Merge pull request #348 from prometheus/refactor/storage/componentize

Replace direct curation table access with wrapper.

storage/metric/curator.go

@@ -64,7 +64,7 @@ type Curator struct {
 // forward until the stop point or end of the series is reached.
 type watermarkScanner struct {
 	// curationState is the data store for curation remarks.
-	curationState raw.Persistence
+	curationState CurationRemarker
 	// diskFrontier models the available seekable ranges for the provided
 	// sampleIterator.
 	diskFrontier *diskFrontier
@@ -92,7 +92,7 @@ type watermarkScanner struct {
 // curated.
 // curationState is the on-disk store where the curation remarks are made for
 // how much progress has been made.
-func (c *Curator) Run(ignoreYoungerThan time.Duration, instant time.Time, processor Processor, curationState, samples *leveldb.LevelDBPersistence, watermarks HighWatermarker, status chan CurationState) (err error) {
+func (c *Curator) Run(ignoreYoungerThan time.Duration, instant time.Time, processor Processor, curationState CurationRemarker, samples *leveldb.LevelDBPersistence, watermarks HighWatermarker, status chan CurationState) (err error) {
 	defer func(t time.Time) {
 		duration := float64(time.Since(t) / time.Millisecond)
 
@@ -189,26 +189,6 @@ func (w *watermarkScanner) shouldStop() bool {
 	return len(w.stop) != 0
 }
 
-func (w *watermarkScanner) getCurationRemark(k *curationKey) (r *curationRemark, found bool, err error) {
-	curationKey := new(dto.CurationKey)
-	curationValue := new(dto.CurationValue)
-
-	k.dump(curationKey)
-
-	present, err := w.curationState.Get(curationKey, curationValue)
-	if err != nil {
-		return nil, false, err
-	}
-	if !present {
-		return nil, false, nil
-	}
-
-	remark := new(curationRemark)
-	remark.load(curationValue)
-
-	return remark, true, nil
-}
-
 func (w *watermarkScanner) Filter(key, value interface{}) (r storage.FilterResult) {
 	fingerprint := key.(*clientmodel.Fingerprint)
 
@@ -244,18 +224,18 @@ func (w *watermarkScanner) Filter(key, value interface{}) (r storage.FilterResul
 		IgnoreYoungerThan:        w.ignoreYoungerThan,
 	}
 
-	curationRemark, present, err := w.getCurationRemark(k)
+	curationRemark, present, err := w.curationState.Get(k)
 	if err != nil {
 		return
 	}
 	if !present {
 		return storage.ACCEPT
 	}
-	if !curationRemark.OlderThan(w.stopAt) {
+	if !curationRemark.Before(w.stopAt) {
 		return storage.SKIP
 	}
 	watermark := value.(*watermarks)
-	if !curationRemark.OlderThan(watermark.High) {
+	if !curationRemark.Before(watermark.High) {
 		return storage.SKIP
 	}
 	curationConsistent, err := w.curationConsistent(fingerprint, watermark)
@@ -278,14 +258,14 @@ func (w *watermarkScanner) curationConsistent(f *clientmodel.Fingerprint, waterm
 		ProcessorMessageTypeName: w.processor.Name(),
 		IgnoreYoungerThan:        w.ignoreYoungerThan,
 	}
-	curationRemark, present, err := w.getCurationRemark(k)
+	curationRemark, present, err := w.curationState.Get(k)
 	if err != nil {
 		return false, err
 	}
 	if !present {
 		return false, nil
 	}
-	if !curationRemark.OlderThan(watermark.High) {
+	if !curationRemark.Before(watermark.High) {
 		return true, nil
 	}
 
@@ -303,14 +283,13 @@ func (w *watermarkScanner) Operate(key, _ interface{}) (oErr *storage.OperatorEr
 		return &storage.OperatorError{error: err, Continuable: false}
 	}
 
-	k := &curationKey{
+	curationState, present, err := w.curationState.Get(&curationKey{
 		Fingerprint:              fingerprint,
 		ProcessorMessageRaw:      w.processor.Signature(),
 		ProcessorMessageTypeName: w.processor.Name(),
 		IgnoreYoungerThan:        w.ignoreYoungerThan,
-	}
+	})
 
-	curationState, _, err := w.getCurationRemark(k)
 	if err != nil {
 		// An anomaly with the curation remark is likely not fatal in the sense that
 		// there was a decoding error with the entity and shouldn't be cause to stop
@@ -318,10 +297,19 @@ func (w *watermarkScanner) Operate(key, _ interface{}) (oErr *storage.OperatorEr
 		// work forward.  With an idempotent processor, this is safe.
 		return &storage.OperatorError{error: err, Continuable: true}
 	}
+	var firstSeek time.Time
+	switch {
+	case !present, seriesFrontier.After(curationState):
+		firstSeek = seriesFrontier.firstSupertime
+	case !seriesFrontier.InSafeSeekRange(curationState):
+		firstSeek = seriesFrontier.lastSupertime
+	default:
+		firstSeek = curationState
+	}
 
 	startKey := &SampleKey{
 		Fingerprint:    fingerprint,
-		FirstTimestamp: seriesFrontier.optimalStartTime(curationState),
+		FirstTimestamp: firstSeek,
 	}
 	dto := new(dto.SampleKey)
 
