--- /dev/null
+package crunchstat
+
+import (
+ "bufio"
+ "bytes"
+ "errors"
+ "fmt"
+ "io"
+ "io/ioutil"
+ "log"
+ "os"
+ "strconv"
+ "strings"
+ "time"
+)
+
+// This magically allows us to look up user_hz via _SC_CLK_TCK:
+
+/*
+#include <unistd.h>
+#include <sys/types.h>
+#include <pwd.h>
+#include <stdlib.h>
+*/
+import "C"
+
+// A Reporter gathers statistics for a cgroup and writes them to a
+// log.Logger.
+type Reporter struct {
+ // CID of the container to monitor. If empty, read the CID
+ // from CIDFile.
+ CID string
+ // Where cgroup special files live on this system
+ CgroupRoot string
+ CgroupParent string
+ // Path to a file we can read CID from. If CIDFile is empty or
+ // nonexistent, wait for it to appear.
+ CIDFile string
+
+ // Interval between samples
+ Poll time.Duration
+
+ // Where to write statistics.
+ Logger *log.Logger
+
+ reportedStatFile map[string]string
+ lastNetSample map[string]IoSample
+ lastDiskSample map[string]IoSample
+ lastCPUSample CpuSample
+
+ done chan struct{}
+}
+
+// Wait (if necessary) for the CID to appear in CIDFile, then start
+// reporting statistics.
+//
+// Start should not be called more than once on a Reporter.
+//
+// Public data fields should not be changed after calling Start.
+func (r *Reporter) Start() {
+ r.done = make(chan struct{})
+ go r.run()
+}
+
+// Stop reporting statistics. Do not call more than once, or before
+// calling Start.
+//
+// Nothing will be logged after Stop returns.
+func (r *Reporter) Stop() {
+ close(r.done)
+}
+
+func (r *Reporter) readAllOrWarn(in *os.File) ([]byte, error) {
+ content, err := ioutil.ReadAll(in)
+ if err != nil {
+ r.Logger.Print(err)
+ }
+ return content, err
+}
+
+// Open the cgroup stats file in /sys/fs corresponding to the target
+// cgroup, and return an *os.File. If no stats file is available,
+// return nil.
+//
+// TODO: Instead of trying all options, choose a process in the
+// container, and read /proc/PID/cgroup to determine the appropriate
+// cgroup root for the given statgroup. (This will avoid falling back
+// to host-level stats during container setup and teardown.)
+func (r *Reporter) openStatFile(statgroup string, stat string) (*os.File, error) {
+ var paths []string
+ if r.CID != "" {
+ // Collect container's stats
+ paths = []string{
+ fmt.Sprintf("%s/%s/%s/%s/%s", r.CgroupRoot, statgroup, r.CgroupParent, r.CID, stat),
+ fmt.Sprintf("%s/%s/%s/%s", r.CgroupRoot, r.CgroupParent, r.CID, stat),
+ }
+ } else {
+ // Collect this host's stats
+ paths = []string{
+ fmt.Sprintf("%s/%s/%s", r.CgroupRoot, statgroup, stat),
+ fmt.Sprintf("%s/%s", r.CgroupRoot, stat),
+ }
+ }
+ var path string
+ var file *os.File
+ var err error
+ for _, path = range paths {
+ file, err = os.Open(path)
+ if err == nil {
+ break
+ } else {
+ path = ""
+ }
+ }
+ if pathWas, ok := r.reportedStatFile[stat]; !ok || pathWas != path {
+ // Log whenever we start using a new/different cgroup
+ // stat file for a given statistic. This typically
+ // happens 1 to 3 times per statistic, depending on
+ // whether we happen to collect stats [a] before any
+ // processes have been created in the container and
+ // [b] after all contained processes have exited.
