use string builder grow to reduce memory allocations in logging pkg

Author: luckyxiaoqiang

logging/logging.go

@@ -31,6 +31,8 @@ const (
 
 var (
 	DefaultDirName = filepath.Join("logs", "csp")
+
+	defaultLogMsgBufferSize = 256
 )
 
 var (
@@ -117,6 +119,9 @@ func caller(depth int) (file string, line int) {
 
 func AssembleMsg(depth int, logLevel, msg string, err error, keysAndValues ...interface{}) string {
 	sb := strings.Builder{}
+	if defaultLogMsgBufferSize > 0 {
+		sb.Grow(defaultLogMsgBufferSize)
+	}
 	file, line := caller(depth)
 	timeStr := time.Now().Format("2006-01-02 15:04:05.520")
 	caller := fmt.Sprintf("%s:%d", file, line)

logging/logging_test.go

@@ -109,3 +109,21 @@ func Benchmark_LoggingDebug_With_Precheck(b *testing.B) {
 		}
 	}
 }
+
+func BenchmarkAssembleMsg(b *testing.B) {
+	defaultLogMsgBufferSize = 256
+	b.Run("assemble msg using string builder with grow", func(b *testing.B) {
+		b.ReportAllocs()
+		for i := 0; i < b.N; i++ {
+			AssembleMsg(2, "INFO", "test msg", nil, "k1", "v1", "k2", "v2")
+		}
+	})
+
+	defaultLogMsgBufferSize = 0
+	b.Run("assemble msg using string builder without grow", func(b *testing.B) {
+		b.ReportAllocs()
+		for i := 0; i < b.N; i++ {
+			AssembleMsg(2, "INFO", "test msg", nil, "k1", "v1", "k2", "v2")
+		}
+	})
+}