Replace sort.Sort with faster slices.SortFunc

The generic version is more efficient.

Signed-off-by: Bryan Boreham <bjboreham@gmail.com>

promql/quantile.go

@@ -17,6 +17,8 @@ import (
 	"math"
 	"sort"
 
+	"golang.org/x/exp/slices"
+
 	"github.com/prometheus/prometheus/model/histogram"
 	"github.com/prometheus/prometheus/model/labels"
 )
@@ -38,10 +40,6 @@ type bucket struct {
 // buckets implements sort.Interface.
 type buckets []bucket
 
-func (b buckets) Len() int           { return len(b) }
-func (b buckets) Swap(i, j int)      { b[i], b[j] = b[j], b[i] }
-func (b buckets) Less(i, j int) bool { return b[i].upperBound < b[j].upperBound }
-
 type metricWithBuckets struct {
 	metric  labels.Labels
 	buckets buckets
@@ -83,7 +81,9 @@ func bucketQuantile(q float64, buckets buckets) float64 {
 	if q > 1 {
 		return math.Inf(+1)
 	}
-	sort.Sort(buckets)
+	slices.SortFunc(buckets, func(a, b bucket) bool {
+		return a.upperBound < b.upperBound
+	})
 	if !math.IsInf(buckets[len(buckets)-1].upperBound, +1) {
 		return math.NaN()
 	}

storage/remote/codec.go

@@ -26,6 +26,7 @@ import (
 	"github.com/gogo/protobuf/proto"
 	"github.com/golang/snappy"
 	"github.com/prometheus/common/model"
+	"golang.org/x/exp/slices"
 
 	"github.com/prometheus/prometheus/model/exemplar"
 	"github.com/prometheus/prometheus/model/histogram"
@@ -178,7 +179,9 @@ func FromQueryResult(sortSeries bool, res *prompb.QueryResult) storage.SeriesSet
 	}
 
 	if sortSeries {
-		sort.Sort(byLabel(series))
+		slices.SortFunc(series, func(a, b storage.Series) bool {
+			return labels.Compare(a.Labels(), b.Labels()) < 0
+		})
 	}
 	return &concreteSeriesSet{
 		series: series,
@@ -313,12 +316,6 @@ func MergeLabels(primary, secondary []prompb.Label) []prompb.Label {
 	return result
 }
 
-type byLabel []storage.Series
-
-func (a byLabel) Len() int           { return len(a) }
-func (a byLabel) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
-func (a byLabel) Less(i, j int) bool { return labels.Compare(a[i].Labels(), a[j].Labels()) < 0 }
-
 // errSeriesSet implements storage.SeriesSet, just returning an error.
 type errSeriesSet struct {
 	err error

tsdb/head_read.go

@@ -450,7 +450,7 @@ func (s *memSeries) oooMergedChunk(meta chunks.Meta, cdm *chunks.ChunkDiskMapper
 
 	// Next we want to sort all the collected chunks by min time so we can find
 	// those that overlap and stop when we know the rest don't.
-	sort.Sort(byMinTimeAndMinRef(tmpChks))
+	slices.SortFunc(tmpChks, refLessByMinTimeAndMinRef)
 
 	mc := &mergedOOOChunks{}
 	absoluteMax := int64(math.MinInt64)

tsdb/index/index.go

@@ -924,7 +924,7 @@ func (w *Writer) writePostingsToTmpFiles() error {
 				values = append(values, v)
 			}
 			// Symbol numbers are in order, so the strings will also be in order.
-			sort.Sort(uint32slice(values))
+			slices.Sort(values)
 			for _, v := range values {
 				value, err := w.symbols.Lookup(v)
 				if err != nil {
@@ -1017,12 +1017,6 @@ func (w *Writer) writePostings() error {
 	return nil
 }
 
