Merge pull request #314 from grafana/jvp/fix-ooo-head-postingsformatchers-and-labelvalues

Fix OOO Head LabelValues and PostingsForMatchers

tsdb/db_test.go

@@ -4196,7 +4196,7 @@ func TestOOOAppendAndQuery(t *testing.T) {
 	s2 := labels.FromStrings("foo", "bar2")
 
 	minutes := func(m int64) int64 { return m * time.Minute.Milliseconds() }
-	expSamples := make(map[string][]tsdbutil.Sample)
+	appendedSamples := make(map[string][]tsdbutil.Sample)
 	totalSamples := 0
 	addSample := func(lbls labels.Labels, fromMins, toMins int64, faceError bool) {
 		app := db.Appender(context.Background())
@@ -4209,7 +4209,7 @@ func TestOOOAppendAndQuery(t *testing.T) {
 				require.Error(t, err)
 			} else {
 				require.NoError(t, err)
-				expSamples[key] = append(expSamples[key], sample{t: min, v: val})
+				appendedSamples[key] = append(appendedSamples[key], sample{t: min, v: val})
 				totalSamples++
 			}
 		}
@@ -4220,17 +4220,30 @@ func TestOOOAppendAndQuery(t *testing.T) {
 		}
 	}
 
-	testQuery := func() {
+	testQuery := func(from, to int64) {
-		querier, err := db.Querier(context.TODO(), math.MinInt64, math.MaxInt64)
+		querier, err := db.Querier(context.TODO(), from, to)
 		require.NoError(t, err)
 
 		seriesSet := query(t, querier, labels.MustNewMatcher(labels.MatchRegexp, "foo", "bar."))
 
-		for k, v := range expSamples {
+		for k, v := range appendedSamples {
 			sort.Slice(v, func(i, j int) bool {
 				return v[i].T() < v[j].T()
 			})
-			expSamples[k] = v
+			appendedSamples[k] = v
+		}
+
+		expSamples := make(map[string][]tsdbutil.Sample)
+		for k, samples := range appendedSamples {
+			for _, s := range samples {
+				if s.T() < from {
+					continue
+				}
+				if s.T() > to {
+					continue
+				}
+				expSamples[k] = append(expSamples[k], s)
+			}
 		}
 		require.Equal(t, expSamples, seriesSet)
 		require.Equal(t, float64(totalSamples-2), prom_testutil.ToFloat64(db.head.metrics.outOfOrderSamplesAppended), "number of ooo appended samples mismatch")
@@ -4245,40 +4258,43 @@ func TestOOOAppendAndQuery(t *testing.T) {
 	addSample(s1, 300, 300, false)
 	addSample(s2, 290, 290, false)
 	require.Equal(t, float64(2), prom_testutil.ToFloat64(db.head.metrics.chunksCreated))
-	testQuery()
+	testQuery(math.MinInt64, math.MaxInt64)
 
 	// Some ooo samples.
 	addSample(s1, 250, 260, false)
 	addSample(s2, 255, 265, false)
 	verifyOOOMinMaxTimes(250, 265)
-	testQuery()
+	testQuery(math.MinInt64, math.MaxInt64)
+	testQuery(minutes(250), minutes(265)) // Test querying ono data time range
+	testQuery(minutes(290), minutes(300)) // Test querying in-order data time range
+	testQuery(minutes(250), minutes(300)) // Test querying the entire range
 
 	// Out of time window.
 	addSample(s1, 59, 59, true)
 	addSample(s2, 49, 49, true)
 	verifyOOOMinMaxTimes(250, 265)
-	testQuery()
+	testQuery(math.MinInt64, math.MaxInt64)
 
 	// At the edge of time window, also it would be "out of bound" without the ooo support.
 	addSample(s1, 60, 65, false)
 	verifyOOOMinMaxTimes(60, 265)
-	testQuery()
+	testQuery(math.MinInt64, math.MaxInt64)
 
