+// Copyright (C) The Arvados Authors. All rights reserved.
+//
+// SPDX-License-Identifier: AGPL-3.0
+
package main
import (
"flag"
"fmt"
"io"
- "io/ioutil"
"log"
"os"
"os/exec"
"os/signal"
- "strings"
"syscall"
"time"
+
+ "git.curoverse.com/arvados.git/lib/crunchstat"
)
-func CopyPipeToChan(in io.Reader, out chan string, done chan<- bool) {
- s := bufio.NewScanner(in)
- for s.Scan() {
- out <- s.Text()
- }
- done <- true
-}
+const MaxLogLine = 1 << 14 // Child stderr lines >16KiB will be split
-func CopyChanToPipe(in <-chan string, out io.Writer) {
- for s := range in {
- fmt.Fprintln(out, s)
- }
-}
+var (
+ signalOnDeadPPID int = 15
+ ppidCheckInterval = time.Second
+ version = "dev"
+)
-func OpenAndReadAll(filename string, log_chan chan<- string) ([]byte, error) {
- in, err := os.Open(filename)
- if err != nil {
- if log_chan != nil {
- log_chan <- fmt.Sprintf("open %s: %s", filename, err)
- }
- return nil, err
- }
- defer in.Close()
- {
- content, err := ioutil.ReadAll(in)
- if err != nil && log_chan != nil {
- log_chan <- fmt.Sprintf("read %s: %s", filename, err)
- }
- return content, err
+func main() {
+ reporter := crunchstat.Reporter{
+ Logger: log.New(os.Stderr, "crunchstat: ", 0),
}
-}
-func FindStat(cgroup_root string, cgroup_parent string, container_id string, statgroup string, stat string) string {
- var path string
- path = fmt.Sprintf("%s/%s/%s/%s/%s.%s", cgroup_root, statgroup, cgroup_parent, container_id, statgroup, stat)
- if _, err := os.Stat(path); err == nil {
- return path
- }
- path = fmt.Sprintf("%s/%s/%s/%s.%s", cgroup_root, cgroup_parent, container_id, statgroup, stat)
- if _, err := os.Stat(path); err == nil {
- return path
- }
- path = fmt.Sprintf("%s/%s/%s.%s", cgroup_root, statgroup, statgroup, stat)
- if _, err := os.Stat(path); err == nil {
- return path
- }
- path = fmt.Sprintf("%s/%s.%s", cgroup_root, statgroup, stat)
- if _, err := os.Stat(path); err == nil {
- return path
- }
- return ""
-}
+ flag.StringVar(&reporter.CgroupRoot, "cgroup-root", "", "Root of cgroup tree")
+ flag.StringVar(&reporter.CgroupParent, "cgroup-parent", "", "Name of container parent under cgroup")
+ flag.StringVar(&reporter.CIDFile, "cgroup-cid", "", "Path to container id file")
+ flag.IntVar(&signalOnDeadPPID, "signal-on-dead-ppid", signalOnDeadPPID, "Signal to send child if crunchstat's parent process disappears (0 to disable)")
+ flag.DurationVar(&ppidCheckInterval, "ppid-check-interval", ppidCheckInterval, "Time between checks for parent process disappearance")
+ pollMsec := flag.Int64("poll", 1000, "Reporting interval, in milliseconds")
+ getVersion := flag.Bool("version", false, "Print version information and exit.")
-func PollCgroupStats(cgroup_root string, cgroup_parent string, container_id string, stderr chan string, poll int64, stop_poll_chan <-chan bool) {
- var last_user int64 = -1
- var last_sys int64 = -1
- var last_cpucount int64 = 0
+ flag.Parse()
- type Disk struct {
- last_read int64
- next_read int64
- last_write int64
- next_write int64
+ // Print version information if requested
+ if *getVersion {
+ fmt.Printf("crunchstat %s\n", version)
+ return
}
- disk := make(map[string]*Disk)
-
- cpuacct_stat := FindStat(cgroup_root, cgroup_parent, container_id, "cpuacct", "stat")
- blkio_io_service_bytes := FindStat(cgroup_root, cgroup_parent, container_id, "blkio", "io_service_bytes")
- cpuset_cpus := FindStat(cgroup_root, cgroup_parent, container_id, "cpuset", "cpus")
- memory_stat := FindStat(cgroup_root, cgroup_parent, container_id, "memory", "stat")
+ reporter.Logger.Printf("crunchstat %s started", version)
- if cpuacct_stat != "" {
- stderr <- fmt.Sprintf("crunchstat: reading stats from %s", cpuacct_stat)
+ if reporter.CgroupRoot == "" {
+ reporter.Logger.Fatal("error: must provide -cgroup-root")
+ } else if signalOnDeadPPID < 0 {
+ reporter.Logger.Fatalf("-signal-on-dead-ppid=%d is invalid (use a positive signal number, or 0 to disable)", signalOnDeadPPID)
}
- if blkio_io_service_bytes != "" {
- stderr <- fmt.Sprintf("crunchstat: reading stats from %s", blkio_io_service_bytes)
- }
- if cpuset_cpus != "" {
- stderr <- fmt.Sprintf("crunchstat: reading stats from %s", cpuset_cpus)
- }
- if memory_stat != "" {
- stderr <- fmt.Sprintf("crunchstat: reading stats from %s", memory_stat)
- }
-
- poll_chan := make(chan bool, 1)
- go func() {
- // Send periodic poll events.
