func (h Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
ctx := route.Context(r)
name := strings.Trim(route.Param(ctx, "filepath"), "/")
if name == "" {
name = "index.html"
}
file, err := GetFile(StaticFiles, name)
if err != nil {
if err != io.EOF {
log.Warn("Could not get file: ", err)
}
w.WriteHeader(http.StatusNotFound)
return
}
contentType := http.DetectContentType(file)
if strings.Contains(contentType, "text/plain") || strings.Contains(contentType, "application/octet-stream") {
parts := strings.Split(name, ".")
contentType = mimeMap[parts[len(parts)-1]]
}
w.Header().Set("Content-Type", contentType)
w.Header().Set("Cache-Control", "public, max-age=259200")
w.Write(file)
}
// Collect implements prometheus.Collector.
func (c *viewCollector) Collect(ch chan<- prometheus.Metric) {
for _, v := range c.stats.Views {
for _, s := range v.Cache {
ch <- prometheus.MustNewConstMetric(
resolverCache, prometheus.GaugeValue, float64(s.Gauge), v.Name, s.Name,
)
}
for _, s := range v.ResolverQueries {
ch <- prometheus.MustNewConstMetric(
resolverQueries, prometheus.CounterValue, float64(s.Counter), v.Name, s.Name,
)
}
for _, s := range v.ResolverStats {
if desc, ok := resolverMetricStats[s.Name]; ok {
ch <- prometheus.MustNewConstMetric(
desc, prometheus.CounterValue, float64(s.Counter), v.Name,
)
}
if desc, ok := resolverLabelStats[s.Name]; ok {
ch <- prometheus.MustNewConstMetric(
desc, prometheus.CounterValue, float64(s.Counter), v.Name, s.Name,
)
}
}
if buckets, count, err := histogram(v.ResolverStats); err == nil {
ch <- prometheus.MustNewConstHistogram(
resolverQueryDuration, count, math.NaN(), buckets, v.Name,
)
} else {
log.Warn("Error parsing RTT:", err)
}
}
}
// loadSeriesMapAndHeads loads the fingerprint to memory-series mapping and all
// the chunks contained in the checkpoint (and thus not yet persisted to series
// files). The method is capable of loading the checkpoint format v1 and v2. If
// recoverable corruption is detected, or if the dirty flag was set from the
// beginning, crash recovery is run, which might take a while. If an
// unrecoverable error is encountered, it is returned. Call this method during
// start-up while nothing else is running in storage land. This method is
// utterly goroutine-unsafe.
func (p *persistence) loadSeriesMapAndHeads() (sm *seriesMap, chunksToPersist int64, err error) {
fingerprintToSeries := make(map[model.Fingerprint]*memorySeries)
sm = &seriesMap{m: fingerprintToSeries}
defer func() {
if p.dirty {
log.Warn("Persistence layer appears dirty.")
p.startedDirty.Set(1)
err = p.recoverFromCrash(fingerprintToSeries)
if err != nil {
sm = nil
}
} else {
p.startedDirty.Set(0)
}
}()
hs := newHeadsScanner(p.headsFileName())
defer hs.close()
for hs.scan() {
fingerprintToSeries[hs.fp] = hs.series
}
if os.IsNotExist(hs.err) {
return sm, 0, nil
}
if hs.err != nil {
p.dirty = true
log.
With("file", p.headsFileName()).
With("error", hs.err).
Error("Error reading heads file.")
return sm, 0, hs.err
}
return sm, hs.chunksToPersistTotal, nil
}
// Append queues a sample to be sent to the remote storage. It drops the
// sample on the floor if the queue is full. It implements
// storage.SampleAppender.
func (t *StorageQueueManager) Append(s *model.Sample) {
select {
case t.queue <- s:
default:
t.samplesCount.WithLabelValues(dropped).Inc()
log.Warn("Remote storage queue full, discarding sample.")
}
}
// Append queues a sample to be sent to the remote storage. It drops the
// sample on the floor if the queue is full.
