diff --git a/storage/local/chunk.go b/storage/local/chunk.go
index 112198c0de..eb4751aa57 100644
--- a/storage/local/chunk.go
+++ b/storage/local/chunk.go
@@ -25,6 +25,7 @@ import (
 	"github.com/prometheus/prometheus/storage/metric"
 )
 
+// The DefaultChunkEncoding can be changed via a flag.
 var DefaultChunkEncoding = doubleDelta
 
 type chunkEncoding byte
diff --git a/storage/local/crashrecovery.go b/storage/local/crashrecovery.go
index cbb0061bf4..4cccdbfbc2 100644
--- a/storage/local/crashrecovery.go
+++ b/storage/local/crashrecovery.go
@@ -254,7 +254,7 @@ func (p *persistence) sanitizeSeries(
 			// disk. Treat this series as a freshly unarchived one
 			// by loading the chunkDescs and setting all parameters
 			// based on the loaded chunkDescs.
-			cds, err := p.loadChunkDescs(fp, clientmodel.Latest)
+			cds, err := p.loadChunkDescs(fp, 0)
 			if err != nil {
 				log.Errorf(
 					"Failed to load chunk descriptors for metric %v, fingerprint %v: %s",
@@ -286,8 +286,7 @@ func (p *persistence) sanitizeSeries(
 		// First, throw away the chunkDescs without chunks.
 		s.chunkDescs = s.chunkDescs[s.persistWatermark:]
 		numMemChunkDescs.Sub(float64(s.persistWatermark))
-		// Load all the chunk descs.
-		cds, err := p.loadChunkDescs(fp, clientmodel.Latest)
+		cds, err := p.loadChunkDescs(fp, 0)
 		if err != nil {
 			log.Errorf(
 				"Failed to load chunk descriptors for metric %v, fingerprint %v: %s",
@@ -407,7 +406,7 @@ func (p *persistence) cleanUpArchiveIndexes(
 		if _, err := p.archivedFingerprintToMetrics.Delete(fp); err != nil {
 			return err
 		}
-		cds, err := p.loadChunkDescs(clientmodel.Fingerprint(fp), clientmodel.Latest)
+		cds, err := p.loadChunkDescs(clientmodel.Fingerprint(fp), 0)
 		if err != nil {
 			return err
 		}
diff --git a/storage/local/index/index.go b/storage/local/index/index.go
index dd31211fcf..5749cba9a8 100644
--- a/storage/local/index/index.go
+++ b/storage/local/index/index.go
@@ -33,6 +33,7 @@ const (
 	labelPairToFingerprintsDir = "labelpair_to_fingerprints"
 )
 
+// LevelDB cache sizes, changeable via flags.
 var (
 	FingerprintMetricCacheSize     = 10 * 1024 * 1024
 	FingerprintTimeRangeCacheSize  = 5 * 1024 * 1024
diff --git a/storage/local/persistence.go b/storage/local/persistence.go
index a629e23f43..d1a6955b1f 100644
--- a/storage/local/persistence.go
+++ b/storage/local/persistence.go
@@ -444,10 +444,11 @@ func (p *persistence) loadChunks(fp clientmodel.Fingerprint, indexes []int, inde
 	return chunks, nil
 }
 
-// loadChunkDescs loads chunkDescs for a series up until a given time.  It is
-// the caller's responsibility to not persist or drop anything for the same
+// loadChunkDescs loads the chunkDescs for a series from disk. offsetFromEnd is
+// the number of chunkDescs to skip from the end of the series file. It is the
+// caller's responsibility to not persist or drop anything for the same
 // fingerprint concurrently.
-func (p *persistence) loadChunkDescs(fp clientmodel.Fingerprint, beforeTime clientmodel.Timestamp) ([]*chunkDesc, error) {
+func (p *persistence) loadChunkDescs(fp clientmodel.Fingerprint, offsetFromEnd int) ([]*chunkDesc, error) {
 	f, err := p.openChunkFileForReading(fp)
 	if os.IsNotExist(err) {
 		return nil, nil
@@ -469,8 +470,8 @@ func (p *persistence) loadChunkDescs(fp clientmodel.Fingerprint, beforeTime clie
 		)
 	}
 