@@ -345,7 +333,12 @@ func (w *watermarkScanner) Operate(key, _ interface{}) (oErr *storage.OperatorEr
 		return &storage.OperatorError{error: err, Continuable: false}
 	}
 
-	err = w.refreshCurationRemark(fingerprint, lastTime)
+	err = w.curationState.Update(&curationKey{
+		Fingerprint:              fingerprint,
+		ProcessorMessageRaw:      w.processor.Signature(),
+		ProcessorMessageTypeName: w.processor.Name(),
+		IgnoreYoungerThan:        w.ignoreYoungerThan,
+	}, lastTime)
 	if err != nil {
 		// Under the assumption that the processors are idempotent, they can be
 		// re-run; thusly, the commitment of the curation remark is no cause
@@ -353,56 +346,7 @@ func (w *watermarkScanner) Operate(key, _ interface{}) (oErr *storage.OperatorEr
 		return &storage.OperatorError{error: err, Continuable: true}
 	}
 
-	return
+	return nil
-}
-
-func (w *watermarkScanner) refreshCurationRemark(f *clientmodel.Fingerprint, finished time.Time) error {
-	curationKey := curationKey{
-		Fingerprint:              f,
-		ProcessorMessageRaw:      w.processor.Signature(),
-		ProcessorMessageTypeName: w.processor.Name(),
-		IgnoreYoungerThan:        w.ignoreYoungerThan,
-	}
-	k := new(dto.CurationKey)
-	curationKey.dump(k)
-	curationValue := curationRemark{
-		LastCompletionTimestamp: finished,
-	}
-	v := new(dto.CurationValue)
-	curationValue.dump(v)
-
-	return w.curationState.Put(k, v)
-}
-
-// curationRemark provides a representation of dto.CurationValue with associated
-// business logic methods attached to it to enhance code readability.
-type curationRemark struct {
-	LastCompletionTimestamp time.Time
-}
-
-// OlderThan answers whether this curationRemark is older than the provided
-// cutOff time.
-func (c *curationRemark) OlderThan(t time.Time) bool {
-	return c.LastCompletionTimestamp.Before(t)
-}
-
-// Equal answers whether the two curationRemarks are equivalent.
-func (c *curationRemark) Equal(o curationRemark) bool {
-	return c.LastCompletionTimestamp.Equal(o.LastCompletionTimestamp)
-}
-
-func (c *curationRemark) String() string {
-	return fmt.Sprintf("Last curated at %s", c.LastCompletionTimestamp)
-}
-
-func (c *curationRemark) load(d *dto.CurationValue) {
-	c.LastCompletionTimestamp = time.Unix(d.GetLastCompletionTimestamp(), 0).UTC()
-}
-
-func (c *curationRemark) dump(d *dto.CurationValue) {
-	d.Reset()
-
-	d.LastCompletionTimestamp = proto.Int64(c.LastCompletionTimestamp.Unix())
 }
 
 // curationKey provides a representation of dto.CurationKey with associated

storage/metric/frontier.go

@@ -194,19 +194,3 @@ func (s *seriesFrontier) InSafeSeekRange(t time.Time) (safe bool) {
 func (s *seriesFrontier) After(t time.Time) bool {
 	return s.firstSupertime.After(t)
 }
-
-// optimalStartTime indicates what the best start time for a curation operation
-// should be given the curation remark.
-func (s *seriesFrontier) optimalStartTime(remark *curationRemark) (t time.Time) {
-	switch {
-	case remark == nil:
-		t = s.firstSupertime
-	case s.After(remark.LastCompletionTimestamp):
-		t = s.firstSupertime
-	case !s.InSafeSeekRange(remark.LastCompletionTimestamp):
-		t = s.lastSupertime
-	default:
-		t = remark.LastCompletionTimestamp
-	}
-	return
-}

storage/metric/index.go

@@ -14,7 +14,6 @@
 package metric
 
 import (
-	"io"
 	"sort"
 
 	"code.google.com/p/goprotobuf/proto"
@@ -31,7 +30,6 @@ import (
 type FingerprintMetricMapping map[clientmodel.Fingerprint]clientmodel.Metric
 
 type FingerprintMetricIndex interface {
-	io.Closer
 	raw.Pruner
 
 	IndexBatch(FingerprintMetricMapping) error
@@ -40,7 +38,7 @@ type FingerprintMetricIndex interface {
 	Size() (s uint64, present bool, err error)
 }
 
-type LeveldbFingerprintMetricIndex struct {
+type LevelDBFingerprintMetricIndex struct {
 	p *leveldb.LevelDBPersistence
 }
 
@@ -48,22 +46,20 @@ type LevelDBFingerprintMetricIndexOptions struct {
 	leveldb.LevelDBOptions
 }
 
-func (i *LeveldbFingerprintMetricIndex) Close() error {
+func (i *LevelDBFingerprintMetricIndex) Close() {
 	i.p.Close()
-
-	return nil
 }
 
-func (i *LeveldbFingerprintMetricIndex) State() *raw.DatabaseState {
+func (i *LevelDBFingerprintMetricIndex) State() *raw.DatabaseState {
 	return i.p.State()
 }
 