+ if path == "" {
+ r.Logger.Printf("notice: stats not available: stat %s, statgroup %s, cid %s, parent %s, root %s\n", stat, statgroup, r.CID, r.CgroupParent, r.CgroupRoot)
+ } else if ok {
+ r.Logger.Printf("notice: stats moved from %s to %s\n", r.reportedStatFile[stat], path)
+ } else {
+ r.Logger.Printf("notice: reading stats from %s\n", path)
+ }
+ r.reportedStatFile[stat] = path
+ }
+ return file, err
+}
+
+func (r *Reporter) getContainerNetStats() (io.Reader, error) {
+ procsFile, err := r.openStatFile("cpuacct", "cgroup.procs")
+ if err != nil {
+ return nil, err
+ }
+ defer procsFile.Close()
+ reader := bufio.NewScanner(procsFile)
+ for reader.Scan() {
+ taskPid := reader.Text()
+ statsFilename := fmt.Sprintf("/proc/%s/net/dev", taskPid)
+ stats, err := ioutil.ReadFile(statsFilename)
+ if err != nil {
+ r.Logger.Print(err)
+ continue
+ }
+ return strings.NewReader(string(stats)), nil
+ }
+ return nil, errors.New("Could not read stats for any proc in container")
+}
+
+type IoSample struct {
+ sampleTime time.Time
+ txBytes int64
+ rxBytes int64
+}
+
+func (r *Reporter) DoBlkIoStats() {
+ c, err := r.openStatFile("blkio", "blkio.io_service_bytes")
+ if err != nil {
+ return
+ }
+ defer c.Close()
+ b := bufio.NewScanner(c)
+ var sampleTime = time.Now()
+ newSamples := make(map[string]IoSample)
+ for b.Scan() {
+ var device, op string
+ var val int64
+ if _, err := fmt.Sscanf(string(b.Text()), "%s %s %d", &device, &op, &val); err != nil {
+ continue
+ }
+ var thisSample IoSample
+ var ok bool
+ if thisSample, ok = newSamples[device]; !ok {
+ thisSample = IoSample{sampleTime, -1, -1}
+ }
+ switch op {
+ case "Read":
+ thisSample.rxBytes = val
+ case "Write":
+ thisSample.txBytes = val
+ }
+ newSamples[device] = thisSample
+ }
+ for dev, sample := range newSamples {
+ if sample.txBytes < 0 || sample.rxBytes < 0 {
+ continue
+ }
+ delta := ""
+ if prev, ok := r.lastDiskSample[dev]; ok {
+ delta = fmt.Sprintf(" -- interval %.4f seconds %d write %d read",
+ sample.sampleTime.Sub(prev.sampleTime).Seconds(),
+ sample.txBytes-prev.txBytes,
+ sample.rxBytes-prev.rxBytes)
+ }
+ r.Logger.Printf("blkio:%s %d write %d read%s\n", dev, sample.txBytes, sample.rxBytes, delta)
+ r.lastDiskSample[dev] = sample
+ }
+}
+
+type MemSample struct {
+ sampleTime time.Time
+ memStat map[string]int64
+}
+
+func (r *Reporter) DoMemoryStats() {
+ c, err := r.openStatFile("memory", "memory.stat")
+ if err != nil {
+ return
+ }
+ defer c.Close()
+ b := bufio.NewScanner(c)
+ thisSample := MemSample{time.Now(), make(map[string]int64)}
+ wantStats := [...]string{"cache", "swap", "pgmajfault", "rss"}
+ for b.Scan() {
+ var stat string
+ var val int64
+ if _, err := fmt.Sscanf(string(b.Text()), "%s %d", &stat, &val); err != nil {
+ continue
+ }
+ thisSample.memStat[stat] = val
+ }
+ var outstat bytes.Buffer
+ for _, key := range wantStats {
+ if val, ok := thisSample.memStat[key]; ok {
+ outstat.WriteString(fmt.Sprintf(" %d %s", val, key))
+ }
+ }
+ r.Logger.Printf("mem%s\n", outstat.String())
+}
+
+func (r *Reporter) DoNetworkStats() {
+ sampleTime := time.Now()
+ stats, err := r.getContainerNetStats()
+ if err != nil {
+ return
+ }
+