 	// This sample is not within the time window w.r.t. the head's maxt, but it is within the window
 	// w.r.t. the series' maxt. But we consider only head's maxt.
 	addSample(s2, 59, 59, true)
 	verifyOOOMinMaxTimes(60, 265)
-	testQuery()
+	testQuery(math.MinInt64, math.MaxInt64)
 
 	// Now the sample is within time window w.r.t. the head's maxt.
 	addSample(s2, 60, 65, false)
 	verifyOOOMinMaxTimes(60, 265)
-	testQuery()
+	testQuery(math.MinInt64, math.MaxInt64)
 
 	// Out of time window again.
 	addSample(s1, 59, 59, true)
 	addSample(s2, 49, 49, true)
-	testQuery()
+	testQuery(math.MinInt64, math.MaxInt64)
 
 	// Generating some m-map chunks. The m-map chunks here are in such a way
 	// that when sorted w.r.t. mint, the last chunk's maxt is not the overall maxt
@@ -4287,7 +4303,7 @@ func TestOOOAppendAndQuery(t *testing.T) {
 	addSample(s1, 180, 249, false)
 	require.Equal(t, float64(6), prom_testutil.ToFloat64(db.head.metrics.chunksCreated))
 	verifyOOOMinMaxTimes(60, 265)
-	testQuery()
+	testQuery(math.MinInt64, math.MaxInt64)
 }
 
 func TestOOODisabled(t *testing.T) {

tsdb/head_test.go

@@ -49,7 +49,7 @@ import (
 	"github.com/prometheus/prometheus/tsdb/wal"
 )
 
-func newTestHead(t testing.TB, chunkRange int64, compressWAL bool) (*Head, *wal.WAL) {
+func newTestHead(t testing.TB, chunkRange int64, compressWAL, oooEnabled bool) (*Head, *wal.WAL) {
 	dir := t.TempDir()
 	wlog, err := wal.NewSize(nil, nil, filepath.Join(dir, "wal"), 32768, compressWAL)
 	require.NoError(t, err)
@@ -59,6 +59,9 @@ func newTestHead(t testing.TB, chunkRange int64, compressWAL bool) (*Head, *wal.
 	opts.ChunkDirRoot = dir
 	opts.EnableExemplarStorage = true
 	opts.MaxExemplars.Store(config.DefaultExemplarsConfig.MaxExemplars)
+	if oooEnabled {
+		opts.OutOfOrderTimeWindow.Store(10 * time.Minute.Milliseconds())
+	}
 
 	h, err := NewHead(nil, nil, wlog, nil, opts, nil)
 	require.NoError(t, err)
@@ -72,7 +75,7 @@ func newTestHead(t testing.TB, chunkRange int64, compressWAL bool) (*Head, *wal.
 
 func BenchmarkCreateSeries(b *testing.B) {
 	series := genSeries(b.N, 10, 0, 0)
-	h, _ := newTestHead(b, 10000, false)
+	h, _ := newTestHead(b, 10000, false, false)
 	defer func() {
 		require.NoError(b, h.Close())
 	}()
@@ -270,7 +273,7 @@ func BenchmarkLoadWAL(b *testing.B) {
 // While appending the samples to the head it concurrently queries them from multiple go routines and verifies that the
 // returned results are correct.
 func TestHead_HighConcurrencyReadAndWrite(t *testing.T) {
-	head, _ := newTestHead(t, DefaultBlockDuration, false)
+	head, _ := newTestHead(t, DefaultBlockDuration, false, false)
 	defer func() {
 		require.NoError(t, head.Close())
 	}()
@@ -486,7 +489,7 @@ func TestHead_ReadWAL(t *testing.T) {
 				},
 			}
 