-func (i *LeveldbFingerprintMetricIndex) Size() (uint64, bool, error) {
+func (i *LevelDBFingerprintMetricIndex) Size() (uint64, bool, error) {
-	s, err := i.p.ApproximateSize()
+	s, err := i.p.Size()
 	return s, true, err
 }
 
-func (i *LeveldbFingerprintMetricIndex) IndexBatch(mapping FingerprintMetricMapping) error {
+func (i *LevelDBFingerprintMetricIndex) IndexBatch(mapping FingerprintMetricMapping) error {
 	b := leveldb.NewBatch()
 	defer b.Close()
 
@@ -79,7 +75,7 @@ func (i *LeveldbFingerprintMetricIndex) IndexBatch(mapping FingerprintMetricMapp
 	return i.p.Commit(b)
 }
 
-func (i *LeveldbFingerprintMetricIndex) Lookup(f *clientmodel.Fingerprint) (m clientmodel.Metric, ok bool, err error) {
+func (i *LevelDBFingerprintMetricIndex) Lookup(f *clientmodel.Fingerprint) (m clientmodel.Metric, ok bool, err error) {
 	k := new(dto.Fingerprint)
 	dumpFingerprint(k, f)
 	v := new(dto.Metric)
@@ -98,19 +94,19 @@ func (i *LeveldbFingerprintMetricIndex) Lookup(f *clientmodel.Fingerprint) (m cl
 	return m, true, nil
 }
 
-func (i *LeveldbFingerprintMetricIndex) Prune() (bool, error) {
+func (i *LevelDBFingerprintMetricIndex) Prune() (bool, error) {
 	i.p.Prune()
 
 	return false, nil
 }
 
-func NewLevelDBFingerprintMetricIndex(o *LevelDBFingerprintMetricIndexOptions) (FingerprintMetricIndex, error) {
+func NewLevelDBFingerprintMetricIndex(o *LevelDBFingerprintMetricIndexOptions) (*LevelDBFingerprintMetricIndex, error) {
 	s, err := leveldb.NewLevelDBPersistence(&o.LevelDBOptions)
 	if err != nil {
 		return nil, err
 	}
 
-	return &LeveldbFingerprintMetricIndex{
+	return &LevelDBFingerprintMetricIndex{
 		p: s,
 	}, nil
 }
@@ -118,7 +114,6 @@ func NewLevelDBFingerprintMetricIndex(o *LevelDBFingerprintMetricIndexOptions) (
 type LabelNameFingerprintMapping map[clientmodel.LabelName]clientmodel.Fingerprints
 
 type LabelNameFingerprintIndex interface {
-	io.Closer
 	raw.Pruner
 
 	IndexBatch(LabelNameFingerprintMapping) error
@@ -128,11 +123,11 @@ type LabelNameFingerprintIndex interface {
 	Size() (s uint64, present bool, err error)
 }
 
-type LeveldbLabelNameFingerprintIndex struct {
+type LevelDBLabelNameFingerprintIndex struct {
 	p *leveldb.LevelDBPersistence
 }
 
-func (i *LeveldbLabelNameFingerprintIndex) IndexBatch(b LabelNameFingerprintMapping) error {
+func (i *LevelDBLabelNameFingerprintIndex) IndexBatch(b LabelNameFingerprintMapping) error {
 	batch := leveldb.NewBatch()
 	defer batch.Close()
 
@@ -155,7 +150,7 @@ func (i *LeveldbLabelNameFingerprintIndex) IndexBatch(b LabelNameFingerprintMapp
 	return i.p.Commit(batch)
 }
 
-func (i *LeveldbLabelNameFingerprintIndex) Lookup(l clientmodel.LabelName) (fps clientmodel.Fingerprints, ok bool, err error) {
+func (i *LevelDBLabelNameFingerprintIndex) Lookup(l clientmodel.LabelName) (fps clientmodel.Fingerprints, ok bool, err error) {
 	k := new(dto.LabelName)
 	dumpLabelName(k, l)
 	v := new(dto.FingerprintCollection)
@@ -176,30 +171,28 @@ func (i *LeveldbLabelNameFingerprintIndex) Lookup(l clientmodel.LabelName) (fps
 	return fps, true, nil
 }
 
-func (i *LeveldbLabelNameFingerprintIndex) Has(l clientmodel.LabelName) (ok bool, err error) {
+func (i *LevelDBLabelNameFingerprintIndex) Has(l clientmodel.LabelName) (ok bool, err error) {
 	return i.p.Has(&dto.LabelName{
 		Name: proto.String(string(l)),
 	})
 }
 
-func (i *LeveldbLabelNameFingerprintIndex) Prune() (bool, error) {
+func (i *LevelDBLabelNameFingerprintIndex) Prune() (bool, error) {
 	i.p.Prune()
 
 	return false, nil
 }
 
-func (i *LeveldbLabelNameFingerprintIndex) Close() error {
+func (i *LevelDBLabelNameFingerprintIndex) Close() {
 	i.p.Close()
-
-	return nil
 }
 
-func (i *LeveldbLabelNameFingerprintIndex) Size() (uint64, bool, error) {
+func (i *LevelDBLabelNameFingerprintIndex) Size() (uint64, bool, error) {
-	s, err := i.p.ApproximateSize()
+	s, err := i.p.Size()
 	return s, true, err
 }
 