+ scanner := bufio.NewScanner(stats)
+ for scanner.Scan() {
+ var ifName string
+ var rx, tx int64
+ words := strings.Fields(scanner.Text())
+ if len(words) != 17 {
+ // Skip lines with wrong format
+ continue
+ }
+ ifName = strings.TrimRight(words[0], ":")
+ if ifName == "lo" || ifName == "" {
+ // Skip loopback interface and lines with wrong format
+ continue
+ }
+ if tx, err = strconv.ParseInt(words[9], 10, 64); err != nil {
+ continue
+ }
+ if rx, err = strconv.ParseInt(words[1], 10, 64); err != nil {
+ continue
+ }
+ nextSample := IoSample{}
+ nextSample.sampleTime = sampleTime
+ nextSample.txBytes = tx
+ nextSample.rxBytes = rx
+ var delta string
+ if prev, ok := r.lastNetSample[ifName]; ok {
+ interval := nextSample.sampleTime.Sub(prev.sampleTime).Seconds()
+ delta = fmt.Sprintf(" -- interval %.4f seconds %d tx %d rx",
+ interval,
+ tx-prev.txBytes,
+ rx-prev.rxBytes)
+ }
+ r.Logger.Printf("net:%s %d tx %d rx%s\n", ifName, tx, rx, delta)
+ r.lastNetSample[ifName] = nextSample
+ }
+}
+
+type CpuSample struct {
+ hasData bool // to distinguish the zero value from real data
+ sampleTime time.Time
+ user float64
+ sys float64
+ cpus int64
+}
+
+// Return the number of CPUs available in the container. Return 0 if
+// we can't figure out the real number of CPUs.
+func (r *Reporter) GetCpuCount() int64 {
+ cpusetFile, err := r.openStatFile("cpuset", "cpuset.cpus")
+ if err != nil {
+ return 0
+ }
+ defer cpusetFile.Close()
+ b, err := r.readAllOrWarn(cpusetFile)
+ sp := strings.Split(string(b), ",")
+ cpus := int64(0)
+ 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
+ }
+ }
+ return cpus
+}
+
+func (r *Reporter) DoCpuStats() {
+ statFile, err := r.openStatFile("cpuacct", "cpuacct.stat")
+ if err != nil {
+ return
+ }
+ defer statFile.Close()
+ b, err := r.readAllOrWarn(statFile)
+ if err != nil {
+ return
+ }
+
+ nextSample := CpuSample{true, time.Now(), 0, 0, r.GetCpuCount()}
+ var userTicks, sysTicks int64
+ fmt.Sscanf(string(b), "user %d\nsystem %d", &userTicks, &sysTicks)
+ user_hz := float64(C.sysconf(C._SC_CLK_TCK))
+ nextSample.user = float64(userTicks) / user_hz
+ nextSample.sys = float64(sysTicks) / user_hz
+
+ delta := ""
+ if r.lastCPUSample.hasData {
+ delta = fmt.Sprintf(" -- interval %.4f seconds %.4f user %.4f sys",
+ nextSample.sampleTime.Sub(r.lastCPUSample.sampleTime).Seconds(),
+ nextSample.user-r.lastCPUSample.user,
+ nextSample.sys-r.lastCPUSample.sys)
+ }
+ r.Logger.Printf("cpu %.4f user %.4f sys %d cpus%s\n",
+ nextSample.user, nextSample.sys, nextSample.cpus, delta)
+ r.lastCPUSample = nextSample
+}
+
+// Report stats periodically until someone closes or sends to r.done.
+func (r *Reporter) run() {
+ if !r.waitForCIDFile() {
+ return
+ }
+
+ r.reportedStatFile = make(map[string]string)
+ r.lastNetSample = make(map[string]IoSample)
+ r.lastDiskSample = make(map[string]IoSample)
+
+ ticker := time.NewTicker(r.Poll)
+ for {
+ r.DoMemoryStats()
+ r.DoCpuStats()
+ r.DoBlkIoStats()
+ r.DoNetworkStats()
+ select {
+ case <-r.done:
+ return
+ case <-ticker.C:
+ }
+ }
+}
+
+// If CID is empty, wait for it to appear in CIDFile. Return true if
+// we get it before someone calls Stop().