-			head, w := newTestHead(t, 1000, compress)
+			head, w := newTestHead(t, 1000, compress, false)
 			defer func() {
 				require.NoError(t, head.Close())
 			}()
@@ -530,7 +533,7 @@ func TestHead_ReadWAL(t *testing.T) {
 }
 
 func TestHead_WALMultiRef(t *testing.T) {
-	head, w := newTestHead(t, 1000, false)
+	head, w := newTestHead(t, 1000, false, false)
 
 	require.NoError(t, head.Init(0))
 
@@ -590,7 +593,7 @@ func TestHead_WALMultiRef(t *testing.T) {
 }
 
 func TestHead_ActiveAppenders(t *testing.T) {
-	head, _ := newTestHead(t, 1000, false)
+	head, _ := newTestHead(t, 1000, false, false)
 	defer head.Close()
 
 	require.NoError(t, head.Init(0))
@@ -623,14 +626,14 @@ func TestHead_ActiveAppenders(t *testing.T) {
 }
 
 func TestHead_UnknownWALRecord(t *testing.T) {
-	head, w := newTestHead(t, 1000, false)
+	head, w := newTestHead(t, 1000, false, false)
 	w.Log([]byte{255, 42})
 	require.NoError(t, head.Init(0))
 	require.NoError(t, head.Close())
 }
 
 func TestHead_Truncate(t *testing.T) {
-	h, _ := newTestHead(t, 1000, false)
+	h, _ := newTestHead(t, 1000, false, false)
 	defer func() {
 		require.NoError(t, h.Close())
 	}()
@@ -789,7 +792,7 @@ func TestHeadDeleteSeriesWithoutSamples(t *testing.T) {
 					{Ref: 50, T: 90, V: 1},
 				},
 			}
-			head, w := newTestHead(t, 1000, compress)
+			head, w := newTestHead(t, 1000, compress, false)
 			defer func() {
 				require.NoError(t, head.Close())
 			}()
@@ -856,7 +859,7 @@ func TestHeadDeleteSimple(t *testing.T) {
 	for _, compress := range []bool{false, true} {
 		t.Run(fmt.Sprintf("compress=%t", compress), func(t *testing.T) {
 			for _, c := range cases {
-				head, w := newTestHead(t, 1000, compress)
+				head, w := newTestHead(t, 1000, compress, false)
 				require.NoError(t, head.Init(0))
 
 				app := head.Appender(context.Background())
@@ -937,7 +940,7 @@ func TestHeadDeleteSimple(t *testing.T) {
 }
 
 func TestDeleteUntilCurMax(t *testing.T) {
-	hb, _ := newTestHead(t, 1000000, false)
+	hb, _ := newTestHead(t, 1000000, false, false)
 	defer func() {
 		require.NoError(t, hb.Close())
 	}()
@@ -990,7 +993,7 @@ func TestDeletedSamplesAndSeriesStillInWALAfterCheckpoint(t *testing.T) {
 	numSamples := 10000
 
 	// Enough samples to cause a checkpoint.
-	hb, w := newTestHead(t, int64(numSamples)*10, false)
+	hb, w := newTestHead(t, int64(numSamples)*10, false, false)
 
 	for i := 0; i < numSamples; i++ {
 		app := hb.Appender(context.Background())
@@ -1079,7 +1082,7 @@ func TestDelete_e2e(t *testing.T) {
 		seriesMap[labels.New(l...).String()] = []tsdbutil.Sample{}
 	}
 
-	hb, _ := newTestHead(t, 100000, false)
+	hb, _ := newTestHead(t, 100000, false, false)
 	defer func() {
 		require.NoError(t, hb.Close())
 	}()
@@ -1360,7 +1363,7 @@ func TestMemSeries_append_atVariableRate(t *testing.T) {
 
 func TestGCChunkAccess(t *testing.T) {
 	// Put a chunk, select it. GC it and then access it.
-	h, _ := newTestHead(t, 1000, false)
+	h, _ := newTestHead(t, 1000, false, false)
 	defer func() {
 		require.NoError(t, h.Close())
 	}()
@@ -1414,7 +1417,7 @@ func TestGCChunkAccess(t *testing.T) {
 
