Replace sort.Slice with faster slices.SortFunc

The generic version is more efficient.

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

cmd/promtool/tsdb.go

@@ -23,7 +23,6 @@ import (
 	"path/filepath"
 	"runtime"
 	"runtime/pprof"
-	"sort"
 	"strconv"
 	"strings"
 	"sync"
@@ -34,6 +33,7 @@ import (
 	"github.com/prometheus/prometheus/storage"
 	"github.com/prometheus/prometheus/tsdb/chunkenc"
 	"github.com/prometheus/prometheus/tsdb/index"
+	"golang.org/x/exp/slices"
 
 	"github.com/alecthomas/units"
 	"github.com/go-kit/log"
@@ -447,7 +447,7 @@ func analyzeBlock(path, blockID string, limit int, runExtended bool) error {
 	postingInfos := []postingInfo{}
 
 	printInfo := func(postingInfos []postingInfo) {
-		sort.Slice(postingInfos, func(i, j int) bool { return postingInfos[i].metric > postingInfos[j].metric })
+		slices.SortFunc(postingInfos, func(a, b postingInfo) bool { return a.metric > b.metric })
 
 		for i, pc := range postingInfos {
 			if i >= limit {

rules/manager.go

@@ -19,7 +19,6 @@ import (
 	"fmt"
 	"math"
 	"net/url"
-	"sort"
 	"sync"
 	"time"
 
@@ -30,6 +29,7 @@ import (
 	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/codes"
+	"golang.org/x/exp/slices"
 
 	"github.com/prometheus/prometheus/model/labels"
 	"github.com/prometheus/prometheus/model/rulefmt"
@@ -490,10 +490,9 @@ func (g *Group) AlertingRules() []*AlertingRule {
 			alerts = append(alerts, alertingRule)
 		}
 	}
-	sort.Slice(alerts, func(i, j int) bool {
+	slices.SortFunc(alerts, func(a, b *AlertingRule) bool {
-		return alerts[i].State() > alerts[j].State() ||
+		return a.State() > b.State() ||
-			(alerts[i].State() == alerts[j].State() &&
+			(a.State() == b.State() && a.Name() < b.Name())
-				alerts[i].Name() < alerts[j].Name())
 	})
 	return alerts
 }
@@ -1189,11 +1188,11 @@ func (m *Manager) RuleGroups() []*Group {
 		rgs = append(rgs, g)
 	}
 
-	sort.Slice(rgs, func(i, j int) bool {
+	slices.SortFunc(rgs, func(a, b *Group) bool {
-		if rgs[i].file != rgs[j].file {
+		if a.file != b.file {
-			return rgs[i].file < rgs[j].file
+			return a.file < b.file
 		}
-		return rgs[i].name < rgs[j].name
+		return a.name < b.name
 	})
 
 	return rgs

scrape/scrape.go

@@ -23,7 +23,6 @@ import (
 	"math"
 	"net/http"
 	"reflect"
-	"sort"
 	"strconv"
 	"sync"
 	"time"
@@ -35,6 +34,7 @@ import (
 	config_util "github.com/prometheus/common/config"
 	"github.com/prometheus/common/model"
 	"github.com/prometheus/common/version"
+	"golang.org/x/exp/slices"
 
 	"github.com/prometheus/prometheus/config"
 	"github.com/prometheus/prometheus/discovery/targetgroup"
@@ -720,8 +720,8 @@ func mutateSampleLabels(lset labels.Labels, target *Target, honor bool, rc []*re
 }
 
 func resolveConflictingExposedLabels(lb *labels.Builder, conflictingExposedLabels []labels.Label) {
-	sort.SliceStable(conflictingExposedLabels, func(i, j int) bool {
+	slices.SortStableFunc(conflictingExposedLabels, func(a, b labels.Label) bool {
-		return len(conflictingExposedLabels[i].Name) < len(conflictingExposedLabels[j].Name)
+		return len(a.Name) < len(b.Name)
 	})
 
 	for _, l := range conflictingExposedLabels {

storage/remote/read_handler.go

@@ -16,12 +16,12 @@ package remote
 import (
 	"context"
 	"net/http"
-	"sort"
 	"sync"
 
 	"github.com/go-kit/log"
 	"github.com/go-kit/log/level"
 	"github.com/prometheus/client_golang/prometheus"
+	"golang.org/x/exp/slices"
 
