[Rhythm] Remove redudant live traces sort

CHANGELOG.md

@@ -22,6 +22,7 @@
 * [ENHANCEMENT] Update tempo operational dashboard for new block-builder and v2 traces api [#4559](https://github.com/grafana/tempo/pull/4559) (@mdisibio)
 * [ENHANCEMENT] Improve block-builder performance by flushing blocks concurrently [#4565](https://github.com/grafana/tempo/pull/4565) (@mdisibio)
 * [ENHANCEMENT] Improve block-builder performance [#4596](https://github.com/grafana/tempo/pull/4596) (@mdisibio)
+* [ENHANCEMENT] Improve block-builder performance by not using WAL stage [#4647](https://github.com/grafana/tempo/pull/4647) [#4671](https://github.com/grafana/tempo/pull/4671) (@mdisibio)
 * [ENHANCEMENT] Export new `tempo_ingest_group_partition_lag` metric from block-builders and metrics-generators [#4571](https://github.com/grafana/tempo/pull/4571) (@mdisibio)
 * [ENHANCEMENT] Use distroless base container images for improved security [#4556](https://github.com/grafana/tempo/pull/4556) (@carles-grafana)
 * [BUGFIX] Choose a default step for a gRPC streaming query range request if none is provided. [#4546](https://github.com/grafana/tempo/pull/4576) (@joe-elliott)

modules/blockbuilder/tenant_store.go

@@ -191,7 +191,6 @@ type chEntry struct {
 
 type liveTracesIter struct {
 	mtx        sync.Mutex
-	entries    []entry
 	liveTraces *livetraces.LiveTraces[[]byte]
 	ch         chan []chEntry
 	chBuf      []chEntry
@@ -200,20 +199,9 @@ type liveTracesIter struct {
 }
 
 func newLiveTracesIter(liveTraces *livetraces.LiveTraces[[]byte]) *liveTracesIter {
-	// Get the list of all traces sorted by ID
-	tids := make([]entry, 0, len(liveTraces.Traces))
-	for hash, t := range liveTraces.Traces {
-		tids = append(tids, entry{t.ID, hash})
-	}
-
-	slices.SortFunc(tids, func(a, b entry) int {
-		return bytes.Compare(a.id, b.id)
-	})
-
 	ctx, cancel := context.WithCancel(context.Background())
 
 	l := &liveTracesIter{
-		entries:    tids,
 		liveTraces: liveTraces,
 		ch:         make(chan []chEntry, 1),
 		cancel:     cancel,
@@ -254,16 +242,16 @@ func (i *liveTracesIter) iter(ctx context.Context) {
 	defer close(i.ch)
 
 	// Get the list of all traces sorted by ID
-	tids := make([]entry, 0, len(i.liveTraces.Traces))
+	entries := make([]entry, 0, len(i.liveTraces.Traces))
 	for hash, t := range i.liveTraces.Traces {
-		tids = append(tids, entry{t.ID, hash})
+		entries = append(entries, entry{t.ID, hash})
 	}
-	slices.SortFunc(tids, func(a, b entry) int {
+	slices.SortFunc(entries, func(a, b entry) int {
 		return bytes.Compare(a.id, b.id)
 	})
 
 	// Begin sending to channel in chunks to reduce channel overhead.
-	seq := slices.Chunk(i.entries, 10)
+	seq := slices.Chunk(entries, 10)
 	for entries := range seq {
 		output := make([]chEntry, 0, len(entries))
 

pkg/livetraces/livetraces_test.go

@@ -5,6 +5,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/grafana/tempo/pkg/tempopb"
 	v1 "github.com/grafana/tempo/pkg/tempopb/trace/v1"
 	"github.com/grafana/tempo/pkg/util/test"
 	"github.com/stretchr/testify/require"
@@ -45,3 +46,36 @@ func TestLiveTracesSizesAndLen(t *testing.T) {
 		require.Equal(t, expectedLen, lt.Len())
 	}
 }
+
+func BenchmarkLiveTracesWrite(b *testing.B) {
+	lt := New[*v1.ResourceSpans](func(rs *v1.ResourceSpans) uint64 { return uint64(rs.Size()) })
+
+	var traces []*tempopb.Trace
+	for i := 0; i < 100_000; i++ {
+		traces = append(traces, test.MakeTrace(1, nil))
+	}
+
+	b.ResetTimer()
+
+	for i := 0; i < b.N; i++ {
+		for _, tr := range traces {
+			lt.Push(tr.ResourceSpans[0].ScopeSpans[0].Spans[0].TraceId, tr.ResourceSpans[0], 0)
+		}
+	}
+}
+
+func BenchmarkLiveTracesRead(b *testing.B) {
+	lt := New[*v1.ResourceSpans](func(rs *v1.ResourceSpans) uint64 { return uint64(rs.Size()) })
+
+	for i := 0; i < 100_000; i++ {
+		tr := test.MakeTrace(1, nil)
+		lt.Push(tr.ResourceSpans[0].ScopeSpans[0].Spans[0].TraceId, tr.ResourceSpans[0], 0)
+	}
+
+	b.ResetTimer()
+
+	for i := 0; i < b.N; i++ {
+		// This won't anything, instead of will benchmark the map iteration performance.
+		lt.CutIdle(time.Now().Add(-time.Hour), false)
+	}
+}