// Always returns nil.
func (t *StorageQueueManager) Append(s *model.Sample) error {
fp := s.Metric.FastFingerprint()
shard := uint64(fp) % uint64(t.cfg.Shards)
select {
case t.shards[shard] <- s:
default:
t.sentSamplesTotal.WithLabelValues(dropped).Inc()
log.Warn("Remote storage queue full, discarding sample.")
}
return nil
}
// Append implements Storage.
func (s *memorySeriesStorage) Append(sample *model.Sample) {
for ln, lv := range sample.Metric {
if len(lv) == 0 {
delete(sample.Metric, ln)
}
}
if s.getNumChunksToPersist() >= s.maxChunksToPersist {
log.Warnf(
"%d chunks waiting for persistence, sample ingestion suspended.",
s.getNumChunksToPersist(),
)
for s.getNumChunksToPersist() >= s.maxChunksToPersist {
time.Sleep(time.Second)
}
log.Warn("Sample ingestion resumed.")
}
rawFP := sample.Metric.FastFingerprint()
s.fpLocker.Lock(rawFP)
fp, err := s.mapper.mapFP(rawFP, sample.Metric)
if err != nil {
log.Errorf("Error while mapping fingerprint %v: %v", rawFP, err)
s.persistence.setDirty(true)
}
if fp != rawFP {
// Switch locks.
s.fpLocker.Unlock(rawFP)
s.fpLocker.Lock(fp)
}
series := s.getOrCreateSeries(fp, sample.Metric)
if sample.Timestamp <= series.lastTime {
// Don't log and track equal timestamps, as they are a common occurrence
// when using client-side timestamps (e.g. Pushgateway or federation).
// It would be even better to also compare the sample values here, but
// we don't have efficient access to a series's last value.
if sample.Timestamp != series.lastTime {
log.Warnf("Ignoring sample with out-of-order timestamp for fingerprint %v (%v): %v is not after %v", fp, series.metric, sample.Timestamp, series.lastTime)
s.outOfOrderSamplesCount.Inc()
}
s.fpLocker.Unlock(fp)
return
}
completedChunksCount := series.add(&model.SamplePair{
Value: sample.Value,
Timestamp: sample.Timestamp,
})
s.fpLocker.Unlock(fp)
s.ingestedSamplesCount.Inc()
s.incNumChunksToPersist(completedChunksCount)
}
// isDegraded returns whether the storage is in "graceful degradation mode",
// which is the case if the number of chunks waiting for persistence has reached
// a percentage of maxChunksToPersist that exceeds
// percentChunksToPersistForDegradation. The method is not goroutine safe (but
// only ever called from the goroutine dealing with series maintenance).
// Changes of degradation mode are logged.
func (s *memorySeriesStorage) isDegraded() bool {
nowDegraded := s.getNumChunksToPersist() > s.maxChunksToPersist*percentChunksToPersistForDegradation/100
if s.degraded && !nowDegraded {
log.Warn("Storage has left graceful degradation mode. Things are back to normal.")
} else if !s.degraded && nowDegraded {
log.Warnf(
"%d chunks waiting for persistence (%d%% of the allowed maximum %d). Storage is now in graceful degradation mode. Series files are not synced anymore if following the adaptive strategy. Checkpoints are not performed more often than every %v. Series maintenance happens as frequently as possible.",
s.getNumChunksToPersist(),
s.getNumChunksToPersist()*100/s.maxChunksToPersist,
s.maxChunksToPersist,
s.checkpointInterval)
}
s.degraded = nowDegraded
return s.degraded
}
func serveAsset(w http.ResponseWriter, req *http.Request, fp string) {
info, err := ui.AssetInfo(fp)
if err != nil {
log.Warn("Could not get file: ", err)
w.WriteHeader(http.StatusNotFound)
return
}
file, err := ui.Asset(fp)
if err != nil {
if err != io.EOF {
log.With("file", fp).Warn("Could not get file: ", err)
}
w.WriteHeader(http.StatusNotFound)
return
}
http.ServeContent(w, req, info.Name(), info.ModTime(), bytes.NewReader(file))
}
// Run dispatches notifications continuously.