+func (r *Reporter) waitForCIDFile() bool {
+ if r.CID != "" {
+ return true
+ }
+
+ ticker := time.NewTicker(100 * time.Millisecond)
+ defer ticker.Stop()
+ for {
+ cid, err := ioutil.ReadFile(r.CIDFile)
+ if err == nil && len(cid) > 0 {
+ r.CID = string(cid)
+ return true
+ }
+ select {
+ case <-ticker.C:
+ case <-r.done:
+ r.Logger.Printf("CID never appeared in %+q: %v", r.CIDFile, err)
+ return false
+ }
+ }
+}
import (
"bufio"
- "bytes"
- "errors"
"flag"
- "fmt"
"io"
- "io/ioutil"
"log"
"os"
"os/exec"
"os/signal"
- "strconv"
- "strings"
"syscall"
"time"
-)
-/*
-#include <unistd.h>
-#include <sys/types.h>
-#include <pwd.h>
-#include <stdlib.h>
-*/
-import "C"
+ "git.curoverse.com/arvados.git/lib/crunchstat"
+)
-// The above block of magic allows us to look up user_hz via _SC_CLK_TCK.
+const MaxLogLine = 1 << 14 // Child stderr lines >16KiB will be split
-type Cgroup struct {
- root string
- parent string
- cid string
-}
+func main() {
+ reporter := crunchstat.Reporter{
+ Logger: log.New(os.Stderr, "crunchstat: ", 0),
+ }
-var childLog = log.New(os.Stderr, "", 0)
-var statLog = log.New(os.Stderr, "crunchstat: ", 0)
+ 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")
+ pollMsec := flag.Int64("poll", 1000, "Reporting interval, in milliseconds")
-const (
- MaxLogLine = 1 << 14 // Child stderr lines >16KiB will be split
-)
+ flag.Parse()
-func CopyPipeToChildLog(in io.ReadCloser, done chan<- bool) {
- reader := bufio.NewReaderSize(in, MaxLogLine)
- var prefix string
- for {
- line, isPrefix, err := reader.ReadLine()
- if err == io.EOF {
- break
- } else if err != nil {
- statLog.Fatal("error reading child stderr:", err)
- }
- var suffix string
- if isPrefix {
- suffix = "[...]"
- }
- childLog.Print(prefix, string(line), suffix)
- // Set up prefix for following line
- if isPrefix {
- prefix = "[...]"
- } else {
- prefix = ""
- }
+ if reporter.CgroupRoot == "" {
+ reporter.Logger.Fatal("error: must provide -cgroup-root")
}
- done <- true
- in.Close()
-}
+ reporter.Poll = time.Duration(*pollMsec) * time.Millisecond
-func ReadAllOrWarn(in *os.File) ([]byte, error) {
- content, err := ioutil.ReadAll(in)
- if err != nil {
- statLog.Printf("error reading %s: %s\n", in.Name(), err)
- }
- return content, err
-}
+ reporter.Start()
+ err := runCommand(flag.Args(), reporter.Logger)
+ reporter.Stop()
-var reportedStatFile = map[string]string{}
+ if err, ok := err.(*exec.ExitError); ok {
+ // The program has exited with an exit code != 0
-// Open the cgroup stats file in /sys/fs corresponding to the target
-// cgroup, and return an *os.File. If no stats file is available,
-// return nil.
-//
-// TODO: Instead of trying all options, choose a process in the
-// container, and read /proc/PID/cgroup to determine the appropriate
-// cgroup root for the given statgroup. (This will avoid falling back
-// to host-level stats during container setup and teardown.)
-func OpenStatFile(cgroup Cgroup, statgroup string, stat string) (*os.File, error) {
- var paths []string
- if cgroup.cid != "" {
- // Collect container's stats
- paths = []string{
- fmt.Sprintf("%s/%s/%s/%s/%s", cgroup.root, statgroup, cgroup.parent, cgroup.cid, stat),
- fmt.Sprintf("%s/%s/%s/%s", cgroup.root, cgroup.parent, cgroup.cid, stat),
- }
- } else {
- // Collect this host's stats
- paths = []string{
- fmt.Sprintf("%s/%s/%s", cgroup.root, statgroup, stat),
- fmt.Sprintf("%s/%s", cgroup.root, stat),
- }
- }
- var path string
- var file *os.File
- var err error
- for _, path = range paths {
- file, err = os.Open(path)
- if err == nil {
- break
+ // 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 {
- path = ""
+ reporter.Logger.Fatalln("ExitError without WaitStatus:", err)
}
+ } else if err != nil {
+ reporter.Logger.Fatalln("error in cmd.Wait:", err)
}
- if pathWas, ok := reportedStatFile[stat]; !ok || pathWas != path {
- // Log whenever we start using a new/different cgroup
- // stat file for a given statistic. This typically
- // happens 1 to 3 times per statistic, depending on
- // whether we happen to collect stats [a] before any
- // processes have been created in the container and
- // [b] after all contained processes have exited.