-func (i *LeveldbLabelNameFingerprintIndex) State() *raw.DatabaseState {
+func (i *LevelDBLabelNameFingerprintIndex) State() *raw.DatabaseState {
 	return i.p.State()
 }
 
@@ -207,13 +200,13 @@ type LevelDBLabelNameFingerprintIndexOptions struct {
 	leveldb.LevelDBOptions
 }
 
-func NewLevelLabelNameFingerprintIndex(o *LevelDBLabelNameFingerprintIndexOptions) (LabelNameFingerprintIndex, error) {
+func NewLevelLabelNameFingerprintIndex(o *LevelDBLabelNameFingerprintIndexOptions) (*LevelDBLabelNameFingerprintIndex, error) {
 	s, err := leveldb.NewLevelDBPersistence(&o.LevelDBOptions)
 	if err != nil {
 		return nil, err
 	}
 
-	return &LeveldbLabelNameFingerprintIndex{
+	return &LevelDBLabelNameFingerprintIndex{
 		p: s,
 	}, nil
 }
@@ -221,7 +214,6 @@ func NewLevelLabelNameFingerprintIndex(o *LevelDBLabelNameFingerprintIndexOption
 type LabelSetFingerprintMapping map[LabelPair]clientmodel.Fingerprints
 
 type LabelSetFingerprintIndex interface {
-	io.Closer
 	raw.ForEacher
 	raw.Pruner
 
@@ -232,7 +224,7 @@ type LabelSetFingerprintIndex interface {
 	Size() (s uint64, present bool, err error)
 }
 
-type LeveldbLabelSetFingerprintIndex struct {
+type LevelDBLabelSetFingerprintIndex struct {
 	p *leveldb.LevelDBPersistence
 }
 
@@ -240,7 +232,7 @@ type LevelDBLabelSetFingerprintIndexOptions struct {
 	leveldb.LevelDBOptions
 }
 
-func (i *LeveldbLabelSetFingerprintIndex) IndexBatch(m LabelSetFingerprintMapping) error {
+func (i *LevelDBLabelSetFingerprintIndex) IndexBatch(m LabelSetFingerprintMapping) error {
 	batch := leveldb.NewBatch()
 	defer batch.Close()
 
@@ -264,7 +256,7 @@ func (i *LeveldbLabelSetFingerprintIndex) IndexBatch(m LabelSetFingerprintMappin
 	return i.p.Commit(batch)
 }
 
-func (i *LeveldbLabelSetFingerprintIndex) Lookup(p *LabelPair) (m clientmodel.Fingerprints, ok bool, err error) {
+func (i *LevelDBLabelSetFingerprintIndex) Lookup(p *LabelPair) (m clientmodel.Fingerprints, ok bool, err error) {
 	k := &dto.LabelPair{
 		Name:  proto.String(string(p.Name)),
 		Value: proto.String(string(p.Value)),
@@ -289,7 +281,7 @@ func (i *LeveldbLabelSetFingerprintIndex) Lookup(p *LabelPair) (m clientmodel.Fi
 	return m, true, nil
 }
 
-func (i *LeveldbLabelSetFingerprintIndex) Has(p *LabelPair) (ok bool, err error) {
+func (i *LevelDBLabelSetFingerprintIndex) Has(p *LabelPair) (ok bool, err error) {
 	k := &dto.LabelPair{
 		Name:  proto.String(string(p.Name)),
 		Value: proto.String(string(p.Value)),
@@ -298,43 +290,40 @@ func (i *LeveldbLabelSetFingerprintIndex) Has(p *LabelPair) (ok bool, err error)
 	return i.p.Has(k)
 }
 
-func (i *LeveldbLabelSetFingerprintIndex) ForEach(d storage.RecordDecoder, f storage.RecordFilter, o storage.RecordOperator) (bool, error) {
+func (i *LevelDBLabelSetFingerprintIndex) ForEach(d storage.RecordDecoder, f storage.RecordFilter, o storage.RecordOperator) (bool, error) {
 	return i.p.ForEach(d, f, o)
 }
 
-func (i *LeveldbLabelSetFingerprintIndex) Prune() (bool, error) {
+func (i *LevelDBLabelSetFingerprintIndex) Prune() (bool, error) {
 	i.p.Prune()
 	return false, nil
 }
 
-func (i *LeveldbLabelSetFingerprintIndex) Close() error {
+func (i *LevelDBLabelSetFingerprintIndex) Close() {
 	i.p.Close()
-
-	return nil
 }
 
-func (i *LeveldbLabelSetFingerprintIndex) Size() (uint64, bool, error) {
+func (i *LevelDBLabelSetFingerprintIndex) Size() (uint64, bool, error) {
-	s, err := i.p.ApproximateSize()
+	s, err := i.p.Size()
 	return s, true, err
 }
 
-func (i *LeveldbLabelSetFingerprintIndex) State() *raw.DatabaseState {
+func (i *LevelDBLabelSetFingerprintIndex) State() *raw.DatabaseState {
 	return i.p.State()
 }
 
-func NewLevelDBLabelSetFingerprintIndex(o *LevelDBLabelSetFingerprintIndexOptions) (LabelSetFingerprintIndex, error) {
+func NewLevelDBLabelSetFingerprintIndex(o *LevelDBLabelSetFingerprintIndexOptions) (*LevelDBLabelSetFingerprintIndex, error) {
 	s, err := leveldb.NewLevelDBPersistence(&o.LevelDBOptions)
 	if err != nil {
 		return nil, err
 	}
 