func (n *NotificationHandler) Run() {
for reqs := range n.pendingNotifications {
if n.alertmanagerURL == "" {
log.Warn("No alert manager configured, not dispatching notification")
n.notificationDropped.Inc()
continue
}
begin := time.Now()
err := n.sendNotifications(reqs)
if err != nil {
log.Error("Error sending notification: ", err)
n.notificationErrors.Inc()
}
n.notificationLatency.Observe(float64(time.Since(begin) / time.Millisecond))
}
close(n.stopped)
}
// Main manages the startup and shutdown lifecycle of the entire Prometheus server.
func Main() int {
if err := parse(os.Args[1:]); err != nil {
return 2
}
printVersion()
if cfg.printVersion {
return 0
}
var reloadables []Reloadable
var (
memStorage = local.NewMemorySeriesStorage(&cfg.storage)
remoteStorage = remote.New(&cfg.remote)
sampleAppender = storage.Fanout{memStorage}
)
if remoteStorage != nil {
sampleAppender = append(sampleAppender, remoteStorage)
reloadables = append(reloadables, remoteStorage)
}
var (
notificationHandler = notification.New(&cfg.notification)
targetManager = retrieval.NewTargetManager(sampleAppender)
queryEngine = promql.NewEngine(memStorage, &cfg.queryEngine)
)
ruleManager := rules.NewManager(&rules.ManagerOptions{
SampleAppender: sampleAppender,
NotificationHandler: notificationHandler,
QueryEngine: queryEngine,
ExternalURL: cfg.web.ExternalURL,
})
flags := map[string]string{}
cfg.fs.VisitAll(func(f *flag.Flag) {
flags[f.Name] = f.Value.String()
})
status := &web.PrometheusStatus{
TargetPools: targetManager.Pools,
Rules: ruleManager.Rules,
Flags: flags,
Birth: time.Now(),
}
webHandler := web.New(memStorage, queryEngine, ruleManager, status, &cfg.web)
reloadables = append(reloadables, status, targetManager, ruleManager, webHandler, notificationHandler)
if !reloadConfig(cfg.configFile, reloadables...) {
return 1
}
// Wait for reload or termination signals. Start the handler for SIGHUP as
// early as possible, but ignore it until we are ready to handle reloading
// our config.
hup := make(chan os.Signal)
hupReady := make(chan bool)
signal.Notify(hup, syscall.SIGHUP)
go func() {
<-hupReady
for {
select {
case <-hup:
case <-webHandler.Reload():
}
reloadConfig(cfg.configFile, reloadables...)
}
}()
// Start all components.
if err := memStorage.Start(); err != nil {
log.Errorln("Error opening memory series storage:", err)
return 1
}
defer func() {
if err := memStorage.Stop(); err != nil {
log.Errorln("Error stopping storage:", err)
}
}()
if remoteStorage != nil {
prometheus.MustRegister(remoteStorage)
go remoteStorage.Run()
defer remoteStorage.Stop()
}
// The storage has to be fully initialized before registering.
prometheus.MustRegister(memStorage)
prometheus.MustRegister(notificationHandler)
prometheus.MustRegister(configSuccess)
prometheus.MustRegister(configSuccessTime)
defer ruleManager.Stop()
go notificationHandler.Run()
defer notificationHandler.Stop()
go targetManager.Run()
defer targetManager.Stop()
defer queryEngine.Stop()
go webHandler.Run()
// Wait for reload or termination signals.
close(hupReady) // Unblock SIGHUP handler.
term := make(chan os.Signal)
signal.Notify(term, os.Interrupt, syscall.SIGTERM)
select {
case <-term:
log.Warn("Received SIGTERM, exiting gracefully...")
case <-webHandler.Quit():
log.Warn("Received termination request via web service, exiting gracefully...")
