diff --git a/.gitignore b/.gitignore
index 53c37a1..c98e412 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,2 @@
-dist
\ No newline at end of file
+dist
+tests
\ No newline at end of file
diff --git a/README.md b/README.md
index d0eda72..a3f1712 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,6 @@
-# Logging with color and format string
\ No newline at end of file
+# Logging with color and format string
+
+## Test
+
+Mem: `go test -o tests/test.exe -memprofile tests/mem && go tool pprof -http : tests/mem`
+Cpu: `go test -o tests/test.exe -cpuprofile tests/cpu && go tool pprof -http : tests/cpu`
\ No newline at end of file
diff --git a/log.go b/log.go
index c6466b5..ef24528 100644
--- a/log.go
+++ b/log.go
@@ -86,8 +86,10 @@ type Logger struct {
 	err io.Writer
 	out io.Writer
 
-	formatter  *LogFormater
-	funcMap    template.FuncMap
+	formatter *LogFormater
+	funcMap   template.FuncMap
+
+	tmpl       *template.Template
 	err_tmpl   *template.Template
 	debug_tmpl *template.Template
 	warn_tmpl  *template.Template
@@ -115,10 +117,7 @@ func (l *Logger) Sub(sys string) *Logger {
 		color:     l.color,
 		formatter: l.formatter,
 
-		err_tmpl:   l.err_tmpl,
-		debug_tmpl: l.debug_tmpl,
-		warn_tmpl:  l.warn_tmpl,
-		info_tmpl:  l.info_tmpl,
+		tmpl: l.tmpl,
 	}
 	if l.subs == nil {
 		l.subs = make([]*Logger, 0)
@@ -209,26 +208,23 @@ func (l *Logger) ParseTmpl() error {
 	funcMap := copyFuncMap(l.funcMap)
 	l.setColorMap(funcMap)
 
-	err_tmpl, err := template.New("err_tmpl").Funcs(funcMap).Parse(l.formatter.ErrTmplStr)
+	tmpl, err := template.New("info_tmpl").Funcs(funcMap).Parse(l.formatter.InfoTmplStr)
 	if err != nil {
 		return err
 	}
-	l.err_tmpl = err_tmpl
-	warn_tmpl, err := template.New("warn_tmpl").Funcs(funcMap).Parse(l.formatter.WarnTmplStr)
+	tmpl, err = tmpl.New("err_tmpl").Parse(l.formatter.ErrTmplStr)
 	if err != nil {
 		return err
 	}
-	l.warn_tmpl = warn_tmpl
-	info_tmpl, err := template.New("info_tmpl").Funcs(funcMap).Parse(l.formatter.InfoTmplStr)
+	tmpl, err = tmpl.New("warn_tmpl").Parse(l.formatter.WarnTmplStr)
 	if err != nil {
 		return err
 	}
-	l.info_tmpl = info_tmpl
-	debug_tmpl, err := template.New("debug_tmpl").Funcs(funcMap).Parse(l.formatter.DebugTmplStr)
+	tmpl, err = tmpl.New("debug_tmpl").Parse(l.formatter.DebugTmplStr)
 	if err != nil {
 		return err
 	}
-	l.debug_tmpl = debug_tmpl
+	l.tmpl = tmpl
 	return nil
 }
 
@@ -257,22 +253,22 @@ func (l *Logger) output(t tout, depth int, stack string, fields H, v ...interfac
 		if LEVEL&Lerror == 0 {
 			return
 		}
-		err = l.err_tmpl.Execute(l.err, data)
+		err = l.tmpl.ExecuteTemplate(l.err, "err_tmpl", data)
 	case tdebug:
 		if LEVEL&Ldebug == 0 {
 			return
 		}
-		err = l.debug_tmpl.Execute(l.err, data)
+		err = l.tmpl.ExecuteTemplate(l.err, "debug_tmpl", data)
 	case twarn:
 		if LEVEL&Lwarn == 0 {
 			return
 		}
-		err = l.warn_tmpl.Execute(l.out, data)
+		err = l.tmpl.ExecuteTemplate(l.out, "warn_tmpl", data)
 	case tinfo:
 		if LEVEL&Linfo == 0 {
 			return
 		}
-		err = l.info_tmpl.Execute(l.out, data)
+		err = l.tmpl.ExecuteTemplate(l.out, "info_tmpl", data)
 	}
 	if err != nil {
 		fmt.Fprintln(l.err, "[FATAL] Logger error:", err)