// Collect reads cpu.stat for cgroups and per process cpu.stat
// entries for all processes in the cgroup
func (s *PerCgroupStat) Collect() {
file, err := os.Open(s.path + "/" + "cpu.stat")
defer file.Close()
if err != nil {
return
}
scanner := bufio.NewScanner(file)
for scanner.Scan() {
f := regexp.MustCompile("\\s+").Split(scanner.Text(), 2)
if f[0] == "nr_periods" {
s.NrPeriods.Set(misc.ParseUint(f[1]))
}
if f[0] == "nr_throttled" {
s.NrThrottled.Set(misc.ParseUint(f[1]))
}
if f[0] == "throttled_time" {
s.ThrottledTime.Set(misc.ParseUint(f[1]))
}
}
s.CfsPeriodUs.Set(
float64(misc.ReadUintFromFile(
s.path + "/" + "cpu.cfs_period_us")))
// negative values of quota indicate no quota.
// it is not possible for this variable to be zero
s.CfsQuotaUs.Set(
float64(misc.ReadUintFromFile(
s.path + "/" + "cpu.cfs_quota_us")))
// Calculate approximate cumulative CPU usage for all
// processes within this cgroup by calculating difference
// between sum number of ticks.
// We reset between loops because PIDs within cgroup can
// change and sum-counter from previous run can be
// unreliable
s.getCgroupCPUTimes()
time.Sleep(time.Millisecond * 1000)
s.getCgroupCPUTimes()
// Expose summary metrics for easy json access
s.UsageCount.Set(s.usage())
s.UserspaceCount.Set(s.userspace())
s.KernelCount.Set(s.kernel())
s.TotalCount.Set(s.Quota())
s.ThrottleCount.Set(s.Throttle())
// Reset counters
s.Utime.Reset()
s.Stime.Reset()
}
// Unexported functions
func parseCPUline(s *PerCPU, f []string) {
s.User.Set(misc.ParseUint(f[1]))
s.UserLowPrio.Set(misc.ParseUint(f[2]))
s.System.Set(misc.ParseUint(f[3]))
s.Idle.Set(misc.ParseUint(f[4]))
s.Iowait.Set(misc.ParseUint(f[5]))
s.Irq.Set(misc.ParseUint(f[6]))
s.Softirq.Set(misc.ParseUint(f[7]))
s.Steal.Set(misc.ParseUint(f[8]))
s.Guest.Set(misc.ParseUint(f[9]))
s.Total.Set(s.User.Get() + s.UserLowPrio.Get() + s.System.Get() + s.Idle.Get())
}
func getCPUTimes(pid string) (uint64, uint64) {
file, err := os.Open("/proc/" + pid + "/stat")
defer file.Close()
if err != nil {
return 0, 0
}
var user, system uint64
scanner := bufio.NewScanner(file)
for scanner.Scan() {
f := strings.Split(scanner.Text(), " ")
user = misc.ParseUint(f[13])
system = misc.ParseUint(f[14])
}
return user, system
}
// Collect collects per process CPU/Memory/IO metrics
func (s *PerProcessStatMetrics) Collect() {
file, err := os.Open(root + "proc/" + s.Pid + "/stat")
defer file.Close()
if err != nil {
return
}
scanner := bufio.NewScanner(file)
for scanner.Scan() {
f := strings.Split(scanner.Text(), " ")
s.Utime.Set(misc.ParseUint(f[13]))
s.Stime.Set(misc.ParseUint(f[14]))
s.Rss.Set(float64(misc.ParseUint(f[23])))
}
// collect IO metrics
// only works if we are superuser on Linux
file, err = os.Open(root + "proc/" + s.Pid + "/io")
defer file.Close()
if err != nil {
return
}
scanner = bufio.NewScanner(file)
for scanner.Scan() {
f := strings.Split(scanner.Text(), " ")
switch f[0] {
case "read_bytes:":
s.IOReadBytes.Set(misc.ParseUint(f[1]))
case "write_bytes:":
s.IOWriteBytes.Set(misc.ParseUint(f[1]))
}
}
}
// Unexported functions
func parseCgroupMemLine(g *metrics.Gauge, f []string) {
length := len(f)
val := math.NaN()
if length < 2 {
goto fail
}
val = float64(misc.ParseUint(f[1]))
g.Set(val)
return
fail:
g.Set(math.NaN())
return
}
// Unexported functions
func parseMemLine(g *metrics.Gauge, f []string) {
length := len(f)
val := math.NaN()
if length < 2 {
goto fail
}
val = float64(misc.ParseUint(f[1]))
if length > 2 && f[2] == "kB" {
val *= 1024
}
g.Set(val)
return
fail:
g.Set(math.NaN())
return
}