- poll_chan <- true
- for {
- time.Sleep(time.Duration(poll) * time.Millisecond)
- poll_chan <- true
- }
- }()
- for {
- bedtime := time.Now()
- select {
- case <-stop_poll_chan:
- return
- case <-poll_chan:
- // Emit stats, then select again.
- }
- morning := time.Now()
- elapsed := morning.Sub(bedtime).Nanoseconds() / int64(time.Millisecond)
- var cpus int64 = 0
- if cpuset_cpus != "" {
- b, err := OpenAndReadAll(cpuset_cpus, stderr)
- if err != nil {
- // cgroup probably gone -- skip other stats too.
- continue
- }
- sp := strings.Split(string(b), ",")
- for _, v := range sp {
- var min, max int64
- n, _ := fmt.Sscanf(v, "%d-%d", &min, &max)
- if n == 2 {
- cpus += (max - min) + 1
- } else {
- cpus += 1
- }
- }
-
- if cpus != last_cpucount {
- stderr <- fmt.Sprintf("crunchstat: cpuset.cpus %v", cpus)
- }
- last_cpucount = cpus
- }
- if cpus == 0 {
- cpus = 1
- }
- if cpuacct_stat != "" {
- b, err := OpenAndReadAll(cpuacct_stat, stderr)
- if err != nil {
- // Next time around, last_user would
- // be >1 interval old, so stats will
- // be incorrect. Start over instead.
- last_user = -1
-
- // cgroup probably gone -- skip other stats too.
- continue
- }
- var next_user int64
- var next_sys int64
- fmt.Sscanf(string(b), "user %d\nsystem %d", &next_user, &next_sys)
+ reporter.PollPeriod = time.Duration(*pollMsec) * time.Millisecond
- if elapsed > 0 && last_user != -1 {
- user_diff := next_user - last_user
- sys_diff := next_sys - last_sys
- // Assume we're reading stats based on 100
- // jiffies per second. Because the elapsed
- // time is in milliseconds, we need to boost
- // that to 1000 jiffies per second, then boost
- // it by another 100x to get a percentage, then
- // finally divide by the actual elapsed time
- // and the number of cpus to get average load
- // over the polling period.
- user_pct := (user_diff * 10 * 100) / (elapsed * cpus)
- sys_pct := (sys_diff * 10 * 100) / (elapsed * cpus)
+ reporter.Start()
+ err := runCommand(flag.Args(), reporter.Logger)
+ reporter.Stop()
- stderr <- fmt.Sprintf("crunchstat: cpuacct.stat user %v", user_pct)
- stderr <- fmt.Sprintf("crunchstat: cpuacct.stat sys %v", sys_pct)
- }
+ if err, ok := err.(*exec.ExitError); ok {
+ // The program has exited with an exit code != 0
- last_user = next_user
- last_sys = next_sys
- }
- if blkio_io_service_bytes != "" {
- c, err := os.Open(blkio_io_service_bytes)
- if err != nil {
- stderr <- fmt.Sprintf("open %s: %s", blkio_io_service_bytes, err)
- // cgroup probably gone -- skip other stats too.