 func TestGCSeriesAccess(t *testing.T) {
 	// Put a series, select it. GC it and then access it.
-	h, _ := newTestHead(t, 1000, false)
+	h, _ := newTestHead(t, 1000, false, false)
 	defer func() {
 		require.NoError(t, h.Close())
 	}()
@@ -1469,7 +1472,7 @@ func TestGCSeriesAccess(t *testing.T) {
 }
 
 func TestUncommittedSamplesNotLostOnTruncate(t *testing.T) {
-	h, _ := newTestHead(t, 1000, false)
+	h, _ := newTestHead(t, 1000, false, false)
 	defer func() {
 		require.NoError(t, h.Close())
 	}()
@@ -1499,7 +1502,7 @@ func TestUncommittedSamplesNotLostOnTruncate(t *testing.T) {
 }
 
 func TestRemoveSeriesAfterRollbackAndTruncate(t *testing.T) {
-	h, _ := newTestHead(t, 1000, false)
+	h, _ := newTestHead(t, 1000, false, false)
 	defer func() {
 		require.NoError(t, h.Close())
 	}()
@@ -1532,7 +1535,7 @@ func TestRemoveSeriesAfterRollbackAndTruncate(t *testing.T) {
 func TestHead_LogRollback(t *testing.T) {
 	for _, compress := range []bool{false, true} {
 		t.Run(fmt.Sprintf("compress=%t", compress), func(t *testing.T) {
-			h, w := newTestHead(t, 1000, compress)
+			h, w := newTestHead(t, 1000, compress, false)
 			defer func() {
 				require.NoError(t, h.Close())
 			}()
@@ -1726,7 +1729,7 @@ func TestHeadReadWriterRepair(t *testing.T) {
 }
 
 func TestNewWalSegmentOnTruncate(t *testing.T) {
-	h, wlog := newTestHead(t, 1000, false)
+	h, wlog := newTestHead(t, 1000, false, false)
 	defer func() {
 		require.NoError(t, h.Close())
 	}()
@@ -1756,7 +1759,7 @@ func TestNewWalSegmentOnTruncate(t *testing.T) {
 }
 
 func TestAddDuplicateLabelName(t *testing.T) {
-	h, _ := newTestHead(t, 1000, false)
+	h, _ := newTestHead(t, 1000, false, false)
 	defer func() {
 		require.NoError(t, h.Close())
 	}()
@@ -1839,7 +1842,7 @@ func TestMemSeriesIsolation(t *testing.T) {
 	}
 
 	// Test isolation without restart of Head.
-	hb, _ := newTestHead(t, 1000, false)
+	hb, _ := newTestHead(t, 1000, false, false)
 	i := addSamples(hb)
 	testIsolation(hb, i)
 
@@ -1901,7 +1904,7 @@ func TestMemSeriesIsolation(t *testing.T) {
 	require.NoError(t, hb.Close())
 
 	// Test isolation with restart of Head. This is to verify the num samples of chunks after m-map chunk replay.
-	hb, w := newTestHead(t, 1000, false)
+	hb, w := newTestHead(t, 1000, false, false)
 	i = addSamples(hb)
 	require.NoError(t, hb.Close())
 
@@ -1954,7 +1957,7 @@ func TestIsolationRollback(t *testing.T) {
 	}
 
 	// Rollback after a failed append and test if the low watermark has progressed anyway.
-	hb, _ := newTestHead(t, 1000, false)
+	hb, _ := newTestHead(t, 1000, false, false)
 	defer func() {
 		require.NoError(t, hb.Close())
 	}()
@@ -1985,7 +1988,7 @@ func TestIsolationLowWatermarkMonotonous(t *testing.T) {
 		t.Skip("skipping test since tsdb isolation is disabled")
 	}
 