-	return &LeveldbLabelSetFingerprintIndex{
+	return &LevelDBLabelSetFingerprintIndex{
 		p: s,
 	}, nil
 }
 
 type MetricMembershipIndex interface {
-	io.Closer
 	raw.Pruner
 
 	IndexBatch([]clientmodel.Metric) error
@@ -343,13 +332,13 @@ type MetricMembershipIndex interface {
 	Size() (s uint64, present bool, err error)
 }
 
-type LeveldbMetricMembershipIndex struct {
+type LevelDBMetricMembershipIndex struct {
 	p *leveldb.LevelDBPersistence
 }
 
 var existenceIdentity = new(dto.MembershipIndexValue)
 
-func (i *LeveldbMetricMembershipIndex) IndexBatch(ms []clientmodel.Metric) error {
+func (i *LevelDBMetricMembershipIndex) IndexBatch(ms []clientmodel.Metric) error {
 	batch := leveldb.NewBatch()
 	defer batch.Close()
 
@@ -362,29 +351,27 @@ func (i *LeveldbMetricMembershipIndex) IndexBatch(ms []clientmodel.Metric) error
 	return i.p.Commit(batch)
 }
 
-func (i *LeveldbMetricMembershipIndex) Has(m clientmodel.Metric) (ok bool, err error) {
+func (i *LevelDBMetricMembershipIndex) Has(m clientmodel.Metric) (ok bool, err error) {
 	k := new(dto.Metric)
 	dumpMetric(k, m)
 
 	return i.p.Has(k)
 }
 
-func (i *LeveldbMetricMembershipIndex) Close() error {
+func (i *LevelDBMetricMembershipIndex) Close() {
 	i.p.Close()
-
-	return nil
 }
 
-func (i *LeveldbMetricMembershipIndex) Size() (uint64, bool, error) {
+func (i *LevelDBMetricMembershipIndex) Size() (uint64, bool, error) {
-	s, err := i.p.ApproximateSize()
+	s, err := i.p.Size()
 	return s, true, err
 }
 
-func (i *LeveldbMetricMembershipIndex) State() *raw.DatabaseState {
+func (i *LevelDBMetricMembershipIndex) State() *raw.DatabaseState {
 	return i.p.State()
 }
 
-func (i *LeveldbMetricMembershipIndex) Prune() (bool, error) {
+func (i *LevelDBMetricMembershipIndex) Prune() (bool, error) {
 	i.p.Prune()
 
 	return false, nil
@@ -394,13 +381,13 @@ type LevelDBMetricMembershipIndexOptions struct {
 	leveldb.LevelDBOptions
 }
 
-func NewLevelDBMetricMembershipIndex(o *LevelDBMetricMembershipIndexOptions) (MetricMembershipIndex, error) {
+func NewLevelDBMetricMembershipIndex(o *LevelDBMetricMembershipIndexOptions) (*LevelDBMetricMembershipIndex, error) {
 	s, err := leveldb.NewLevelDBPersistence(&o.LevelDBOptions)
 	if err != nil {
 		return nil, err
 	}
 
-	return &LeveldbMetricMembershipIndex{
+	return &LevelDBMetricMembershipIndex{
 		p: s,
 	}, nil
 }

storage/metric/leveldb.go

@@ -36,7 +36,7 @@ import (
 const sortConcurrency = 2
 
 type LevelDBMetricPersistence struct {
-	CurationRemarks         *leveldb.LevelDBPersistence
+	CurationRemarks         CurationRemarker
 	fingerprintToMetrics    FingerprintMetricIndex
 	labelNameToFingerprints LabelNameFingerprintIndex
 	labelSetToFingerprints  LabelSetFingerprintIndex
@@ -202,13 +202,14 @@ func NewLevelDBMetricPersistence(baseDirectory string) (*LevelDBMetricPersistenc
 			"Sample Curation Remarks",
 			func() {
 				var err error
-				o := &leveldb.LevelDBOptions{
+				emission.CurationRemarks, err = NewLevelDBCurationRemarker(&LevelDBCurationRemarkerOptions{
+					LevelDBOptions: leveldb.LevelDBOptions{
 						Name:           "Sample Curation Remarks",
 						Purpose:        "Ledger of Progress for Various Curators",
 						Path:           baseDirectory + "/curation_remarks",
 						CacheSizeBytes: *curationRemarksCacheSize,
-				}
+					},
-				emission.CurationRemarks, err = leveldb.NewLevelDBPersistence(o)
+				})
 				workers.MayFail(err)
 			},
 		},
@@ -764,7 +765,7 @@ func (l *LevelDBMetricPersistence) GetAllValuesForLabel(labelName clientmodel.La
 	return
 }
 
-// CompactKeyspace compacts each database's keyspace serially.
+// Prune compacts each database's keyspace serially.
 //
 // Beware that it would probably be imprudent to run this on a live user-facing
 // server due to latency implications.
@@ -778,10 +779,10 @@ func (l *LevelDBMetricPersistence) Prune() {
 	l.MetricSamples.Prune()
 }
 