case err := <-webHandler.ListenError():
log.Errorln("Error starting web server, exiting gracefully:", err)
}
log.Info("See you next time!")
return 0
}
// Main manages the startup and shutdown lifecycle of the entire Prometheus server.
func Main() int {
if err := parse(os.Args[1:]); err != nil {
log.Error(err)
return 2
}
if cfg.printVersion {
fmt.Fprintln(os.Stdout, version.Print("prometheus"))
return 0
}
log.Infoln("Starting prometheus", version.Info())
log.Infoln("Build context", version.BuildContext())
var reloadables []Reloadable
var (
memStorage = local.NewMemorySeriesStorage(&cfg.storage)
remoteStorage = remote.New(&cfg.remote)
sampleAppender = storage.Fanout{memStorage}
)
if remoteStorage != nil {
sampleAppender = append(sampleAppender, remoteStorage)
reloadables = append(reloadables, remoteStorage)
}
var (
notifier = notifier.New(&cfg.notifier)
targetManager = retrieval.NewTargetManager(sampleAppender)
queryEngine = promql.NewEngine(memStorage, &cfg.queryEngine)
)
ruleManager := rules.NewManager(&rules.ManagerOptions{
SampleAppender: sampleAppender,
Notifier: notifier,
QueryEngine: queryEngine,
ExternalURL: cfg.web.ExternalURL,
})
flags := map[string]string{}
cfg.fs.VisitAll(func(f *flag.Flag) {
flags[f.Name] = f.Value.String()
})
version := &web.PrometheusVersion{
Version: version.Version,
Revision: version.Revision,
Branch: version.Branch,
BuildUser: version.BuildUser,
BuildDate: version.BuildDate,
GoVersion: version.GoVersion,
}
webHandler := web.New(memStorage, queryEngine, targetManager, ruleManager, version, flags, &cfg.web)
reloadables = append(reloadables, targetManager, ruleManager, webHandler, notifier)
if !reloadConfig(cfg.configFile, reloadables...) {
return 1
}
// Wait for reload or termination signals. Start the handler for SIGHUP as
// early as possible, but ignore it until we are ready to handle reloading
// our config.
hup := make(chan os.Signal)
hupReady := make(chan bool)
signal.Notify(hup, syscall.SIGHUP)
go func() {
<-hupReady
for {
select {
case <-hup:
case <-webHandler.Reload():
}
reloadConfig(cfg.configFile, reloadables...)
}
}()
// Start all components. The order is NOT arbitrary.
if err := memStorage.Start(); err != nil {
log.Errorln("Error opening memory series storage:", err)
return 1
}
defer func() {
if err := memStorage.Stop(); err != nil {
log.Errorln("Error stopping storage:", err)
}
}()
if remoteStorage != nil {
prometheus.MustRegister(remoteStorage)
go remoteStorage.Run()
defer remoteStorage.Stop()
}
// The storage has to be fully initialized before registering.
prometheus.MustRegister(memStorage)
prometheus.MustRegister(notifier)
prometheus.MustRegister(configSuccess)
prometheus.MustRegister(configSuccessTime)
// The notifieris a dependency of the rule manager. It has to be
// started before and torn down afterwards.
go notifier.Run()
defer notifier.Stop()
go ruleManager.Run()
defer ruleManager.Stop()
go targetManager.Run()
defer targetManager.Stop()
// Shutting down the query engine before the rule manager will cause pending queries
// to be canceled and ensures a quick shutdown of the rule manager.
defer queryEngine.Stop()
go webHandler.Run()
// Wait for reload or termination signals.
close(hupReady) // Unblock SIGHUP handler.
term := make(chan os.Signal)
signal.Notify(term, os.Interrupt, syscall.SIGTERM)
select {
case <-term:
log.Warn("Received SIGTERM, exiting gracefully...")
case <-webHandler.Quit():
log.Warn("Received termination request via web service, exiting gracefully...")