- if path == "" {
- statLog.Printf("notice: stats not available: stat %s, statgroup %s, cid %s, parent %s, root %s\n", stat, statgroup, cgroup.cid, cgroup.parent, cgroup.root)
- } else if ok {
- statLog.Printf("notice: stats moved from %s to %s\n", reportedStatFile[stat], path)
- } else {
- statLog.Printf("notice: reading stats from %s\n", path)
- }
- reportedStatFile[stat] = path
- }
- return file, err
}
-func GetContainerNetStats(cgroup Cgroup) (io.Reader, error) {
- procsFile, err := OpenStatFile(cgroup, "cpuacct", "cgroup.procs")
- if err != nil {
- return nil, err
- }
- defer procsFile.Close()
- reader := bufio.NewScanner(procsFile)
- for reader.Scan() {
- taskPid := reader.Text()
- statsFilename := fmt.Sprintf("/proc/%s/net/dev", taskPid)
- stats, err := ioutil.ReadFile(statsFilename)
- if err != nil {
- statLog.Printf("error reading %s: %s\n", statsFilename, err)
- continue
- }
- return strings.NewReader(string(stats)), nil
- }
- return nil, errors.New("Could not read stats for any proc in container")
-}
+func runCommand(argv []string, logger *log.Logger) error {
+ cmd := exec.Command(argv[0], argv[1:]...)
-type IoSample struct {
- sampleTime time.Time
- txBytes int64
- rxBytes int64
-}
+ logger.Println("Running", argv)
-func DoBlkIoStats(cgroup Cgroup, lastSample map[string]IoSample) {
- c, err := OpenStatFile(cgroup, "blkio", "blkio.io_service_bytes")
- if err != nil {
- return
- }
- defer c.Close()
- b := bufio.NewScanner(c)
- var sampleTime = time.Now()
- newSamples := make(map[string]IoSample)
- for b.Scan() {
- var device, op string
- var val int64
- if _, err := fmt.Sscanf(string(b.Text()), "%s %s %d", &device, &op, &val); err != nil {
- continue
- }
- var thisSample IoSample
- var ok bool
- if thisSample, ok = newSamples[device]; !ok {
- thisSample = IoSample{sampleTime, -1, -1}
- }
- switch op {
- case "Read":
- thisSample.rxBytes = val
- case "Write":
- thisSample.txBytes = val
- }
- newSamples[device] = thisSample
- }
- for dev, sample := range newSamples {
- if sample.txBytes < 0 || sample.rxBytes < 0 {
- continue
- }
- delta := ""
- if prev, ok := lastSample[dev]; ok {
- delta = fmt.Sprintf(" -- interval %.4f seconds %d write %d read",
- sample.sampleTime.Sub(prev.sampleTime).Seconds(),
- sample.txBytes-prev.txBytes,
- sample.rxBytes-prev.rxBytes)
- }
- statLog.Printf("blkio:%s %d write %d read%s\n", dev, sample.txBytes, sample.rxBytes, delta)
- lastSample[dev] = sample
- }
-}
-
-type MemSample struct {
- sampleTime time.Time
- memStat map[string]int64
-}
+ // Child process will use our stdin and stdout pipes
+ // (we close our copies below)
+ cmd.Stdin = os.Stdin
+ cmd.Stdout = os.Stdout