- continue
- }
- defer c.Close()
- b := bufio.NewScanner(c)
- var device, op string
- var next int64
- for b.Scan() {
- if _, err := fmt.Sscanf(string(b.Text()), "%s %s %d", &device, &op, &next); err != nil {
- continue
- }
- if disk[device] == nil {
- disk[device] = new(Disk)
- }
- if op == "Read" {
- disk[device].last_read = disk[device].next_read
- disk[device].next_read = next
- if disk[device].last_read > 0 && (disk[device].next_read != disk[device].last_read) {
- stderr <- fmt.Sprintf("crunchstat: blkio.io_service_bytes %s read %v", device, disk[device].next_read-disk[device].last_read)
- }
- }
- if op == "Write" {
- disk[device].last_write = disk[device].next_write
- disk[device].next_write = next
- if disk[device].last_write > 0 && (disk[device].next_write != disk[device].last_write) {
- stderr <- fmt.Sprintf("crunchstat: blkio.io_service_bytes %s write %v", device, disk[device].next_write-disk[device].last_write)
- }
- }
- }
- }
-
- if memory_stat != "" {
- c, err := os.Open(memory_stat)
- if err != nil {
- stderr <- fmt.Sprintf("open %s: %s", memory_stat, err)
- // cgroup probably gone -- skip other stats too.
- continue
- }
- b := bufio.NewScanner(c)
- var stat string
- var val int64
- for b.Scan() {
- if _, err := fmt.Sscanf(string(b.Text()), "%s %d", &stat, &val); err == nil {
- if stat == "rss" {
- stderr <- fmt.Sprintf("crunchstat: memory.stat rss %v", val)
- }
- }
- }
- c.Close()
+ // This works on both Unix and Windows. Although
+ // package syscall is generally platform dependent,
+ // WaitStatus is defined for both Unix and Windows and
+ // in both cases has an ExitStatus() method with the
+ // same signature.
+ if status, ok := err.Sys().(syscall.WaitStatus); ok {
+ os.Exit(status.ExitStatus())
+ } else {
+ reporter.Logger.Fatalln("ExitError without WaitStatus:", err)
}
+ } else if err != nil {
+ reporter.Logger.Fatalln("error in cmd.Wait:", err)
}
}
-func run(logger *log.Logger) error {
+func runCommand(argv []string, logger *log.Logger) error {
+ cmd := exec.Command(argv[0], argv[1:]...)
- var (
- cgroup_root string
- cgroup_parent string
- cgroup_cidfile string
- wait int64
- poll int64
- )
+ logger.Println("Running", argv)
- flag.StringVar(&cgroup_root, "cgroup-root", "", "Root of cgroup tree")
- flag.StringVar(&cgroup_parent, "cgroup-parent", "", "Name of container parent under cgroup")
- flag.StringVar(&cgroup_cidfile, "cgroup-cid", "", "Path to container id file")
- flag.Int64Var(&wait, "wait", 5, "Maximum time (in seconds) to wait for cid file to show up")
- flag.Int64Var(&poll, "poll", 1000, "Polling frequency, in milliseconds")
+ // Child process will use our stdin and stdout pipes
+ // (we close our copies below)
+ cmd.Stdin = os.Stdin
+ cmd.Stdout = os.Stdout
- flag.Parse()
+ // Forward SIGINT and SIGTERM to child process
+ sigChan := make(chan os.Signal, 1)
+ go func(sig <-chan os.Signal) {
+ catch := <-sig
+ if cmd.Process != nil {
+ cmd.Process.Signal(catch)
+ }
+ logger.Println("notice: caught signal:", catch)
+ }(sigChan)
+ signal.Notify(sigChan, syscall.SIGTERM)
+ signal.Notify(sigChan, syscall.SIGINT)
- if cgroup_root == "" {
- logger.Fatal("Must provide -cgroup-root")
+ // Kill our child proc if our parent process disappears
+ if signalOnDeadPPID != 0 {
+ go sendSignalOnDeadPPID(ppidCheckInterval, signalOnDeadPPID, os.Getppid(), cmd, logger)
}
- stderr_chan := make(chan string, 1)
- defer close(stderr_chan)
- finish_chan := make(chan bool)
- defer close(finish_chan)
-
- go CopyChanToPipe(stderr_chan, os.Stderr)
-
- var cmd *exec.Cmd
-
- if len(flag.Args()) > 0 {
- // Set up subprocess
- cmd = exec.Command(flag.Args()[0], flag.Args()[1:]...)