case err := <-webHandler.ListenError():
log.Errorln("Error starting web server, exiting gracefully:", err)
}
log.Info("See you next time!")
return 0
}
// recoverFromCrash is called by loadSeriesMapAndHeads if the persistence
// appears to be dirty after the loading (either because the loading resulted in
// an error or because the persistence was dirty from the start). Not goroutine
// safe. Only call before anything else is running (except index processing
// queue as started by newPersistence).
func (p *persistence) recoverFromCrash(fingerprintToSeries map[model.Fingerprint]*memorySeries) error {
// TODO(beorn): We need proper tests for the crash recovery.
log.Warn("Starting crash recovery. Prometheus is inoperational until complete.")
log.Warn("To avoid crash recovery in the future, shut down Prometheus with SIGTERM or a HTTP POST to /-/quit.")
fpsSeen := map[model.Fingerprint]struct{}{}
count := 0
seriesDirNameFmt := fmt.Sprintf("%%0%dx", seriesDirNameLen)
// Delete the fingerprint mapping file as it might be stale or
// corrupt. We'll rebuild the mappings as we go.
if err := os.RemoveAll(p.mappingsFileName()); err != nil {
return fmt.Errorf("couldn't remove old fingerprint mapping file %s: %s", p.mappingsFileName(), err)
}
// The mappings to rebuild.
fpm := fpMappings{}
log.Info("Scanning files.")
for i := 0; i < 1<<(seriesDirNameLen*4); i++ {
dirname := filepath.Join(p.basePath, fmt.Sprintf(seriesDirNameFmt, i))
dir, err := os.Open(dirname)
if os.IsNotExist(err) {
continue
}
if err != nil {
return err
}
for fis := []os.FileInfo{}; err != io.EOF; fis, err = dir.Readdir(1024) {
if err != nil {
dir.Close()
return err
}
for _, fi := range fis {
fp, ok := p.sanitizeSeries(dirname, fi, fingerprintToSeries, fpm)
if ok {
fpsSeen[fp] = struct{}{}
}
count++
if count%10000 == 0 {
log.Infof("%d files scanned.", count)
}
}
}
dir.Close()
}
log.Infof("File scan complete. %d series found.", len(fpsSeen))
log.Info("Checking for series without series file.")
for fp, s := range fingerprintToSeries {
if _, seen := fpsSeen[fp]; !seen {
// fp exists in fingerprintToSeries, but has no representation on disk.
if s.persistWatermark == len(s.chunkDescs) {
// Oops, everything including the head chunk was
// already persisted, but nothing on disk.
// Thus, we lost that series completely. Clean
// up the remnants.
delete(fingerprintToSeries, fp)
if err := p.purgeArchivedMetric(fp); err != nil {
// Purging the archived metric didn't work, so try
// to unindex it, just in case it's in the indexes.
p.unindexMetric(fp, s.metric)
}
log.Warnf("Lost series detected: fingerprint %v, metric %v.", fp, s.metric)
continue
}
// If we are here, the only chunks we have are the chunks in the checkpoint.
// Adjust things accordingly.
if s.persistWatermark > 0 || s.chunkDescsOffset != 0 {
minLostChunks := s.persistWatermark + s.chunkDescsOffset
if minLostChunks <= 0 {
log.Warnf(
"Possible loss of chunks for fingerprint %v, metric %v.",
fp, s.metric,
)
} else {
log.Warnf(
"Lost at least %d chunks for fingerprint %v, metric %v.",
minLostChunks, fp, s.metric,
)
}
s.chunkDescs = append(
make([]*chunk.Desc, 0, len(s.chunkDescs)-s.persistWatermark),
s.chunkDescs[s.persistWatermark:]...,
)
chunk.NumMemDescs.Sub(float64(s.persistWatermark))
s.persistWatermark = 0
s.chunkDescsOffset = 0
}
maybeAddMapping(fp, s.metric, fpm)
fpsSeen[fp] = struct{}{} // Add so that fpsSeen is complete.