-	hb, _ := newTestHead(t, 1000, false)
+	hb, _ := newTestHead(t, 1000, false, false)
 	defer func() {
 		require.NoError(t, hb.Close())
 	}()
@@ -2022,7 +2025,7 @@ func TestIsolationAppendIDZeroIsNoop(t *testing.T) {
 		t.Skip("skipping test since tsdb isolation is disabled")
 	}
 
-	h, _ := newTestHead(t, 1000, false)
+	h, _ := newTestHead(t, 1000, false, false)
 	defer func() {
 		require.NoError(t, h.Close())
 	}()
@@ -2047,7 +2050,7 @@ func TestIsolationWithoutAdd(t *testing.T) {
 		t.Skip("skipping test since tsdb isolation is disabled")
 	}
 
-	hb, _ := newTestHead(t, 1000, false)
+	hb, _ := newTestHead(t, 1000, false, false)
 	defer func() {
 		require.NoError(t, hb.Close())
 	}()
@@ -2142,7 +2145,7 @@ func TestOutOfOrderSamplesMetric(t *testing.T) {
 }
 
 func testHeadSeriesChunkRace(t *testing.T) {
-	h, _ := newTestHead(t, 1000, false)
+	h, _ := newTestHead(t, 1000, false, false)
 	defer func() {
 		require.NoError(t, h.Close())
 	}()
@@ -2177,7 +2180,7 @@ func testHeadSeriesChunkRace(t *testing.T) {
 }
 
 func TestHeadLabelNamesValuesWithMinMaxRange(t *testing.T) {
-	head, _ := newTestHead(t, 1000, false)
+	head, _ := newTestHead(t, 1000, false, false)
 	defer func() {
 		require.NoError(t, head.Close())
 	}()
@@ -2237,7 +2240,7 @@ func TestHeadLabelNamesValuesWithMinMaxRange(t *testing.T) {
 }
 
 func TestHeadLabelValuesWithMatchers(t *testing.T) {
-	head, _ := newTestHead(t, 1000, false)
+	head, _ := newTestHead(t, 1000, false, false)
 	t.Cleanup(func() { require.NoError(t, head.Close()) })
 
 	app := head.Appender(context.Background())
@@ -2296,7 +2299,7 @@ func TestHeadLabelValuesWithMatchers(t *testing.T) {
 }
 
 func TestHeadLabelNamesWithMatchers(t *testing.T) {
-	head, _ := newTestHead(t, 1000, false)
+	head, _ := newTestHead(t, 1000, false, false)
 	defer func() {
 		require.NoError(t, head.Close())
 	}()
@@ -2364,7 +2367,7 @@ func TestHeadLabelNamesWithMatchers(t *testing.T) {
 }
 
 func TestHeadShardedPostings(t *testing.T) {
-	head, _ := newTestHead(t, 1000, false)
+	head, _ := newTestHead(t, 1000, false, false)
 	defer func() {
 		require.NoError(t, head.Close())
 	}()
@@ -2428,7 +2431,7 @@ func TestHeadShardedPostings(t *testing.T) {
 }
 
 func TestErrReuseAppender(t *testing.T) {
-	head, _ := newTestHead(t, 1000, false)
+	head, _ := newTestHead(t, 1000, false, false)
 	defer func() {
 		require.NoError(t, head.Close())
 	}()
@@ -2464,7 +2467,7 @@ func TestErrReuseAppender(t *testing.T) {
 
 func TestHeadMintAfterTruncation(t *testing.T) {
 	chunkRange := int64(2000)
-	head, _ := newTestHead(t, chunkRange, false)
+	head, _ := newTestHead(t, chunkRange, false, false)
 
 	app := head.Appender(context.Background())
 	_, err := app.Append(0, labels.Labels{{Name: "a", Value: "b"}}, 100, 100)
@@ -2498,7 +2501,7 @@ func TestHeadMintAfterTruncation(t *testing.T) {
 