-func (l *LevelDBMetricPersistence) ApproximateSizes() (total uint64, err error) {
+func (l *LevelDBMetricPersistence) Sizes() (total uint64, err error) {
 	size := uint64(0)
 
-	if size, err = l.CurationRemarks.ApproximateSize(); err != nil {
+	if size, _, err = l.CurationRemarks.Size(); err != nil {
 		return 0, err
 	}
 	total += size
@@ -811,7 +812,7 @@ func (l *LevelDBMetricPersistence) ApproximateSizes() (total uint64, err error)
 	}
 	total += size
 
-	if size, err = l.MetricSamples.ApproximateSize(); err != nil {
+	if size, err = l.MetricSamples.Size(); err != nil {
 		return 0, err
 	}
 	total += size

storage/metric/processor_test.go

@@ -72,13 +72,10 @@ func (c curationState) Get() (key, value proto.Message) {
 
 	k := &dto.CurationKey{}
 	keyRaw.dump(k)
-	key = k
 
-	valueRaw := curationRemark{
+	v := &dto.CurationValue{
-		LastCompletionTimestamp: c.lastCurated,
+		LastCompletionTimestamp: proto.Int64(c.lastCurated.Unix()),
 	}
-	v := &dto.CurationValue{}
-	valueRaw.dump(v)
 
 	return k, v
 }
@@ -848,8 +845,10 @@ func TestCuratorCompactionProcessor(t *testing.T) {
 		sampleDirectory := fixture.NewPreparer(t).Prepare("sample", fixture.NewCassetteFactory(scenario.in.sampleGroups))
 		defer sampleDirectory.Close()
 
-		curatorStates, err := leveldb.NewLevelDBPersistence(&leveldb.LevelDBOptions{
+		curatorStates, err := NewLevelDBCurationRemarker(&LevelDBCurationRemarkerOptions{
+			LevelDBOptions: leveldb.LevelDBOptions{
 				Path: curatorDirectory.Path(),
+			},
 		})
 		if err != nil {
 			t.Fatal(err)
@@ -888,7 +887,7 @@ func TestCuratorCompactionProcessor(t *testing.T) {
 			t.Fatal(err)
 		}
 
-		iterator := curatorStates.NewIterator(true)
+		iterator := curatorStates.p.NewIterator(true)
 		defer iterator.Close()
 
 		for j, expected := range scenario.out.curationStates {
@@ -904,38 +903,35 @@ func TestCuratorCompactionProcessor(t *testing.T) {
 			}
 
 			curationKeyDto := &dto.CurationKey{}
-			curationValueDto := &dto.CurationValue{}
 
 			err = proto.Unmarshal(iterator.Key(), curationKeyDto)
 			if err != nil {
 				t.Fatalf("%d.%d. could not unmarshal: %s", i, j, err)
 			}
-			err = proto.Unmarshal(iterator.Value(), curationValueDto)
+			actualKey := new(curationKey)
-			if err != nil {
-				t.Fatalf("%d.%d. could not unmarshal: %s", i, j, err)
-			}
-			actualKey := &curationKey{}
 			actualKey.load(curationKeyDto)
-			actualCurationRemark := &curationRemark{}
+
-			actualCurationRemark.load(curationValueDto)
+			actualValue, present, err := curatorStates.Get(actualKey)
-			signature := expected.processor.Signature()
+			if !present {
+				t.Fatalf("%d.%d. could not get key-value pair %s", i, j, actualKey)
+			}
+			if err != nil {
+				t.Fatalf("%d.%d. could not get key-value pair %s", i, j, err)
+			}
 
 			expectedFingerprint := &clientmodel.Fingerprint{}
 			expectedFingerprint.LoadFromString(expected.fingerprint)
 			expectedKey := &curationKey{
 				Fingerprint:              expectedFingerprint,
 				IgnoreYoungerThan:        expected.ignoreYoungerThan,
-				ProcessorMessageRaw:      signature,
+				ProcessorMessageRaw:      expected.processor.Signature(),
 				ProcessorMessageTypeName: expected.processor.Name(),
 			}
 			if !actualKey.Equal(expectedKey) {
 				t.Fatalf("%d.%d. expected %s, got %s", i, j, expectedKey, actualKey)
 			}
-			expectedCurationRemark := curationRemark{
+			if !actualValue.Equal(expected.lastCurated) {
-				LastCompletionTimestamp: expected.lastCurated,
+				t.Fatalf("%d.%d. expected %s, got %s", i, j, expected.lastCurated, actualValue)
-			}
-			if !actualCurationRemark.Equal(expectedCurationRemark) {
-				t.Fatalf("%d.%d. expected %s, got %s", i, j, expectedCurationRemark, actualCurationRemark)
 			}
 		}
 
@@ -1374,8 +1370,11 @@ func TestCuratorDeletionProcessor(t *testing.T) {
 		sampleDirectory := fixture.NewPreparer(t).Prepare("sample", fixture.NewCassetteFactory(scenario.in.sampleGroups))
 		defer sampleDirectory.Close()
 
-		curatorStates, err := leveldb.NewLevelDBPersistence(&leveldb.LevelDBOptions{
+		curatorStates, err := NewLevelDBCurationRemarker(&LevelDBCurationRemarkerOptions{
-			Path: curatorDirectory.Path()})
+			LevelDBOptions: leveldb.LevelDBOptions{
+				Path: curatorDirectory.Path(),
+			},
+		})
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -1412,7 +1411,7 @@ func TestCuratorDeletionProcessor(t *testing.T) {
 			t.Fatal(err)
 		}
 