-type uint32slice []uint32
-
-func (s uint32slice) Len() int           { return len(s) }
-func (s uint32slice) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
-func (s uint32slice) Less(i, j int) bool { return s[i] < s[j] }
-
 type labelIndexHashEntry struct {
 	keys   []string
 	offset uint64

tsdb/ooo_head_read.go

@@ -17,7 +17,8 @@ package tsdb
 import (
 	"errors"
 	"math"
-	"sort"
+
+	"golang.org/x/exp/slices"
 
 	"github.com/prometheus/prometheus/model/labels"
 	"github.com/prometheus/prometheus/storage"
@@ -130,7 +131,7 @@ func (oh *OOOHeadIndexReader) series(ref storage.SeriesRef, builder *labels.Scra
 
 	// Next we want to sort all the collected chunks by min time so we can find
 	// those that overlap.
-	sort.Sort(metaByMinTimeAndMinRef(tmpChks))
+	slices.SortFunc(tmpChks, lessByMinTimeAndMinRef)
 
 	// Next we want to iterate the sorted collected chunks and only return the
 	// chunks Meta the first chunk that overlaps with others.
@@ -175,30 +176,20 @@ type chunkMetaAndChunkDiskMapperRef struct {
 	origMaxT int64
 }
 
-type byMinTimeAndMinRef []chunkMetaAndChunkDiskMapperRef
-
-func (b byMinTimeAndMinRef) Len() int { return len(b) }
-func (b byMinTimeAndMinRef) Less(i, j int) bool {
-	if b[i].meta.MinTime == b[j].meta.MinTime {
-		return b[i].meta.Ref < b[j].meta.Ref
+func refLessByMinTimeAndMinRef(a, b chunkMetaAndChunkDiskMapperRef) bool {
+	if a.meta.MinTime == b.meta.MinTime {
+		return a.meta.Ref < b.meta.Ref
 	}
-	return b[i].meta.MinTime < b[j].meta.MinTime
+	return a.meta.MinTime < b.meta.MinTime
 }
 
-func (b byMinTimeAndMinRef) Swap(i, j int) { b[i], b[j] = b[j], b[i] }
-
-type metaByMinTimeAndMinRef []chunks.Meta
-
-func (b metaByMinTimeAndMinRef) Len() int { return len(b) }
-func (b metaByMinTimeAndMinRef) Less(i, j int) bool {
-	if b[i].MinTime == b[j].MinTime {
-		return b[i].Ref < b[j].Ref
+func lessByMinTimeAndMinRef(a, b chunks.Meta) bool {
+	if a.MinTime == b.MinTime {
+		return a.Ref < b.Ref
 	}
-	return b[i].MinTime < b[j].MinTime
+	return a.MinTime < b.MinTime
 }
 
-func (b metaByMinTimeAndMinRef) Swap(i, j int) { b[i], b[j] = b[j], b[i] }
-
 func (oh *OOOHeadIndexReader) Postings(name string, values ...string) (index.Postings, error) {
 	switch len(values) {
 	case 0:

tsdb/ooo_head_read_test.go

@@ -22,6 +22,7 @@ import (
 	"time"
 
 	"github.com/stretchr/testify/require"
+	"golang.org/x/exp/slices"
 
 	"github.com/prometheus/prometheus/model/labels"
 	"github.com/prometheus/prometheus/storage"
@@ -337,7 +338,7 @@ func TestOOOHeadIndexReader_Series(t *testing.T) {
 						}
 						expChunks = append(expChunks, meta)
 					}
-					sort.Sort(metaByMinTimeAndMinRef(expChunks)) // we always want the chunks to come back sorted by minTime asc
+					slices.SortFunc(expChunks, lessByMinTimeAndMinRef) // We always want the chunks to come back sorted by minTime asc.
 