 func TestHeadExemplars(t *testing.T) {
 	chunkRange := int64(2000)
-	head, _ := newTestHead(t, chunkRange, false)
+	head, _ := newTestHead(t, chunkRange, false, false)
 	app := head.Appender(context.Background())
 
 	l := labels.FromStrings("traceId", "123")
@@ -2520,7 +2523,7 @@ func TestHeadExemplars(t *testing.T) {
 
 func BenchmarkHeadLabelValuesWithMatchers(b *testing.B) {
 	chunkRange := int64(2000)
-	head, _ := newTestHead(b, chunkRange, false)
+	head, _ := newTestHead(b, chunkRange, false, false)
 	b.Cleanup(func() { require.NoError(b, head.Close()) })
 
 	app := head.Appender(context.Background())
@@ -2832,7 +2835,7 @@ func TestWaitForPendingReadersInTimeRange(t *testing.T) {
 }
 
 func TestChunkSnapshot(t *testing.T) {
-	head, _ := newTestHead(t, 120*4, false)
+	head, _ := newTestHead(t, 120*4, false, false)
 	defer func() {
 		head.opts.EnableMemorySnapshotOnShutdown = false
 		require.NoError(t, head.Close())
@@ -3074,7 +3077,7 @@ func TestChunkSnapshot(t *testing.T) {
 }
 
 func TestSnapshotError(t *testing.T) {
-	head, _ := newTestHead(t, 120*4, false)
+	head, _ := newTestHead(t, 120*4, false, false)
 	defer func() {
 		head.opts.EnableMemorySnapshotOnShutdown = false
 		require.NoError(t, head.Close())
@@ -3407,7 +3410,7 @@ func TestOOOMmapReplay(t *testing.T) {
 }
 
 func TestHeadInit_DiscardChunksWithUnsupportedEncoding(t *testing.T) {
-	h, _ := newTestHead(t, 1000, false)
+	h, _ := newTestHead(t, 1000, false, false)
 	defer func() {
 		require.NoError(t, h.Close())
 	}()

tsdb/ooo_head_read.go

@@ -134,6 +134,27 @@ func (oh *OOOHeadIndexReader) series(ref storage.SeriesRef, lbls *labels.Labels,
 	return nil
 }
 
+// PostingsForMatchers needs to be overridden so that the right IndexReader
+// implementation gets passed down to the PostingsForMatchers call.
+func (oh *OOOHeadIndexReader) PostingsForMatchers(concurrent bool, ms ...*labels.Matcher) (index.Postings, error) {
+	return oh.head.pfmc.PostingsForMatchers(oh, concurrent, ms...)
+}
+
+// LabelValues needs to be overridden from the headIndexReader implementation due
+// to the check that happens at the beginning where we make sure that the query
+// interval overlaps with the head minooot and maxooot.
+func (oh *OOOHeadIndexReader) LabelValues(name string, matchers ...*labels.Matcher) ([]string, error) {
+	if oh.maxt < oh.head.MinOOOTime() || oh.mint > oh.head.MaxOOOTime() {
+		return []string{}, nil
+	}
+
+	if len(matchers) == 0 {
+		return oh.head.postings.LabelValues(name), nil
+	}
+
+	return labelValuesWithMatchers(oh, name, matchers...)
+}
+
 type chunkMetaAndChunkDiskMapperRef struct {
 	meta     chunks.Meta
 	ref      chunks.ChunkDiskMapperRef

tsdb/ooo_head_read_test.go

@@ -3,6 +3,7 @@ package tsdb
 import (
 	"context"
 	"fmt"
+	"math"
 	"sort"
 	"testing"
 	"time"
@@ -280,7 +281,7 @@ func TestOOOHeadIndexReader_Series(t *testing.T) {
 		for perm, intervals := range permutations {
 			for _, headChunk := range []bool{false, true} {
 				t.Run(fmt.Sprintf("name=%s, permutation=%d, headChunk=%t", tc.name, perm, headChunk), func(t *testing.T) {
-					h, _ := newTestHead(t, 1000, false)
+					h, _ := newTestHead(t, 1000, false, true)
 					defer func() {
 						require.NoError(t, h.Close())
 					}()
@@ -357,6 +358,99 @@ func TestOOOHeadIndexReader_Series(t *testing.T) {
 	}
 }
 
