chore: reduce memory and allocations

util/logstash/log.go

@@ -28,11 +28,13 @@ func Size() int64 {
 type logger struct {
 	mu   sync.RWMutex
 	data *ring.Ring
+	size int
 }
 
 func New(size int) *logger {
 	return &logger{
-		data: ring.New(size),
+		data: ring.New(1),
+		size: size,
 	}
 }
 
@@ -44,6 +46,12 @@ func (l *logger) Write(p []byte) (n int, err error) {
 
 	if !strings.HasPrefix(string(p), "[cache ]") {
 		l.data.Value = element(string(p))
+
+		// dynamically grow the ring
+		if l.data.Len() < l.size {
+			l.data.Link(ring.New(1))
+		}
+
 		l.data = l.data.Next()
 	}
 
@@ -95,7 +103,7 @@ func (l *logger) All(areas []string, level jww.Threshold, count int) []string {
 	r := l.data
 	all := len(areas) == 0 && level == jww.LevelTrace
 
-	var res []string
+	res := make([]string, 0, r.Len())
 	for range r.Len() {
 		r = r.Next()
 		if e, ok := r.Value.(element); ok && e != "" && (all || e.match(areas, level)) {

util/logstash/log_test.go

@@ -7,13 +7,15 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
+var (
+	s1 = "[test1 ] TRACE test1"
+	s2 = "[test2 ] ERROR test2"
+	s3 = "[test1 ] TRACE test3"
+)
+
 func TestLog(t *testing.T) {
 	log := New(10)
 
-	s1 := "[test1 ] TRACE test1"
-	s2 := "[test2 ] ERROR test2"
-	s3 := "[test1 ] TRACE test3"
-
 	// old to new
 	log.Write([]byte(s1))
 	log.Write([]byte(s2))
@@ -33,3 +35,16 @@ func TestLog(t *testing.T) {
 	assert.Equal(t, idx, log.data, "data should not be changed after All() call")
 	assert.Equal(t, []string{"test1", "test2"}, log.Areas())
 }
+
+func BenchmarkLog(b *testing.B) {
+	log := New(10000)
+
+	// old to new
+	log.Write([]byte(s1))
+	log.Write([]byte(s2))
+	log.Write([]byte(s3))
+
+	for i := 0; i < b.N; i++ {
+		log.All(nil, jww.LevelTrace, 1)
+	}
+}