 					if headChunk && len(intervals) > 0 {
 						// Put the last interval in the head chunk
@@ -1116,7 +1117,7 @@ func TestSortByMinTimeAndMinRef(t *testing.T) {
 
 	for _, tc := range tests {
 		t.Run(fmt.Sprintf("name=%s", tc.name), func(t *testing.T) {
-			sort.Sort(byMinTimeAndMinRef(tc.input))
+			slices.SortFunc(tc.input, refLessByMinTimeAndMinRef)
 			require.Equal(t, tc.exp, tc.input)
 		})
 	}
@@ -1180,7 +1181,7 @@ func TestSortMetaByMinTimeAndMinRef(t *testing.T) {
 
 	for _, tc := range tests {
 		t.Run(fmt.Sprintf("name=%s", tc.name), func(t *testing.T) {
-			sort.Sort(metaByMinTimeAndMinRef(tc.inputMetas))
+			slices.SortFunc(tc.inputMetas, lessByMinTimeAndMinRef)
 			require.Equal(t, tc.expMetas, tc.inputMetas)
 		})
 	}

util/stats/timer.go

@@ -16,8 +16,9 @@ package stats
 import (
 	"bytes"
 	"fmt"
-	"sort"
 	"time"
+
+	"golang.org/x/exp/slices"
 )
 
 // A Timer that can be started and stopped and accumulates the total time it
@@ -78,35 +79,17 @@ func (t *TimerGroup) GetTimer(name fmt.Stringer) *Timer {
 	return timer
 }
 
-// Timers is a slice of Timer pointers that implements Len and Swap from
-// sort.Interface.
-type Timers []*Timer
-
-type byCreationTimeSorter struct{ Timers }
-
-// Len implements sort.Interface.
-func (t Timers) Len() int {
-	return len(t)
-}
-
-// Swap implements sort.Interface.
-func (t Timers) Swap(i, j int) {
-	t[i], t[j] = t[j], t[i]
-}
-
-func (s byCreationTimeSorter) Less(i, j int) bool {
-	return s.Timers[i].created < s.Timers[j].created
-}
-
 // Return a string representation of a TimerGroup.
 func (t *TimerGroup) String() string {
-	timers := byCreationTimeSorter{}
+	timers := make([]*Timer, 0, len(t.timers))
 	for _, timer := range t.timers {
-		timers.Timers = append(timers.Timers, timer)
+		timers = append(timers, timer)
 	}
-	sort.Sort(timers)
+	slices.SortFunc(timers, func(a, b *Timer) bool {
+		return a.created < b.created
+	})
 	result := &bytes.Buffer{}
-	for _, timer := range timers.Timers {
+	for _, timer := range timers {
 		fmt.Fprintf(result, "%s\n", timer)
 	}
 	return result.String()

web/federate.go

@@ -25,6 +25,7 @@ import (
 	dto "github.com/prometheus/client_model/go"
 	"github.com/prometheus/common/expfmt"
 	"github.com/prometheus/common/model"
+	"golang.org/x/exp/slices"
 
 	"github.com/prometheus/prometheus/model/histogram"
 	"github.com/prometheus/prometheus/model/labels"
@@ -166,7 +167,11 @@ Loop:
 		return
 	}
 
-	sort.Sort(byName(vec))
+	slices.SortFunc(vec, func(a, b promql.Sample) bool {
+		ni := a.Metric.Get(labels.MetricName)
+		nj := b.Metric.Get(labels.MetricName)
+		return ni < nj
+	})
 
 	externalLabels := h.config.GlobalConfig.ExternalLabels.Map()
 	if _, ok := externalLabels[model.InstanceLabel]; !ok {
@@ -313,15 +318,3 @@ Loop:
 		}
 	}
 }
-
-// byName makes a model.Vector sortable by metric name.
-type byName promql.Vector
-
-func (vec byName) Len() int      { return len(vec) }
-func (vec byName) Swap(i, j int) { vec[i], vec[j] = vec[j], vec[i] }
-
-func (vec byName) Less(i, j int) bool {
-	ni := vec[i].Metric.Get(labels.MetricName)
-	nj := vec[j].Metric.Get(labels.MetricName)
-	return ni < nj
-}