}
}
log.Info("Check for series without series file complete.")
if err := p.cleanUpArchiveIndexes(fingerprintToSeries, fpsSeen, fpm); err != nil {
return err
}
if err := p.rebuildLabelIndexes(fingerprintToSeries); err != nil {
return err
}
// Finally rewrite the mappings file if there are any mappings.
if len(fpm) > 0 {
if err := p.checkpointFPMappings(fpm); err != nil {
return err
}
}
p.dirtyMtx.Lock()
// Only declare storage clean if it didn't become dirty during crash recovery.
if !p.becameDirty {
p.dirty = false
}
p.dirtyMtx.Unlock()
log.Warn("Crash recovery complete.")
return nil
}
// Main manages the startup and shutdown lifecycle of the entire Prometheus server.
func Main() int {
if err := parse(os.Args[1:]); err != nil {
log.Error(err)
return 2
}
if cfg.printVersion {
fmt.Fprintln(os.Stdout, version.Print("prometheus"))
return 0
}
log.Infoln("Starting prometheus", version.Info())
log.Infoln("Build context", version.BuildContext())
var (
sampleAppender = storage.Fanout{}
reloadables []Reloadable
)
var localStorage local.Storage
switch cfg.localStorageEngine {
case "persisted":
localStorage = local.NewMemorySeriesStorage(&cfg.storage)
sampleAppender = storage.Fanout{localStorage}
case "none":
localStorage = &local.NoopStorage{}
default:
log.Errorf("Invalid local storage engine %q", cfg.localStorageEngine)
return 1
}
remoteStorage, err := remote.New(&cfg.remote)
if err != nil {
log.Errorf("Error initializing remote storage: %s", err)
return 1
}
if remoteStorage != nil {
sampleAppender = append(sampleAppender, remoteStorage)
reloadables = append(reloadables, remoteStorage)
}
reloadableRemoteStorage := remote.NewConfigurable()
sampleAppender = append(sampleAppender, reloadableRemoteStorage)
reloadables = append(reloadables, reloadableRemoteStorage)
var (
notifier = notifier.New(&cfg.notifier)
targetManager = retrieval.NewTargetManager(sampleAppender)
queryEngine = promql.NewEngine(localStorage, &cfg.queryEngine)
ctx, cancelCtx = context.WithCancel(context.Background())
)
ruleManager := rules.NewManager(&rules.ManagerOptions{
SampleAppender: sampleAppender,
Notifier: notifier,
QueryEngine: queryEngine,
Context: ctx,
ExternalURL: cfg.web.ExternalURL,
})
cfg.web.Context = ctx
cfg.web.Storage = localStorage
cfg.web.QueryEngine = queryEngine
cfg.web.TargetManager = targetManager
cfg.web.RuleManager = ruleManager
cfg.web.Version = &web.PrometheusVersion{
Version: version.Version,
Revision: version.Revision,
Branch: version.Branch,
BuildUser: version.BuildUser,
BuildDate: version.BuildDate,
GoVersion: version.GoVersion,
}
cfg.web.Flags = map[string]string{}
cfg.fs.VisitAll(func(f *flag.Flag) {
cfg.web.Flags[f.Name] = f.Value.String()
})
webHandler := web.New(&cfg.web)
reloadables = append(reloadables, targetManager, ruleManager, webHandler, notifier)
if err := reloadConfig(cfg.configFile, reloadables...); err != nil {
log.Errorf("Error loading config: %s", err)
return 1
}
// Wait for reload or termination signals. Start the handler for SIGHUP as
// early as possible, but ignore it until we are ready to handle reloading
// our config.
hup := make(chan os.Signal)
hupReady := make(chan bool)
signal.Notify(hup, syscall.SIGHUP)
go func() {
<-hupReady
for {
select {
case <-hup:
if err := reloadConfig(cfg.configFile, reloadables...); err != nil {
log.Errorf("Error reloading config: %s", err)
}
case rc := <-webHandler.Reload():
if err := reloadConfig(cfg.configFile, reloadables...); err != nil {
log.Errorf("Error reloading config: %s", err)
rc <- err
} else {
rc <- nil
}
}
}
}()
// Start all components. The order is NOT arbitrary.