 	"github.com/prometheus/prometheus/config"
 	"github.com/prometheus/prometheus/model/labels"
@@ -92,8 +92,8 @@ func (h *readHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 			Value: value,
 		})
 	}
-	sort.Slice(sortedExternalLabels, func(i, j int) bool {
+	slices.SortFunc(sortedExternalLabels, func(a, b prompb.Label) bool {
-		return sortedExternalLabels[i].Name < sortedExternalLabels[j].Name
+		return a.Name < b.Name
 	})
 
 	responseType, err := NegotiateResponseType(req.AcceptedResponseTypes)

tsdb/compact.go

@@ -20,7 +20,6 @@ import (
 	"io"
 	"os"
 	"path/filepath"
-	"sort"
 	"time"
 
 	"github.com/go-kit/log"
@@ -28,6 +27,7 @@ import (
 	"github.com/oklog/ulid"
 	"github.com/pkg/errors"
 	"github.com/prometheus/client_golang/prometheus"
+	"golang.org/x/exp/slices"
 
 	"github.com/prometheus/prometheus/storage"
 	"github.com/prometheus/prometheus/tsdb/chunkenc"
@@ -200,8 +200,8 @@ func (c *LeveledCompactor) Plan(dir string) ([]string, error) {
 }
 
 func (c *LeveledCompactor) plan(dms []dirMeta) ([]string, error) {
-	sort.Slice(dms, func(i, j int) bool {
+	slices.SortFunc(dms, func(a, b dirMeta) bool {
-		return dms[i].meta.MinTime < dms[j].meta.MinTime
+		return a.meta.MinTime < b.meta.MinTime
 	})
 
 	res := c.selectOverlappingDirs(dms)
@@ -380,8 +380,8 @@ func CompactBlockMetas(uid ulid.ULID, blocks ...*BlockMeta) *BlockMeta {
 	for s := range sources {
 		res.Compaction.Sources = append(res.Compaction.Sources, s)
 	}
-	sort.Slice(res.Compaction.Sources, func(i, j int) bool {
+	slices.SortFunc(res.Compaction.Sources, func(a, b ulid.ULID) bool {
-		return res.Compaction.Sources[i].Compare(res.Compaction.Sources[j]) < 0
+		return a.Compare(b) < 0
 	})
 
 	res.MinTime = mint

tsdb/db.go

@@ -22,7 +22,6 @@ import (
 	"math"
 	"os"
 	"path/filepath"
-	"sort"
 	"strconv"
 	"strings"
 	"sync"
@@ -34,6 +33,7 @@ import (
 	"github.com/pkg/errors"
 	"github.com/prometheus/client_golang/prometheus"
 	"go.uber.org/atomic"
+	"golang.org/x/exp/slices"
 	"golang.org/x/sync/errgroup"
 
 	"github.com/prometheus/prometheus/config"
@@ -579,8 +579,8 @@ func (db *DBReadOnly) Blocks() ([]BlockReader, error) {
 		return nil, nil
 	}
 
-	sort.Slice(loadable, func(i, j int) bool {
+	slices.SortFunc(loadable, func(a, b *Block) bool {
-		return loadable[i].Meta().MinTime < loadable[j].Meta().MinTime
+		return a.Meta().MinTime < b.Meta().MinTime
 	})
 
 	blockMetas := make([]BlockMeta, 0, len(loadable))
@@ -1445,8 +1445,8 @@ func (db *DB) reloadBlocks() (err error) {
 	}
 	db.metrics.blocksBytes.Set(float64(blocksSize))
 
-	sort.Slice(toLoad, func(i, j int) bool {
+	slices.SortFunc(toLoad, func(a, b *Block) bool {
-		return toLoad[i].Meta().MinTime < toLoad[j].Meta().MinTime
+		return a.Meta().MinTime < b.Meta().MinTime
 	})
 
 	// Swap new blocks first for subsequently created readers to be seen.
@@ -1515,8 +1515,8 @@ func deletableBlocks(db *DB, blocks []*Block) map[ulid.ULID]struct{} {
 
 	// Sort the blocks by time - newest to oldest (largest to smallest timestamp).
 	// This ensures that the retentions will remove the oldest  blocks.
-	sort.Slice(blocks, func(i, j int) bool {
+	slices.SortFunc(blocks, func(a, b *Block) bool {
-		return blocks[i].Meta().MaxTime > blocks[j].Meta().MaxTime
+		return a.Meta().MaxTime > b.Meta().MaxTime
 	})
 
 	for _, block := range blocks {

tsdb/exemplar.go

@@ -15,11 +15,11 @@ package tsdb
 
 import (
 	"context"
-	"sort"
 	"sync"
 	"unicode/utf8"
 
