retrieval/storage: adapt to new interface

This simplifies the interface to two add methods for
appends with labels or faster reference numbers.

cmd/prometheus/main.go

@@ -20,7 +20,6 @@ import (
 	_ "net/http/pprof" // Comment this line to disable pprof endpoint.
 	"os"
 	"os/signal"
-	"runtime/trace"
 	"syscall"
 	"time"
 
@@ -61,18 +60,6 @@ func init() {
 
 // Main manages the stup and shutdown lifecycle of the entire Prometheus server.
 func Main() int {
-	go func() {
-		f, err := os.Create("trace")
-		if err != nil {
-			panic(err)
-		}
-		if err := trace.Start(f); err != nil {
-			panic(err)
-		}
-		time.Sleep(30 * time.Second)
-		trace.Stop()
-		f.Close()
-	}()
 	if err := parse(os.Args[1:]); err != nil {
 		log.Error(err)
 		return 2
@@ -91,7 +78,11 @@ func Main() int {
 		reloadables []Reloadable
 	)
 
-	localStorage, err := tsdb.Open(cfg.localStoragePath)
+	localStorage, err := tsdb.Open(cfg.localStoragePath, &tsdb.Options{
+		MinBlockDuration: 2 * 60 * 60 * 1000,
+		MaxBlockDuration: 24 * 60 * 60 * 1000,
+		AppendableBlocks: 2,
+	})
 	if err != nil {
 		log.Errorf("Opening storage failed: %s", err)
 		return 1

promql/test.go

@@ -285,11 +285,7 @@ func (cmd *loadCmd) append(a storage.Appender) error {
 		m := cmd.metrics[h]
 
 		for _, s := range smpls {
-			ref, err := a.SetSeries(m)
-			if err != nil {
-				return err
-			}
-			if err := a.Add(ref, s.T, s.V); err != nil {
+			if _, err := a.Add(m, s.T, s.V); err != nil {
 				return err
 			}
 		}

retrieval/scrape.go

@@ -514,6 +514,7 @@ func (sl *scrapeLoop) append(b []byte, ts time.Time) (total, added int, err erro
 		defTime = timestamp.FromTime(ts)
 	)
 
+loop:
 	for p.Next() {
 		total++
 
@@ -526,33 +527,33 @@ func (sl *scrapeLoop) append(b []byte, ts time.Time) (total, added int, err erro
 		mets := string(met)
 		ref, ok := sl.cache[mets]
 		if ok {
-			if err = app.Add(ref, t, v); err == nil {
-				added++
-				continue
-			} else if err != storage.ErrNotFound {
-				break
-			}
+			switch err = app.AddFast(ref, t, v); err {
+			case nil:
+			case storage.ErrNotFound:
 				ok = false
+			case errSeriesDropped:
+				continue
+			default:
+				break loop
+			}
 		}
 		if !ok {
 			var lset labels.Labels
 			p.Metric(&lset)
 
-			ref, err = app.SetSeries(lset)
+			ref, err = app.Add(lset, t, v)
 			// TODO(fabxc): also add a dropped-cache?
-			if err == errSeriesDropped {
+			switch err {
+			case nil:
+			case errSeriesDropped:
 				continue
-			}
-			if err != nil {
-				break
-			}
-			if err = app.Add(ref, t, v); err != nil {
-				break
-			}
-			added++
+			default:
+				break loop
 			}
 			sl.cache[mets] = ref
 		}
+		added++
+	}
 	if err == nil {
 		err = p.Err()
 	}
@@ -601,20 +602,19 @@ func (sl *scrapeLoop) addReportSample(app storage.Appender, s string, t int64, v
 	ref, ok := sl.cache[s]
 
 	if ok {
-		if err := app.Add(ref, t, v); err != storage.ErrNotFound {
+		if err := app.AddFast(ref, t, v); err == nil {
+			return nil
+		} else if err != storage.ErrNotFound {
 			return err
 		}
 	}
 	met := labels.Labels{
 		labels.Label{Name: labels.MetricName, Value: s},
 	}
-	ref, err := app.SetSeries(met)
+	ref, err := app.Add(met, t, v)
 	if err != nil {
 		return err
 	}
-	if err = app.Add(ref, t, v); err != nil {
-		return err
-	}
 	sl.cache[s] = ref
 
