"fmt"
"io"
"io/ioutil"
- "log"
"os"
+ "regexp"
+ "sort"
"strconv"
"strings"
+ "sync"
"syscall"
"time"
)
+// crunchstat collects all memory statistics, but only reports these.
+var memoryStats = [...]string{"cache", "swap", "pgmajfault", "rss"}
+
+type logPrinter interface {
+ Printf(fmt string, args ...interface{})
+}
+
// A Reporter gathers statistics for a cgroup and writes them to a
// log.Logger.
type Reporter struct {
TempDir string
// Where to write statistics. Must not be nil.
- Logger *log.Logger
+ Logger logPrinter
+
+ // When stats cross thresholds configured in the fields below,
+ // they are reported to this logger.
+ ThresholdLogger logPrinter
+
+ // MemThresholds maps memory stat names to slices of thresholds.
+ // When the corresponding stat exceeds a threshold, that will be logged.
+ MemThresholds map[string][]Threshold
+ kernelPageSize int64
reportedStatFile map[string]string
lastNetSample map[string]ioSample
lastDiskIOSample map[string]ioSample
lastCPUSample cpuSample
lastDiskSpaceSample diskSpaceSample
+ lastMemSample memSample
+ maxDiskSpaceSample diskSpaceSample
+ maxMemSample map[memoryKey]int64
+
+ reportPIDs map[string]int
+ reportPIDsMu sync.Mutex
done chan struct{} // closed when we should stop reporting
flushed chan struct{} // closed when we have made our last report
}
+type Threshold struct {
+ percentage int64
+ threshold int64
+ total int64
+}
+
+func NewThresholdFromPercentage(total int64, percentage int64) Threshold {
+ return Threshold{
+ percentage: percentage,
+ threshold: total * percentage / 100,
+ total: total,
+ }
+}
+
+func NewThresholdsFromPercentages(total int64, percentages []int64) (thresholds []Threshold) {
+ for _, percentage := range percentages {
+ thresholds = append(thresholds, NewThresholdFromPercentage(total, percentage))
+ }
+ return
+}
+
+// memoryKey is a key into Reporter.maxMemSample.
+// Initialize it with just statName to get the host/cgroup maximum.
+// Initialize it with all fields to get that process' maximum.
+type memoryKey struct {
+ processID int
+ processName string
+ statName string
+}
+
// Start starts monitoring in a new goroutine, and returns
// immediately.
//
go r.run()
}
+// ReportPID starts reporting stats for a specified process.
+func (r *Reporter) ReportPID(name string, pid int) {
+ r.reportPIDsMu.Lock()
+ defer r.reportPIDsMu.Unlock()
+ if r.reportPIDs == nil {
+ r.reportPIDs = map[string]int{name: pid}
+ } else {
+ r.reportPIDs[name] = pid
+ }
+}
+
// Stop reporting. Do not call more than once, or before calling
// Start.
//
-// Nothing will be logged after Stop returns.
+// Nothing will be logged after Stop returns unless you call a Log* method.