-	numChunks := int(fi.Size()) / chunkLenWithHeader
-	cds := make([]*chunkDesc, 0, numChunks)
+	numChunks := int(fi.Size())/chunkLenWithHeader - offsetFromEnd
+	cds := make([]*chunkDesc, numChunks)
 	chunkTimesBuf := make([]byte, 16)
 	for i := 0; i < numChunks; i++ {
 		_, err := f.Seek(offsetForChunkIndex(i)+chunkHeaderFirstTimeOffset, os.SEEK_SET)
@@ -482,15 +483,10 @@ func (p *persistence) loadChunkDescs(fp clientmodel.Fingerprint, beforeTime clie
 		if err != nil {
 			return nil, err
 		}
-		cd := &chunkDesc{
+		cds[i] = &chunkDesc{
 			chunkFirstTime: clientmodel.Timestamp(binary.LittleEndian.Uint64(chunkTimesBuf)),
 			chunkLastTime:  clientmodel.Timestamp(binary.LittleEndian.Uint64(chunkTimesBuf[8:])),
 		}
-		if !cd.chunkLastTime.Before(beforeTime) {
-			// From here on, we have chunkDescs in memory already.
-			break
-		}
-		cds = append(cds, cd)
 	}
 	chunkDescOps.WithLabelValues(load).Add(float64(len(cds)))
 	numMemChunkDescs.Add(float64(len(cds)))
diff --git a/storage/local/persistence_test.go b/storage/local/persistence_test.go
index 34bb672b39..0dcd7997ed 100644
--- a/storage/local/persistence_test.go
+++ b/storage/local/persistence_test.go
@@ -122,7 +122,7 @@ func testPersistLoadDropChunks(t *testing.T, encoding chunkEncoding) {
 			}
 		}
 		// Load all chunk descs.
-		actualChunkDescs, err := p.loadChunkDescs(fp, 10)
+		actualChunkDescs, err := p.loadChunkDescs(fp, 0)
 		if len(actualChunkDescs) != 10 {
 			t.Errorf("Got %d chunkDescs, want %d.", len(actualChunkDescs), 10)
 		}
@@ -974,7 +974,7 @@ func BenchmarkLoadChunkDescs(b *testing.B) {
 	for i := 0; i < b.N; i++ {
 		for _, s := range fpStrings {
 			fp.LoadFromString(s)
-			cds, err := p.loadChunkDescs(fp, clientmodel.Latest)
+			cds, err := p.loadChunkDescs(fp, 0)
 			if err != nil {
 				b.Error(err)
 			}
diff --git a/storage/local/series.go b/storage/local/series.go
index 07388a2e5f..87a193eef2 100644
--- a/storage/local/series.go
+++ b/storage/local/series.go
@@ -384,7 +384,7 @@ func (s *memorySeries) preloadChunksForRange(
 		firstChunkDescTime = s.chunkDescs[0].firstTime()
 	}
 	if s.chunkDescsOffset != 0 && from.Before(firstChunkDescTime) {
-		cds, err := mss.loadChunkDescs(fp, firstChunkDescTime)
+		cds, err := mss.loadChunkDescs(fp, s.persistWatermark)
 		if err != nil {
 			return nil, err
 		}
diff --git a/storage/local/storage.go b/storage/local/storage.go
index 7e0ef06c31..fa2461275a 100644
--- a/storage/local/storage.go
+++ b/storage/local/storage.go
@@ -589,7 +589,7 @@ func (s *memorySeriesStorage) getOrCreateSeries(fp clientmodel.Fingerprint, m cl
 			// end up with a series without any chunkDescs for a
 			// while (which is confusing as it makes the series
 			// appear as archived or purged).
-			cds, err = s.loadChunkDescs(fp, clientmodel.Latest)
+			cds, err = s.loadChunkDescs(fp, 0)
 			if err != nil {
 				log.Errorf("Error loading chunk descs for fingerprint %v (metric %v): %v", fp, m, err)
 			}
@@ -1107,8 +1107,8 @@ func (s *memorySeriesStorage) loadChunks(fp clientmodel.Fingerprint, indexes []i
 }
 
 // See persistence.loadChunkDescs for detailed explanation.
-func (s *memorySeriesStorage) loadChunkDescs(fp clientmodel.Fingerprint, beforeTime clientmodel.Timestamp) ([]*chunkDesc, error) {
-	return s.persistence.loadChunkDescs(fp, beforeTime)
+func (s *memorySeriesStorage) loadChunkDescs(fp clientmodel.Fingerprint, offsetFromEnd int) ([]*chunkDesc, error) {
+	return s.persistence.loadChunkDescs(fp, offsetFromEnd)
 }
 
 // getNumChunksToPersist returns numChunksToPersist in a goroutine-safe way.