-		iterator := curatorStates.NewIterator(true)
+		iterator := curatorStates.p.NewIterator(true)
 		defer iterator.Close()
 
 		for j, expected := range scenario.out.curationStates {
@@ -1427,24 +1426,25 @@ func TestCuratorDeletionProcessor(t *testing.T) {
 				}
 			}
 
-			curationKeyDto := &dto.CurationKey{}
+			curationKeyDto := new(dto.CurationKey)
-			curationValueDto := &dto.CurationValue{}
 
 			err = proto.Unmarshal(iterator.Key(), curationKeyDto)
 			if err != nil {
 				t.Fatalf("%d.%d. could not unmarshal: %s", i, j, err)
 			}
-			err = proto.Unmarshal(iterator.Value(), curationValueDto)
-			if err != nil {
-				t.Fatalf("%d.%d. could not unmarshal: %s", i, j, err)
-			}
 
-			actualKey := &curationKey{}
+			actualKey := new(curationKey)
 			actualKey.load(curationKeyDto)
-			actualCurationRemark := &curationRemark{}
-			actualCurationRemark.load(curationValueDto)
 			signature := expected.processor.Signature()
 
+			actualValue, present, err := curatorStates.Get(actualKey)
+			if !present {
+				t.Fatalf("%d.%d. could not get key-value pair %s", i, j, actualKey)
+			}
+			if err != nil {
+				t.Fatalf("%d.%d. could not get key-value pair %s", i, j, err)
+			}
+
 			expectedFingerprint := &clientmodel.Fingerprint{}
 			expectedFingerprint.LoadFromString(expected.fingerprint)
 			expectedKey := &curationKey{
@@ -1456,11 +1456,8 @@ func TestCuratorDeletionProcessor(t *testing.T) {
 			if !actualKey.Equal(expectedKey) {
 				t.Fatalf("%d.%d. expected %s, got %s", i, j, expectedKey, actualKey)
 			}
-			expectedCurationRemark := curationRemark{
+			if !actualValue.Equal(expected.lastCurated) {
-				LastCompletionTimestamp: expected.lastCurated,
+				t.Fatalf("%d.%d. expected %s, got %s", i, j, expected.lastCurated, actualValue)
-			}
-			if !actualCurationRemark.Equal(expectedCurationRemark) {
-				t.Fatalf("%d.%d. expected %s, got %s", i, j, expectedCurationRemark, actualCurationRemark)
 			}
 		}
 

storage/metric/watermark.go

@@ -15,7 +15,6 @@ package metric
 
 import (
 	"container/list"
-	"io"
 	"sync"
 	"time"
 
@@ -171,7 +170,6 @@ func (lru *WatermarkCache) checkCapacity() {
 type FingerprintHighWatermarkMapping map[clientmodel.Fingerprint]time.Time
 
 type HighWatermarker interface {
-	io.Closer
 	raw.ForEacher
 	raw.Pruner
 
@@ -181,11 +179,11 @@ type HighWatermarker interface {
 	Size() (uint64, bool, error)
 }
 
-type LeveldbHighWatermarker struct {
+type LevelDBHighWatermarker struct {
 	p *leveldb.LevelDBPersistence
 }
 
-func (w *LeveldbHighWatermarker) Get(f *clientmodel.Fingerprint) (t time.Time, ok bool, err error) {
+func (w *LevelDBHighWatermarker) Get(f *clientmodel.Fingerprint) (t time.Time, ok bool, err error) {
 	k := new(dto.Fingerprint)
 	dumpFingerprint(k, f)
 	v := new(dto.MetricHighWatermark)
@@ -200,7 +198,7 @@ func (w *LeveldbHighWatermarker) Get(f *clientmodel.Fingerprint) (t time.Time, o
 	return t, true, nil
 }
 
-func (w *LeveldbHighWatermarker) UpdateBatch(m FingerprintHighWatermarkMapping) error {
+func (w *LevelDBHighWatermarker) UpdateBatch(m FingerprintHighWatermarkMapping) error {
 	batch := leveldb.NewBatch()
 	defer batch.Close()
 
@@ -229,28 +227,26 @@ func (w *LeveldbHighWatermarker) UpdateBatch(m FingerprintHighWatermarkMapping)
 	return w.p.Commit(batch)
 }
 
-func (i *LeveldbHighWatermarker) ForEach(d storage.RecordDecoder, f storage.RecordFilter, o storage.RecordOperator) (bool, error) {
+func (w *LevelDBHighWatermarker) ForEach(d storage.RecordDecoder, f storage.RecordFilter, o storage.RecordOperator) (bool, error) {
-	return i.p.ForEach(d, f, o)
+	return w.p.ForEach(d, f, o)
 }
 
-func (i *LeveldbHighWatermarker) Prune() (bool, error) {
+func (w *LevelDBHighWatermarker) Prune() (bool, error) {
-	i.p.Prune()
+	w.p.Prune()
 
 	return false, nil
 }
 
-func (i *LeveldbHighWatermarker) Close() error {
+func (w *LevelDBHighWatermarker) Close() {
-	i.p.Close()
+	w.p.Close()
-
-	return nil
 }
 
