been scheduled in user mode,
// measured in clock ticks.
UTime uint
// Amount of time that this process has been scheduled in kernel mode,
// measured in clock ticks.
STime uint
// Amount of time that this process's waited-for children have been
// scheduled in user mode, measured in clock ticks.
CUTime uint
// Amount of time that this process's waited-for children have been
// scheduled in kernel mode, measured in clock ticks.
CSTime uint
// For processes running a real-time scheduling policy, this is the negated
// scheduling priority, minus one.
Priority int
// The nice value, a value in the range 19 (low priority) to -20 (high
// priority).
Nice int
// Number of threads in this process.
NumThreads int
// The time the process started after system boot, the value is expressed
// in clock ticks.
Starttime uint64
// Virtual memory size in bytes.
VSize uint
// Resident set size in pages.
RSS int
proc fs.FS
}
// NewStat returns the current status information of the process.
//
// Deprecated: use p.Stat() instead
func (p Proc) NewStat() (ProcStat, error) {
return p.Stat()
}
// Stat returns the current status information of the process.
func (p Proc) Stat() (ProcStat, error) {
data, err := util.ReadFileNoStat(p.path("stat"))
if err != nil {
return ProcStat{}, err
}
var (
ignore int
s = ProcStat{PID: p.PID, proc: p.fs}
l = bytes.Index(data, []byte("("))
r = bytes.LastIndex(data, []byte(")"))
)
if l < 0 || r < 0 {
return ProcStat{}, fmt.Errorf(
"unexpected format, couldn't extract comm: %s",
data,
)
}
s.Comm = string(data[l+1 : r])
_, err = fmt.Fscan(
bytes.NewBuffer(data[r+2:]),
&s.State,
&s.PPID,
&s.PGRP,
&s.Session,
&s.TTY,
&s.TPGID,
&s.Flags,
&s.MinFlt,
&s.CMinFlt,
&s.MajFlt,
&s.CMajFlt,
&s.UTime,
&s.STime,
&s.CUTime,
&s.CSTime,
&s.Priority,
&s.Nice,
&s.NumThreads,
&ignore,
&s.Starttime,
&s.VSize,
&s.RSS,
)
if err != nil {
return ProcStat{}, err
}
return s, nil
}
// VirtualMemory returns the virtual memory size in bytes.
func (s ProcStat) VirtualMemory() uint {
return s.VSize
}
// ResidentMemory returns the resident memory size in bytes.
func (s ProcStat) ResidentMemory() int {
return s.RSS * os.Getpagesize()
}
// StartTime returns the unix timestamp of the process in seconds.
func (s ProcStat) StartTime() (float64, error) {
fs := FS{proc: s.proc}
stat, err := fs.Stat()
if err != nil {
return 0, err
}
return float64(stat.BootTime) + (float64(s.Starttime) / userHZ), nil
}
// CPUTime returns the total CPU user and system time in seconds.
func (s ProcStat) CPUTime() float64 {
return float64(s.UTime+s.STime) / userHZ
}
|