-func DoMemoryStats(cgroup Cgroup) {
- c, err := OpenStatFile(cgroup, "memory", "memory.stat")
- if err != nil {
- return
- }
- defer c.Close()
- b := bufio.NewScanner(c)
- thisSample := MemSample{time.Now(), make(map[string]int64)}
- wantStats := [...]string{"cache", "swap", "pgmajfault", "rss"}
- for b.Scan() {
- var stat string
- var val int64
- if _, err := fmt.Sscanf(string(b.Text()), "%s %d", &stat, &val); err != nil {
- continue
- }
- thisSample.memStat[stat] = val
- }
- var outstat bytes.Buffer
- for _, key := range wantStats {
- if val, ok := thisSample.memStat[key]; ok {
- outstat.WriteString(fmt.Sprintf(" %d %s", val, key))
+ // 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)
}
- }
- statLog.Printf("mem%s\n", outstat.String())
-}
+ logger.Println("notice: caught signal:", catch)
+ }(sigChan)
+ signal.Notify(sigChan, syscall.SIGTERM)
+ signal.Notify(sigChan, syscall.SIGINT)
-func DoNetworkStats(cgroup Cgroup, lastSample map[string]IoSample) {
- sampleTime := time.Now()
- stats, err := GetContainerNetStats(cgroup)
+ // Funnel stderr through our channel
+ stderr_pipe, err := cmd.StderrPipe()
if err != nil {
- return
+ logger.Fatalln("error in StderrPipe:", err)
}
- scanner := bufio.NewScanner(stats)
- for scanner.Scan() {
- var ifName string
- var rx, tx int64
- words := strings.Fields(scanner.Text())
- if len(words) != 17 {
- // Skip lines with wrong format
- continue
- }
- ifName = strings.TrimRight(words[0], ":")
- if ifName == "lo" || ifName == "" {
- // Skip loopback interface and lines with wrong format
- continue
- }
- if tx, err = strconv.ParseInt(words[9], 10, 64); err != nil {
- continue
- }
- if rx, err = strconv.ParseInt(words[1], 10, 64); err != nil {
- continue
- }
- nextSample := IoSample{}
- nextSample.sampleTime = sampleTime
- nextSample.txBytes = tx
- nextSample.rxBytes = rx
- var delta string
- if prev, ok := lastSample[ifName]; ok {
- interval := nextSample.sampleTime.Sub(prev.sampleTime).Seconds()
- delta = fmt.Sprintf(" -- interval %.4f seconds %d tx %d rx",
- interval,
- tx-prev.txBytes,
- rx-prev.rxBytes)
- }
- statLog.Printf("net:%s %d tx %d rx%s\n", ifName, tx, rx, delta)
- lastSample[ifName] = nextSample
+ // Run subprocess
+ if err := cmd.Start(); err != nil {
+ logger.Fatalln("error in cmd.Start:", err)
}
-}
-type CpuSample struct {
- hasData bool // to distinguish the zero value from real data
- sampleTime time.Time
- user float64
- sys float64
- cpus int64
-}
+ // Close stdin/stdout in this (parent) process
+ os.Stdin.Close()
+ os.Stdout.Close()
-// Return the number of CPUs available in the container. Return 0 if
-// we can't figure out the real number of CPUs.