 	"github.com/prometheus/client_golang/prometheus"
+	"golang.org/x/exp/slices"
 
 	"github.com/prometheus/prometheus/config"
 	"github.com/prometheus/prometheus/model/exemplar"
@@ -185,8 +185,8 @@ func (ce *CircularExemplarStorage) Select(start, end int64, matchers ...[]*label
 		}
 	}
 
-	sort.Slice(ret, func(i, j int) bool {
+	slices.SortFunc(ret, func(a, b exemplar.QueryResult) bool {
-		return labels.Compare(ret[i].SeriesLabels, ret[j].SeriesLabels) < 0
+		return labels.Compare(a.SeriesLabels, b.SeriesLabels) < 0
 	})
 
 	return ret, nil

tsdb/head_read.go

@@ -137,8 +137,8 @@ func (h *headIndexReader) SortedPostings(p index.Postings) index.Postings {
 		return index.ErrPostings(errors.Wrap(err, "expand postings"))
 	}
 
-	sort.Slice(series, func(i, j int) bool {
+	slices.SortFunc(series, func(a, b *memSeries) bool {
-		return labels.Compare(series[i].lset, series[j].lset) < 0
+		return labels.Compare(a.lset, b.lset) < 0
 	})
 
 	// Convert back to list.

tsdb/index/postings.go

@@ -107,11 +107,11 @@ func (p *MemPostings) SortedKeys() []labels.Label {
 	}
 	p.mtx.RUnlock()
 
-	sort.Slice(keys, func(i, j int) bool {
+	slices.SortFunc(keys, func(a, b labels.Label) bool {
-		if keys[i].Name != keys[j].Name {
+		if a.Name != b.Name {
-			return keys[i].Name < keys[j].Name
+			return a.Name < b.Name
 		}
-		return keys[i].Value < keys[j].Value
+		return a.Value < b.Value
 	})
 	return keys
 }

tsdb/index/postingsstats.go

@@ -15,7 +15,8 @@ package index
 
 import (
 	"math"
-	"sort"
+
+	"golang.org/x/exp/slices"
 )
 
 // Stat holds values for a single cardinality statistic.
@@ -62,8 +63,8 @@ func (m *maxHeap) push(item Stat) {
 }
 
 func (m *maxHeap) get() []Stat {
-	sort.Slice(m.Items, func(i, j int) bool {
+	slices.SortFunc(m.Items, func(a, b Stat) bool {
-		return m.Items[i].Count > m.Items[j].Count
+		return a.Count > b.Count
 	})
 	return m.Items
 }

tsdb/wlog/checkpoint.go

@@ -20,13 +20,13 @@ import (
 	"math"
 	"os"
 	"path/filepath"
-	"sort"
 	"strconv"
 	"strings"
 
 	"github.com/go-kit/log"
 	"github.com/go-kit/log/level"
 	"github.com/pkg/errors"
+	"golang.org/x/exp/slices"
 
 	"github.com/prometheus/prometheus/tsdb/chunks"
 	tsdb_errors "github.com/prometheus/prometheus/tsdb/errors"
@@ -374,8 +374,8 @@ func listCheckpoints(dir string) (refs []checkpointRef, err error) {
 		refs = append(refs, checkpointRef{name: fi.Name(), index: idx})
 	}
 
-	sort.Slice(refs, func(i, j int) bool {
+	slices.SortFunc(refs, func(a, b checkpointRef) bool {
-		return refs[i].index < refs[j].index
+		return a.index < b.index
 	})
 
 	return refs, nil

tsdb/wlog/wlog.go

@@ -22,7 +22,6 @@ import (
 	"io"
 	"os"
 	"path/filepath"
-	"sort"
 	"strconv"
 	"sync"
 	"time"
@@ -32,6 +31,7 @@ import (
 	"github.com/golang/snappy"
 	"github.com/pkg/errors"
 	"github.com/prometheus/client_golang/prometheus"
+	"golang.org/x/exp/slices"
 
 	"github.com/prometheus/prometheus/tsdb/fileutil"
 )
@@ -859,8 +859,8 @@ func listSegments(dir string) (refs []segmentRef, err error) {
 		}
 		refs = append(refs, segmentRef{name: fn, index: k})
 	}
-	sort.Slice(refs, func(i, j int) bool {
+	slices.SortFunc(refs, func(a, b segmentRef) bool {
-		return refs[i].index < refs[j].index
+		return a.index < b.index
 	})
 	for i := 0; i < len(refs)-1; i++ {
 		if refs[i].index+1 != refs[i+1].index {