+ // Funnel stderr through our channel
+ stderr_pipe, err := cmd.StderrPipe()
+ if err != nil {
+ logger.Fatalln("error in StderrPipe:", err)
+ }
- logger.Print("Running ", flag.Args())
+ // Run subprocess
+ if err := cmd.Start(); err != nil {
+ logger.Fatalln("error in cmd.Start:", err)
+ }
- // Child process will use our stdin and stdout pipes
- // (we close our copies below)
- cmd.Stdin = os.Stdin
- cmd.Stdout = os.Stdout
+ // Close stdin/stdout in this (parent) process
+ os.Stdin.Close()
+ os.Stdout.Close()
- // Forward SIGINT and SIGTERM to inner process
- term := make(chan os.Signal, 1)
- go func(sig <-chan os.Signal) {
- catch := <-sig
- if cmd.Process != nil {
- cmd.Process.Signal(catch)
- }
- logger.Print("caught signal: ", catch)
- }(term)
- signal.Notify(term, syscall.SIGTERM)
- signal.Notify(term, syscall.SIGINT)
+ copyPipeToChildLog(stderr_pipe, log.New(os.Stderr, "", 0))
- // Funnel stderr through our channel
- stderr_pipe, err := cmd.StderrPipe()
- if err != nil {
- logger.Fatal(err)
- }
- go CopyPipeToChan(stderr_pipe, stderr_chan, finish_chan)
+ return cmd.Wait()
+}
- // Run subprocess
- if err := cmd.Start(); err != nil {
- logger.Fatal(err)
+func sendSignalOnDeadPPID(intvl time.Duration, signum, ppidOrig int, cmd *exec.Cmd, logger *log.Logger) {
+ ticker := time.NewTicker(intvl)
+ for range ticker.C {
+ ppid := os.Getppid()
+ if ppid == ppidOrig {
+ continue
}
-
- // Close stdin/stdout in this (parent) process
- os.Stdin.Close()
- os.Stdout.Close()
- }
-
- // Read the cid file
- var container_id string
- if cgroup_cidfile != "" {
- // wait up to 'wait' seconds for the cid file to appear
- ok := false
- var i time.Duration
- for i = 0; i < time.Duration(wait)*time.Second; i += (100 * time.Millisecond) {
- cid, err := OpenAndReadAll(cgroup_cidfile, nil)
- if err == nil && len(cid) > 0 {
- ok = true
- container_id = string(cid)
- break
- }
- time.Sleep(100 * time.Millisecond)
+ if cmd.Process == nil {
+ // Child process isn't running yet
+ continue
}
- if !ok {
- logger.Printf("Could not read cid file %s", cgroup_cidfile)
+ logger.Printf("notice: crunchstat ppid changed from %d to %d -- killing child pid %d with signal %d", ppidOrig, ppid, cmd.Process.Pid, signum)
+ err := cmd.Process.Signal(syscall.Signal(signum))
+ if err != nil {
+ logger.Printf("error: sending signal: %s", err)
+ continue
}
+ ticker.Stop()
+ break
}
-
- stop_poll_chan := make(chan bool, 1)
- go PollCgroupStats(cgroup_root, cgroup_parent, container_id, stderr_chan, poll, stop_poll_chan)
-
- // When the child exits, tell the polling goroutine to stop.
- defer func() { stop_poll_chan <- true }()
-
- // Wait for CopyPipeToChan to consume child's stderr pipe
- <-finish_chan
-
- return cmd.Wait()
}
-func main() {
- logger := log.New(os.Stderr, "crunchstat: ", 0)
- if err := run(logger); err != nil {
- if exiterr, ok := err.(*exec.ExitError); ok {
- // The program has exited with an exit code != 0
-
- // This works on both Unix and
- // Windows. Although package syscall is
- // generally platform dependent, WaitStatus is
- // defined for both Unix and Windows and in
- // both cases has an ExitStatus() method with
- // the same signature.
- if status, ok := exiterr.Sys().(syscall.WaitStatus); ok {
- os.Exit(status.ExitStatus())
- }
+func copyPipeToChildLog(in io.ReadCloser, logger *log.Logger) {
+ reader := bufio.NewReaderSize(in, MaxLogLine)
+ var prefix string
+ for {
+ line, isPrefix, err := reader.ReadLine()
+ if err == io.EOF {
+ break
+ } else if err != nil {
+ logger.Fatal("error reading child stderr:", err)
+ }
+ var suffix string
+ if isPrefix {
+ suffix = "[...]"
+ }
+ logger.Print(prefix, string(line), suffix)
+ // Set up prefix for following line
+ if isPrefix {
+ prefix = "[...]"
} else {
- logger.Fatalf("cmd.Wait: %v", err)
+ prefix = ""
}
}
+ in.Close()
}