 	return nil

retrieval/target.go

@@ -235,12 +235,24 @@ type limitAppender struct {
 	i     int
 }
 
-func (app *limitAppender) Add(ref uint64, t int64, v float64) error {
+func (app *limitAppender) Add(lset labels.Labels, t int64, v float64) (uint64, error) {
+	if app.i+1 > app.limit {
+		return 0, errors.New("sample limit exceeded")
+	}
+	ref, err := app.Appender.Add(lset, t, v)
+	if err != nil {
+		return 0, fmt.Errorf("sample limit of %d exceeded", app.limit)
+	}
+	app.i++
+	return ref, nil
+}
+
+func (app *limitAppender) AddFast(ref uint64, t int64, v float64) error {
 	if app.i+1 > app.limit {
 		return errors.New("sample limit exceeded")
 	}
 
-	if err := app.Appender.Add(ref, t, v); err != nil {
+	if err := app.Appender.AddFast(ref, t, v); err != nil {
 		return fmt.Errorf("sample limit of %d exceeded", app.limit)
 	}
 	app.i++
@@ -254,7 +266,7 @@ type ruleLabelsAppender struct {
 	labels labels.Labels
 }
 
-func (app ruleLabelsAppender) SetSeries(lset labels.Labels) (uint64, error) {
+func (app ruleLabelsAppender) Add(lset labels.Labels, t int64, v float64) (uint64, error) {
 	lb := labels.NewBuilder(lset)
 
 	for _, l := range app.labels {
@@ -265,7 +277,7 @@ func (app ruleLabelsAppender) SetSeries(lset labels.Labels) (uint64, error) {
 		lb.Set(l.Name, l.Value)
 	}
 
-	return app.Appender.SetSeries(lb.Labels())
+	return app.Appender.Add(lb.Labels(), t, v)
 }
 
 type honorLabelsAppender struct {
@@ -276,7 +288,7 @@ type honorLabelsAppender struct {
 // Merges the sample's metric with the given labels if the label is not
 // already present in the metric.
 // This also considers labels explicitly set to the empty string.
-func (app honorLabelsAppender) SetSeries(lset labels.Labels) (uint64, error) {
+func (app honorLabelsAppender) Add(lset labels.Labels, t int64, v float64) (uint64, error) {
 	lb := labels.NewBuilder(lset)
 
 	for _, l := range app.labels {
@@ -284,7 +296,7 @@ func (app honorLabelsAppender) SetSeries(lset labels.Labels) (uint64, error) {
 			lb.Set(l.Name, l.Value)
 		}
 	}
-	return app.Appender.SetSeries(lb.Labels())
+	return app.Appender.Add(lb.Labels(), t, v)
 }
 
 // Applies a set of relabel configurations to the sample's metric
@@ -296,12 +308,12 @@ type relabelAppender struct {
 
 var errSeriesDropped = errors.New("series dropped")
 
-func (app relabelAppender) SetSeries(lset labels.Labels) (uint64, error) {
+func (app relabelAppender) Add(lset labels.Labels, t int64, v float64) (uint64, error) {
 	lset = relabel.Process(lset, app.relabelings...)
 	if lset == nil {
 		return 0, errSeriesDropped
 	}
-	return app.Appender.SetSeries(lset)
+	return app.Appender.Add(lset, t, v)
 }
 
 // populateLabels builds a label set from the given label set and scrape configuration.

rules/manager.go

@@ -282,21 +282,16 @@ func (g *Group) Eval() {
 			}
 
 			for _, s := range vector {
-				ref, err := app.SetSeries(s.Metric)
-				if err != nil {
-					log.With("sample", s).With("error", err).Warn("Setting metric failed")
-					continue
-				}
-				if err := app.Add(ref, s.T, s.V); err != nil {
+				if _, err := app.Add(s.Metric, s.T, s.V); err != nil {
 					switch err {
 					case storage.ErrOutOfOrderSample:
 						numOutOfOrder++
-						log.With("sample", s).With("error", err).Debug("Rule evaluation result discarded")
+						log.With("sample", s).With("err", err).Debug("Rule evaluation result discarded")
 					case storage.ErrDuplicateSampleForTimestamp:
 						numDuplicates++
-						log.With("sample", s).With("error", err).Debug("Rule evaluation result discarded")
+						log.With("sample", s).With("err", err).Debug("Rule evaluation result discarded")
 					default:
-						log.With("sample", s).With("error", err).Warn("Rule evaluation result discarded")
+						log.With("sample", s).With("err", err).Warn("Rule evaluation result discarded")
 					}
 				}
 			}