-func (i *LeveldbHighWatermarker) State() *raw.DatabaseState {
+func (w *LevelDBHighWatermarker) State() *raw.DatabaseState {
-	return i.p.State()
+	return w.p.State()
 }
 
-func (i *LeveldbHighWatermarker) Size() (uint64, bool, error) {
+func (w *LevelDBHighWatermarker) Size() (uint64, bool, error) {
-	s, err := i.p.ApproximateSize()
+	s, err := w.p.Size()
 	return s, true, err
 }
 
@@ -258,13 +254,82 @@ type LevelDBHighWatermarkerOptions struct {
 	leveldb.LevelDBOptions
 }
 
-func NewLevelDBHighWatermarker(o *LevelDBHighWatermarkerOptions) (HighWatermarker, error) {
+func NewLevelDBHighWatermarker(o *LevelDBHighWatermarkerOptions) (*LevelDBHighWatermarker, error) {
 	s, err := leveldb.NewLevelDBPersistence(&o.LevelDBOptions)
 	if err != nil {
 		return nil, err
 	}
 
-	return &LeveldbHighWatermarker{
+	return &LevelDBHighWatermarker{
+		p: s,
+	}, nil
+}
+
+type CurationRemarker interface {
+	raw.Pruner
+
+	Update(*curationKey, time.Time) error
+	Get(*curationKey) (t time.Time, ok bool, err error)
+	State() *raw.DatabaseState
+	Size() (uint64, bool, error)
+}
+
+type LevelDBCurationRemarker struct {
+	p *leveldb.LevelDBPersistence
+}
+
+type LevelDBCurationRemarkerOptions struct {
+	leveldb.LevelDBOptions
+}
+
+func (w *LevelDBCurationRemarker) State() *raw.DatabaseState {
+	return w.p.State()
+}
+
+func (w *LevelDBCurationRemarker) Size() (uint64, bool, error) {
+	s, err := w.p.Size()
+	return s, true, err
+}
+
+func (w *LevelDBCurationRemarker) Close() {
+	w.p.Close()
+}
+
+func (w *LevelDBCurationRemarker) Prune() (bool, error) {
+	w.p.Prune()
+
+	return false, nil
+}
+
+func (w *LevelDBCurationRemarker) Get(c *curationKey) (t time.Time, ok bool, err error) {
+	k := new(dto.CurationKey)
+	c.dump(k)
+	v := new(dto.CurationValue)
+
+	ok, err = w.p.Get(k, v)
+	if err != nil || !ok {
+		return t, ok, err
+	}
+
+	return time.Unix(v.GetLastCompletionTimestamp(), 0).UTC(), true, nil
+}
+
+func (w *LevelDBCurationRemarker) Update(pair *curationKey, t time.Time) error {
+	k := new(dto.CurationKey)
+	pair.dump(k)
+
+	return w.p.Put(k, &dto.CurationValue{
+		LastCompletionTimestamp: proto.Int64(t.Unix()),
+	})
+}
+
+func NewLevelDBCurationRemarker(o *LevelDBCurationRemarkerOptions) (*LevelDBCurationRemarker, error) {
+	s, err := leveldb.NewLevelDBPersistence(&o.LevelDBOptions)
+	if err != nil {
+		return nil, err
+	}
+
+	return &LevelDBCurationRemarker{
 		p: s,
 	}, nil
 }

storage/raw/index/leveldb/leveldb.go

@@ -71,8 +71,8 @@ func (l *LevelDBMembershipIndex) Prune() {
 	l.persistence.Prune()
 }
 
-func (l *LevelDBMembershipIndex) ApproximateSize() (uint64, error) {
+func (l *LevelDBMembershipIndex) Size() (uint64, error) {
-	return l.persistence.ApproximateSize()
+	return l.persistence.Size()
 }
 
 func (l *LevelDBMembershipIndex) State() *raw.DatabaseState {

storage/raw/leveldb/leveldb.go

@@ -332,7 +332,7 @@ func (l *LevelDBPersistence) Prune() {
 	l.storage.CompactRange(keyspace)
 }
 
-func (l *LevelDBPersistence) ApproximateSize() (uint64, error) {
+func (l *LevelDBPersistence) Size() (uint64, error) {
 	iterator := l.NewIterator(false)
 	defer iterator.Close()
 

storage/raw/leveldb/state.go

@@ -31,7 +31,7 @@ func (l *LevelDBPersistence) State() *raw.DatabaseState {
 		Supplemental: map[string]string{},
 	}
 
-	if size, err := l.ApproximateSize(); err != nil {
+	if size, err := l.Size(); err != nil {
 		databaseState.Supplemental["Errors"] = err.Error()
 	} else {
 		databaseState.Size = utility.ByteSize(size)

tools/pruner/main.go

@@ -42,10 +42,10 @@ func main() {
 
 	start := time.Now()
 	log.Printf("Starting compaction...")
-	size, _ := persistences.ApproximateSizes()
+	size, _ := persistences.Sizes()
 	log.Printf("Original Size: %d", size)
 	persistences.Prune()
 	log.Printf("Finished in %s", time.Since(start))
-	size, _ = persistences.ApproximateSizes()
+	size, _ = persistences.Sizes()
 	log.Printf("New Size: %d", size)
 }