if err := localStorage.Start(); err != nil {
log.Errorln("Error opening memory series storage:", err)
return 1
}
defer func() {
if err := localStorage.Stop(); err != nil {
log.Errorln("Error stopping storage:", err)
}
}()
if remoteStorage != nil {
remoteStorage.Start()
defer remoteStorage.Stop()
}
defer reloadableRemoteStorage.Stop()
// The storage has to be fully initialized before registering.
if instrumentedStorage, ok := localStorage.(prometheus.Collector); ok {
prometheus.MustRegister(instrumentedStorage)
}
prometheus.MustRegister(notifier)
prometheus.MustRegister(configSuccess)
prometheus.MustRegister(configSuccessTime)
// The notifier is a dependency of the rule manager. It has to be
// started before and torn down afterwards.
go notifier.Run()
defer notifier.Stop()
go ruleManager.Run()
defer ruleManager.Stop()
go targetManager.Run()
defer targetManager.Stop()
// Shutting down the query engine before the rule manager will cause pending queries
// to be canceled and ensures a quick shutdown of the rule manager.
defer cancelCtx()
go webHandler.Run()
// Wait for reload or termination signals.
close(hupReady) // Unblock SIGHUP handler.
term := make(chan os.Signal)
signal.Notify(term, os.Interrupt, syscall.SIGTERM)
select {
case <-term:
log.Warn("Received SIGTERM, exiting gracefully...")
case <-webHandler.Quit():
log.Warn("Received termination request via web service, exiting gracefully...")
case err := <-webHandler.ListenError():
log.Errorln("Error starting web server, exiting gracefully:", err)
}
log.Info("See you next time!")
return 0
}
// loadSeriesMapAndHeads loads the fingerprint to memory-series mapping and all
// the chunks contained in the checkpoint (and thus not yet persisted to series
// files). The method is capable of loading the checkpoint format v1 and v2. If
// recoverable corruption is detected, or if the dirty flag was set from the
// beginning, crash recovery is run, which might take a while. If an
// unrecoverable error is encountered, it is returned. Call this method during
// start-up while nothing else is running in storage land. This method is
// utterly goroutine-unsafe.
func (p *persistence) loadSeriesMapAndHeads() (sm *seriesMap, chunksToPersist int64, err error) {
var chunkDescsTotal int64
fingerprintToSeries := make(map[model.Fingerprint]*memorySeries)
sm = &seriesMap{m: fingerprintToSeries}
defer func() {
if sm != nil && p.dirty {
log.Warn("Persistence layer appears dirty.")
err = p.recoverFromCrash(fingerprintToSeries)
if err != nil {
sm = nil
}
}
if err == nil {
numMemChunkDescs.Add(float64(chunkDescsTotal))
}
}()
f, err := os.Open(p.headsFileName())
if os.IsNotExist(err) {
return sm, 0, nil
}
if err != nil {
log.Warn("Could not open heads file:", err)
p.dirty = true
return
}
defer f.Close()
r := bufio.NewReaderSize(f, fileBufSize)
buf := make([]byte, len(headsMagicString))
if _, err := io.ReadFull(r, buf); err != nil {
log.Warn("Could not read from heads file:", err)
p.dirty = true
return sm, 0, nil
}
magic := string(buf)
if magic != headsMagicString {
log.Warnf(
"unexpected magic string, want %q, got %q",
headsMagicString, magic,
)
p.dirty = true
return
}
version, err := binary.ReadVarint(r)
if (version != headsFormatVersion && version != headsFormatLegacyVersion) || err != nil {
log.Warnf("unknown heads format version, want %d", headsFormatVersion)
p.dirty = true
return sm, 0, nil
}
numSeries, err := codable.DecodeUint64(r)
if err != nil {
log.Warn("Could not decode number of series:", err)
p.dirty = true
return sm, 0, nil
}
for ; numSeries > 0; numSeries-- {
seriesFlags, err := r.ReadByte()
if err != nil {
log.Warn("Could not read series flags:", err)
p.dirty = true
return sm, chunksToPersist, nil
}
headChunkPersisted := seriesFlags&flagHeadChunkPersisted != 0
fp, err := codable.DecodeUint64(r)
if err != nil {
log.Warn("Could not decode fingerprint:", err)
p.dirty = true
return sm, chunksToPersist, nil
}
var metric codable.Metric
if err := metric.UnmarshalFromReader(r); err != nil {
log.Warn("Could not decode metric:", err)
p.dirty = true
return sm, chunksToPersist, nil
}
var persistWatermark int64
var modTime time.Time
if version != headsFormatLegacyVersion {
// persistWatermark only present in v2.