func (r *Reporter) Stop() {
close(r.done)
<-r.flushed
}
+func (r *Reporter) reportMemoryMax(logger logPrinter, source, statName string, value, limit int64) {
+ var units string
+ switch statName {
+ case "pgmajfault":
+ units = "faults"
+ default:
+ units = "bytes"
+ }
+ if limit > 0 {
+ percentage := 100 * value / limit
+ logger.Printf("Maximum %s memory %s usage was %d%%, %d/%d %s",
+ source, statName, percentage, value, limit, units)
+ } else {
+ logger.Printf("Maximum %s memory %s usage was %d %s",
+ source, statName, value, units)
+ }
+}
+
+func (r *Reporter) LogMaxima(logger logPrinter, memLimits map[string]int64) {
+ if r.lastCPUSample.hasData {
+ logger.Printf("Total CPU usage was %f user and %f sys on %d CPUs",
+ r.lastCPUSample.user, r.lastCPUSample.sys, r.lastCPUSample.cpus)
+ }
+ for disk, sample := range r.lastDiskIOSample {
+ logger.Printf("Total disk I/O on %s was %d bytes written and %d bytes read",
+ disk, sample.txBytes, sample.rxBytes)
+ }
+ if r.maxDiskSpaceSample.total > 0 {
+ percentage := 100 * r.maxDiskSpaceSample.used / r.maxDiskSpaceSample.total
+ logger.Printf("Maximum disk usage was %d%%, %d/%d bytes",
+ percentage, r.maxDiskSpaceSample.used, r.maxDiskSpaceSample.total)
+ }
+ for _, statName := range memoryStats {
+ value, ok := r.maxMemSample[memoryKey{statName: "total_" + statName}]
+ if !ok {
+ value, ok = r.maxMemSample[memoryKey{statName: statName}]
+ }
+ if ok {
+ r.reportMemoryMax(logger, "container", statName, value, memLimits[statName])
+ }
+ }
+ for ifname, sample := range r.lastNetSample {
+ logger.Printf("Total network I/O on %s was %d bytes written and %d bytes read",
+ ifname, sample.txBytes, sample.rxBytes)
+ }
+}
+
+func (r *Reporter) LogProcessMemMax(logger logPrinter) {
+ for memKey, value := range r.maxMemSample {
+ if memKey.processName == "" {
+ continue
+ }
+ r.reportMemoryMax(logger, memKey.processName, memKey.statName, value, 0)
+ }
+}
+
func (r *Reporter) readAllOrWarn(in io.Reader) ([]byte, error) {
content, err := ioutil.ReadAll(in)
if err != nil {
memStat map[string]int64
}
-func (r *Reporter) doMemoryStats() {
+func (r *Reporter) getMemSample() {
c, err := r.openStatFile("memory", "memory.stat", true)
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
continue
}
thisSample.memStat[stat] = val
+ maxKey := memoryKey{statName: stat}
+ if val > r.maxMemSample[maxKey] {
+ r.maxMemSample[maxKey] = val
+ }
}
+ r.lastMemSample = thisSample
+
+ if r.ThresholdLogger != nil {
+ for statName, thresholds := range r.MemThresholds {
+ statValue, ok := thisSample.memStat["total_"+statName]
+ if !ok {
+ statValue, ok = thisSample.memStat[statName]
+ if !ok {
+ continue
+ }
+ }
+ var index int
+ var statThreshold Threshold
+ for index, statThreshold = range thresholds {
+ if statValue < statThreshold.threshold {
+ break
+ } else if statThreshold.percentage > 0 {
+ r.ThresholdLogger.Printf("Container using over %d%% of memory (%s %d/%d bytes)",
+ statThreshold.percentage, statName, statValue, statThreshold.total)
+ } else {
+ r.ThresholdLogger.Printf("Container using over %d of memory (%s %s bytes)",
+ statThreshold.threshold, statName, statValue)
+ }
+ }
+ r.MemThresholds[statName] = thresholds[index:]
+ }
+ }
+}
+
+func (r *Reporter) reportMemSample() {
var outstat bytes.Buffer
- for _, key := range wantStats {
+ for _, key := range memoryStats {
// Use "total_X" stats (entire hierarchy) if enabled,
// otherwise just the single cgroup -- see
// https://www.kernel.org/doc/Documentation/cgroup-v1/memory.txt
- if val, ok := thisSample.memStat["total_"+key]; ok {
+ if val, ok := r.lastMemSample.memStat["total_"+key]; ok {