-func GetCpuCount(cgroup Cgroup) int64 {
- cpusetFile, err := OpenStatFile(cgroup, "cpuset", "cpuset.cpus")
- if err != nil {
- return 0
- }
- defer cpusetFile.Close()
- b, err := ReadAllOrWarn(cpusetFile)
- sp := strings.Split(string(b), ",")
- cpus := int64(0)
- 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
- }
- }
- return cpus
-}
+ copyPipeToChildLog(stderr_pipe, log.New(os.Stderr, "", 0))
-func DoCpuStats(cgroup Cgroup, lastSample *CpuSample) {
- statFile, err := OpenStatFile(cgroup, "cpuacct", "cpuacct.stat")
- if err != nil {
- return
- }
- defer statFile.Close()
- b, err := ReadAllOrWarn(statFile)
- if err != nil {
- return
- }
-
- nextSample := CpuSample{true, time.Now(), 0, 0, GetCpuCount(cgroup)}
- var userTicks, sysTicks int64
- fmt.Sscanf(string(b), "user %d\nsystem %d", &userTicks, &sysTicks)
- user_hz := float64(C.sysconf(C._SC_CLK_TCK))
- nextSample.user = float64(userTicks) / user_hz
- nextSample.sys = float64(sysTicks) / user_hz
-
- delta := ""
- if lastSample.hasData {
- delta = fmt.Sprintf(" -- interval %.4f seconds %.4f user %.4f sys",
- nextSample.sampleTime.Sub(lastSample.sampleTime).Seconds(),
- nextSample.user-lastSample.user,
- nextSample.sys-lastSample.sys)
- }
- statLog.Printf("cpu %.4f user %.4f sys %d cpus%s\n",
- nextSample.user, nextSample.sys, nextSample.cpus, delta)
- *lastSample = nextSample
+ return cmd.Wait()
}
-func PollCgroupStats(cgroup Cgroup, poll int64, stop_poll_chan <-chan bool) {
- var lastNetSample = map[string]IoSample{}
- var lastDiskSample = map[string]IoSample{}
- var lastCpuSample = CpuSample{}
-
- 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
- }
- }()
+func copyPipeToChildLog(in io.ReadCloser, logger *log.Logger) {
+ reader := bufio.NewReaderSize(in, MaxLogLine)
+ var prefix string
for {
- select {
- case <-stop_poll_chan:
- return
- case <-poll_chan:
- // Emit stats, then select again.
- }
- DoMemoryStats(cgroup)
- DoCpuStats(cgroup, &lastCpuSample)
- DoBlkIoStats(cgroup, lastDiskSample)
- DoNetworkStats(cgroup, lastNetSample)
- }
-}
-
-func run(logger *log.Logger) error {
-
- var (
- cgroup_root string
- cgroup_parent string
- cgroup_cidfile string
- wait int64
- poll int64
- )
-
- 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")
-
- flag.Parse()
-
- if cgroup_root == "" {
- statLog.Fatal("error: must provide -cgroup-root")
- }
-
- finish_chan := make(chan bool)
- defer close(finish_chan)
-
- var cmd *exec.Cmd
-
- if len(flag.Args()) > 0 {
- // Set up subprocess
- cmd = exec.Command(flag.Args()[0], flag.Args()[1:]...)
-
- childLog.Println("Running", flag.Args())
-
- // Child process will use our stdin and stdout pipes
- // (we close our copies below)
- cmd.Stdin = os.Stdin
- cmd.Stdout = os.Stdout
-
- // Forward SIGINT and SIGTERM to inner process
- sigChan := make(chan os.Signal, 1)
- go func(sig <-chan os.Signal) {
- catch := <-sig
- if cmd.Process != nil {
- cmd.Process.Signal(catch)
- }
- statLog.Println("notice: caught signal:", catch)
- }(sigChan)
- signal.Notify(sigChan, syscall.SIGTERM)
- signal.Notify(sigChan, syscall.SIGINT)
-
- // Funnel stderr through our channel
- stderr_pipe, err := cmd.StderrPipe()
- if err != nil {
- statLog.Fatalln("error in StderrPipe:", err)
- }
- go CopyPipeToChildLog(stderr_pipe, finish_chan)
-
- // Run subprocess
- if err := cmd.Start(); err != nil {
- statLog.Fatalln("error in cmd.Start:", err)
- }
-
- // 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 := ioutil.ReadFile(cgroup_cidfile)
- if err == nil && len(cid) > 0 {
- ok = true
- container_id = string(cid)
- break
- }
- time.Sleep(100 * time.Millisecond)
+ line, isPrefix, err := reader.ReadLine()
+ if err == io.EOF {
+ break
+ } else if err != nil {
+ logger.Fatal("error reading child stderr:", err)
}
- if !ok {
- statLog.Println("error reading cid file:", cgroup_cidfile)
+ var suffix string
+ if isPrefix {
+ suffix = "[...]"
}
- }
-
- stop_poll_chan := make(chan bool, 1)
- cgroup := Cgroup{cgroup_root, cgroup_parent, container_id}
- go PollCgroupStats(cgroup, 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())
- }
+ logger.Print(prefix, string(line), suffix)
+ // Set up prefix for following line
+ if isPrefix {
+ prefix = "[...]"