persistWatermark, err = binary.ReadVarint(r)
if err != nil {
log.Warn("Could not decode persist watermark:", err)
p.dirty = true
return sm, chunksToPersist, nil
}
modTimeNano, err := binary.ReadVarint(r)
if err != nil {
log.Warn("Could not decode modification time:", err)
p.dirty = true
return sm, chunksToPersist, nil
}
if modTimeNano != -1 {
modTime = time.Unix(0, modTimeNano)
}
}
chunkDescsOffset, err := binary.ReadVarint(r)
if err != nil {
log.Warn("Could not decode chunk descriptor offset:", err)
p.dirty = true
return sm, chunksToPersist, nil
}
savedFirstTime, err := binary.ReadVarint(r)
if err != nil {
log.Warn("Could not decode saved first time:", err)
p.dirty = true
return sm, chunksToPersist, nil
}
numChunkDescs, err := binary.ReadVarint(r)
if err != nil {
log.Warn("Could not decode number of chunk descriptors:", err)
p.dirty = true
return sm, chunksToPersist, nil
}
chunkDescs := make([]*chunkDesc, numChunkDescs)
if version == headsFormatLegacyVersion {
if headChunkPersisted {
persistWatermark = numChunkDescs
} else {
persistWatermark = numChunkDescs - 1
}
}
for i := int64(0); i < numChunkDescs; i++ {
if i < persistWatermark {
firstTime, err := binary.ReadVarint(r)
if err != nil {
log.Warn("Could not decode first time:", err)
p.dirty = true
return sm, chunksToPersist, nil
}
lastTime, err := binary.ReadVarint(r)
if err != nil {
log.Warn("Could not decode last time:", err)
p.dirty = true
return sm, chunksToPersist, nil
}
chunkDescs[i] = &chunkDesc{
chunkFirstTime: model.Time(firstTime),
chunkLastTime: model.Time(lastTime),
}
chunkDescsTotal++
} else {
// Non-persisted chunk.
encoding, err := r.ReadByte()
if err != nil {
log.Warn("Could not decode chunk type:", err)
p.dirty = true
return sm, chunksToPersist, nil
}
chunk := newChunkForEncoding(chunkEncoding(encoding))
if err := chunk.unmarshal(r); err != nil {
log.Warn("Could not decode chunk:", err)
p.dirty = true
return sm, chunksToPersist, nil
}
chunkDescs[i] = newChunkDesc(chunk)
chunksToPersist++
}
}
fingerprintToSeries[model.Fingerprint(fp)] = &memorySeries{
metric: model.Metric(metric),
chunkDescs: chunkDescs,
persistWatermark: int(persistWatermark),
modTime: modTime,
chunkDescsOffset: int(chunkDescsOffset),
savedFirstTime: model.Time(savedFirstTime),
lastTime: chunkDescs[len(chunkDescs)-1].lastTime(),
headChunkClosed: persistWatermark >= numChunkDescs,
}
}
return sm, chunksToPersist, nil
}