fmt.Fprintf(&outstat, " %d %s", val, key)
- } else if val, ok := thisSample.memStat[key]; ok {
+ } else if val, ok := r.lastMemSample.memStat[key]; ok {
fmt.Fprintf(&outstat, " %d %s", val, key)
}
}
r.Logger.Printf("mem%s\n", outstat.String())
}
+func (r *Reporter) doProcmemStats() {
+ if r.kernelPageSize == 0 {
+ // assign "don't try again" value in case we give up
+ // and return without assigning the real value
+ r.kernelPageSize = -1
+ buf, err := os.ReadFile("/proc/self/smaps")
+ if err != nil {
+ r.Logger.Printf("error reading /proc/self/smaps: %s", err)
+ return
+ }
+ m := regexp.MustCompile(`\nKernelPageSize:\s*(\d+) kB\n`).FindSubmatch(buf)
+ if len(m) != 2 {
+ r.Logger.Printf("error parsing /proc/self/smaps: KernelPageSize not found")
+ return
+ }
+ size, err := strconv.ParseInt(string(m[1]), 10, 64)
+ if err != nil {
+ r.Logger.Printf("error parsing /proc/self/smaps: KernelPageSize %q: %s", m[1], err)
+ return
+ }
+ r.kernelPageSize = size * 1024
+ } else if r.kernelPageSize < 0 {
+ // already failed to determine page size, don't keep
+ // trying/logging
+ return
+ }
+
+ r.reportPIDsMu.Lock()
+ defer r.reportPIDsMu.Unlock()
+ procnames := make([]string, 0, len(r.reportPIDs))
+ for name := range r.reportPIDs {
+ procnames = append(procnames, name)
+ }
+ sort.Strings(procnames)
+ procmem := ""
+ for _, procname := range procnames {
+ pid := r.reportPIDs[procname]
+ buf, err := os.ReadFile(fmt.Sprintf("/proc/%d/stat", pid))
+ if err != nil {
+ continue
+ }
+ // If the executable name contains a ')' char,
+ // /proc/$pid/stat will look like '1234 (exec name)) S
+ // 123 ...' -- the last ')' is the end of the 2nd
+ // field.
+ paren := bytes.LastIndexByte(buf, ')')
+ if paren < 0 {
+ continue
+ }
+ fields := bytes.SplitN(buf[paren:], []byte{' '}, 24)
+ if len(fields) < 24 {
+ continue
+ }
+ // rss is the 24th field in .../stat, and fields[0]
+ // here is the last char ')' of the 2nd field, so
+ // rss is fields[22]
+ rss, err := strconv.ParseInt(string(fields[22]), 10, 64)
+ if err != nil {
+ continue
+ }
+ value := rss * r.kernelPageSize
+ procmem += fmt.Sprintf(" %d %s", value, procname)
+ maxKey := memoryKey{pid, procname, "rss"}
+ if value > r.maxMemSample[maxKey] {
+ r.maxMemSample[maxKey] = value
+ }
+ }
+ if procmem != "" {
+ r.Logger.Printf("procmem%s\n", procmem)
+ }
+}
+
func (r *Reporter) doNetworkStats() {
sampleTime := time.Now()
stats, err := r.getContainerNetStats()
used: (s.Blocks - s.Bfree) * bs,
available: s.Bavail * bs,
}
+ if nextSample.used > r.maxDiskSpaceSample.used {
+ r.maxDiskSpaceSample = nextSample
+ }
var delta string
if r.lastDiskSpaceSample.hasData {
r.lastCPUSample = nextSample
}
+func (r *Reporter) doAllStats() {
+ r.reportMemSample()
+ r.doProcmemStats()
+ r.doCPUStats()
+ r.doBlkIOStats()
+ r.doNetworkStats()
+ r.doDiskSpaceStats()
+}
+
// Report stats periodically until we learn (via r.done) that someone
// called Stop.
func (r *Reporter) run() {
defer close(r.flushed)
+ r.maxMemSample = make(map[memoryKey]int64)
r.reportedStatFile = make(map[string]string)
if !r.waitForCIDFile() || !r.waitForCgroup() {
r.Logger.Printf("notice: monitoring temp dir %s\n", r.TempDir)
}
- ticker := time.NewTicker(r.PollPeriod)
+ r.getMemSample()
+ r.doAllStats()
+
+ memTicker := time.NewTicker(time.Second)
+ mainTicker := time.NewTicker(r.PollPeriod)
for {
- r.doMemoryStats()
- r.doCPUStats()
- r.doBlkIOStats()
- r.doNetworkStats()
- r.doDiskSpaceStats()
select {
case <-r.done:
return
- case <-ticker.C:
+ case <-memTicker.C:
+ r.getMemSample()
+ case <-mainTicker.C:
+ r.doAllStats()
}
}
}
projects / arvados.git / blobdiff