} else {
- statLog.Fatalln("error in cmd.Wait:", err)
+ prefix = ""
}
}
+ in.Close()
}
"io"
"log"
"math/rand"
- "os"
- "regexp"
"testing"
"time"
)
-func TestReadAllOrWarnFail(t *testing.T) {
- rcv := captureLogs()
- defer uncaptureLogs()
- go func() {
- // The special file /proc/self/mem can be opened for
- // reading, but reading from byte 0 returns an error.
- f, err := os.Open("/proc/self/mem")
- if err != nil {
- t.Fatalf("Opening /proc/self/mem: %s", err)
- }
- if x, err := ReadAllOrWarn(f); err == nil {
- t.Fatalf("Expected error, got %v", x)
- }
- }()
- if msg, err := rcv.ReadBytes('\n'); err != nil {
- t.Fatal(err)
- } else if matched, err := regexp.MatchString("^crunchstat: .*error.*", string(msg)); err != nil || !matched {
- t.Fatalf("Expected error message about unreadable file, got \"%s\"", msg)
- }
-}
-
-func TestReadAllOrWarnSuccess(t *testing.T) {
- f, err := os.Open("./crunchstat_test.go")
- if err != nil {
- t.Fatalf("Opening ./crunchstat_test.go: %s", err)
- }
- data, err := ReadAllOrWarn(f)
- if err != nil {
- t.Fatalf("got error %s", err)
- }
- if matched, err := regexp.MatchString("^package main\n", string(data)); err != nil || !matched {
- t.Fatalf("data failed regexp: %s", err)
- }
-}
-
// Test that CopyPipeToChildLog works even on lines longer than
// bufio.MaxScanTokenSize.
func TestCopyPipeToChildLogLongLines(t *testing.T) {
- rcv := captureLogs()
- defer uncaptureLogs()
+ logger, logBuf := bufLogger()
- control := make(chan bool)
pipeIn, pipeOut := io.Pipe()
- go CopyPipeToChildLog(pipeIn, control)
+ copied := make(chan bool)
+ go func() {
+ copyPipeToChildLog(pipeIn, logger)
+ close(copied)
+ }()
sentBytes := make([]byte, bufio.MaxScanTokenSize+MaxLogLine+(1<<22))
go func() {
pipeOut.Close()
}()
- if before, err := rcv.ReadBytes('\n'); err != nil || string(before) != "before\n" {
+ if before, err := logBuf.ReadBytes('\n'); err != nil || string(before) != "before\n" {
t.Fatalf("\"before\n\" not received (got \"%s\", %s)", before, err)
}
var receivedBytes []byte
done := false
for !done {
- line, err := rcv.ReadBytes('\n')
+ line, err := logBuf.ReadBytes('\n')
if err != nil {
t.Fatal(err)
}
t.Fatalf("sent %d bytes, got %d different bytes", len(sentBytes), len(receivedBytes))
}
- if after, err := rcv.ReadBytes('\n'); err != nil || string(after) != "after\n" {
+ if after, err := logBuf.ReadBytes('\n'); err != nil || string(after) != "after\n" {
t.Fatalf("\"after\n\" not received (got \"%s\", %s)", after, err)
}
select {
case <-time.After(time.Second):
t.Fatal("Timeout")
- case <-control:
+ case <-copied:
// Done.
}
}
-func captureLogs() *bufio.Reader {
- // Send childLog to our bufio reader instead of stderr
- stderrIn, stderrOut := io.Pipe()
- childLog = log.New(stderrOut, "", 0)
- statLog = log.New(stderrOut, "crunchstat: ", 0)
- return bufio.NewReader(stderrIn)
-}
-
-func uncaptureLogs() {
- childLog = log.New(os.Stderr, "", 0)
- statLog = log.New(os.Stderr, "crunchstat: ", 0)
+func bufLogger() (*log.Logger, *bufio.Reader) {
+ r, w := io.Pipe()
+ logger := log.New(w, "", 0)
+ return logger, bufio.NewReader(r)
}
projects / arvados.git / commitdiff