storage/interface.go

@@ -52,10 +52,9 @@ type Querier interface {
 
 // Appender provides batched appends against a storage.
 type Appender interface {
-	SetSeries(labels.Labels) (uint64, error)
+	Add(l labels.Labels, t int64, v float64) (uint64, error)
 
-	// Add adds a sample pair for the referenced series.
-	Add(ref uint64, t int64, v float64) error
+	AddFast(ref uint64, t int64, v float64) error
 
 	// Commit submits the collected samples and purges the batch.
 	Commit() error

storage/tsdb/tsdb.go

@@ -1,6 +1,7 @@
 package tsdb
 
 import (
+	"time"
 	"unsafe"
 
 	"github.com/fabxc/tsdb"
@@ -14,9 +15,34 @@ type adapter struct {
 	db *tsdb.PartitionedDB
 }
 
+// Options of the DB storage.
+type Options struct {
+	// The interval at which the write ahead log is flushed to disc.
+	WALFlushInterval time.Duration
+
+	// The timestamp range of head blocks after which they get persisted.
+	// It's the minimum duration of any persisted block.
+	MinBlockDuration uint64
+
+	// The maximum timestamp range of compacted blocks.
+	MaxBlockDuration uint64
+
+	// Number of head blocks that can be appended to.
+	// Should be two or higher to prevent write errors in general scenarios.
+	//
+	// After a new block is started for timestamp t0 or higher, appends with
+	// timestamps as early as t0 - (n-1) * MinBlockDuration are valid.
+	AppendableBlocks int
+}
+
 // Open returns a new storage backed by a tsdb database.
-func Open(path string) (storage.Storage, error) {
-	db, err := tsdb.OpenPartitioned(path, 1, nil, nil)
+func Open(path string, opts *Options) (storage.Storage, error) {
+	db, err := tsdb.OpenPartitioned(path, 1, nil, &tsdb.Options{
+		WALFlushInterval: 10 * time.Second,
+		MinBlockDuration: opts.MinBlockDuration,
+		MaxBlockDuration: opts.MaxBlockDuration,
+		AppendableBlocks: opts.AppendableBlocks,
+	})
 	if err != nil {
 		return nil, err
 	}
@@ -73,12 +99,22 @@ type appender struct {
 	a tsdb.Appender
 }
 
-func (a appender) SetSeries(lset labels.Labels) (uint64, error) {
-	return a.a.SetSeries(toTSDBLabels(lset))
+func (a appender) Add(lset labels.Labels, t int64, v float64) (uint64, error) {
+	ref, err := a.a.Add(toTSDBLabels(lset), t, v)
+
+	switch err {
+	case tsdb.ErrNotFound:
+		return 0, storage.ErrNotFound
+	case tsdb.ErrOutOfOrderSample:
+		return 0, storage.ErrOutOfOrderSample
+	case tsdb.ErrAmendSample:
+		return 0, storage.ErrDuplicateSampleForTimestamp
+	}
+	return ref, err
 }
 
-func (a appender) Add(ref uint64, t int64, v float64) error {
-	err := a.a.Add(ref, t, v)
+func (a appender) AddFast(ref uint64, t int64, v float64) error {
+	err := a.a.AddFast(ref, t, v)
 
 	switch err {
 	case tsdb.ErrNotFound:

util/testutil/storage.go

@@ -19,7 +19,11 @@ func NewStorage(t T) storage.Storage {
 
 	log.With("dir", dir).Debugln("opening test storage")
 
-	db, err := tsdb.Open(dir)
+	db, err := tsdb.Open(dir, &tsdb.Options{
+		MinBlockDuration: 2 * 60 * 60 * 1000,
+		MaxBlockDuration: 24 * 60 * 60 * 1000,
+		AppendableBlocks: 10,
+	})
 	if err != nil {
 		t.Fatalf("Opening test storage failed: %s", err)
 	}