+func TestOOOHeadChunkReader_LabelValues(t *testing.T) {
+	chunkRange := int64(2000)
+	head, _ := newTestHead(t, chunkRange, false, true)
+	t.Cleanup(func() { require.NoError(t, head.Close()) })
+
+	app := head.Appender(context.Background())
+
+	// Add in-order samples
+	_, err := app.Append(0, labels.Labels{
+		{Name: "foo", Value: "bar1"},
+	}, 100, 1)
+	require.NoError(t, err)
+	_, err = app.Append(0, labels.Labels{
+		{Name: "foo", Value: "bar2"},
+	}, 100, 2)
+	require.NoError(t, err)
+
+	// Add ooo samples for those series
+	_, err = app.Append(0, labels.Labels{
+		{Name: "foo", Value: "bar1"},
+	}, 90, 1)
+	require.NoError(t, err)
+	_, err = app.Append(0, labels.Labels{
+		{Name: "foo", Value: "bar2"},
+	}, 90, 2)
+	require.NoError(t, err)
+
+	require.NoError(t, app.Commit())
+
+	cases := []struct {
+		name       string
+		queryMinT  int64
+		queryMaxT  int64
+		expValues1 []string
+		expValues2 []string
+		expValues3 []string
+		expValues4 []string
+	}{
+		{
+			name:       "LabelValues calls when ooo head has max query range",
+			queryMinT:  math.MinInt64,
+			queryMaxT:  math.MaxInt64,
+			expValues1: []string{"bar1"},
+			expValues2: []string{},
+			expValues3: []string{"bar1", "bar2"},
+			expValues4: []string{"bar1", "bar2"},
+		},
+		{
+			name:       "LabelValues calls with ooo head query range not overlapping in-order data",
+			queryMinT:  90,
+			queryMaxT:  90,
+			expValues1: []string{"bar1"},
+			expValues2: []string{},
+			expValues3: []string{"bar1", "bar2"},
+			expValues4: []string{"bar1", "bar2"},
+		},
+		{
+			name:       "LabelValues calls with ooo head query range not overlapping out-of-order data",
+			queryMinT:  100,
+			queryMaxT:  100,
+			expValues1: []string{},
+			expValues2: []string{},
+			expValues3: []string{},
+			expValues4: []string{},
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			// We first want to test using a head index reader that covers the biggest query interval
+			oh := NewOOOHeadIndexReader(head, tc.queryMinT, tc.queryMaxT)
+			matchers := []*labels.Matcher{labels.MustNewMatcher(labels.MatchEqual, "foo", "bar1")}
+			values, err := oh.LabelValues("foo", matchers...)
+			require.NoError(t, err)
+			require.Equal(t, tc.expValues1, values)
+
+			matchers = []*labels.Matcher{labels.MustNewMatcher(labels.MatchNotRegexp, "foo", "^bar.")}
+			values, err = oh.LabelValues("foo", matchers...)
+			require.NoError(t, err)
+			require.Equal(t, tc.expValues2, values)
+
+			matchers = []*labels.Matcher{labels.MustNewMatcher(labels.MatchRegexp, "foo", "bar.")}
+			values, err = oh.LabelValues("foo", matchers...)
+			require.NoError(t, err)
+			require.Equal(t, tc.expValues3, values)
+
+			values, err = oh.LabelValues("foo")
+			require.NoError(t, err)
+			require.Equal(t, tc.expValues4, values)
+		})
+	}
+}
+
 // TestOOOHeadChunkReader_Chunk tests that the Chunk method works as expected.
 // It does so by appending out of order samples to the db and then initializing
 // an OOOHeadChunkReader to read chunks from it.