Replace Sprintf with byebufferpool in ctx.String()

# Original fn using Sprintf
Benchmark_Ctx_String-24          3846717               318.0 ns/op           152 B/op          8 allocs/op
Benchmark_Ctx_String-24          3780208               315.9 ns/op           152 B/op          8 allocs/op
Benchmark_Ctx_String-24          3627513               315.1 ns/op           152 B/op          8 allocs/op
Benchmark_Ctx_String-24          3712863               317.4 ns/op           152 B/op          8 allocs/op

// Modified using bytebufferpool
Benchmark_Ctx_String-24          8131666               149.3 ns/op            96 B/op          5 allocs/op
Benchmark_Ctx_String-24          7626406               148.3 ns/op            96 B/op          5 allocs/op
Benchmark_Ctx_String-24          8194621               149.2 ns/op            96 B/op          5 allocs/op
Benchmark_Ctx_String-24          8297750               156.6 ns/op            96 B/op          5 allocs/op

ctx.go

@@ -1605,14 +1605,39 @@ func (c *DefaultCtx) Status(status int) Ctx {
 //
 // The returned value may be useful for logging.
 func (c *DefaultCtx) String() string {
-	return fmt.Sprintf(
-		"#%016X - %s <-> %s - %s %s",
-		c.fasthttp.ID(),
-		c.fasthttp.LocalAddr(),
-		c.fasthttp.RemoteAddr(),
-		c.fasthttp.Request.Header.Method(),
-		c.fasthttp.URI().FullURI(),
-	)
+	// Get buffer from pool
+	buf := bytebufferpool.Get()
+
+	// Start with the ID, converting it to a hex string without fmt.Sprintf
+	buf.WriteByte('#')
+	// Convert ID to hexadecimal
+	id := strconv.FormatUint(uint64(c.fasthttp.ID()), 16)
+	// Pad with leading zeros to ensure 16 characters
+	for i := 0; i < (16 - len(id)); i++ {
+		buf.WriteByte('0')
+	}
+	buf.WriteString(id)
+	buf.WriteString(" - ")
+
+	// Add local and remote addresses directly
+	buf.WriteString(c.fasthttp.LocalAddr().String())
+	buf.WriteString(" <-> ")
+	buf.WriteString(c.fasthttp.RemoteAddr().String())
+	buf.WriteString(" - ")
+
+	// Add method and URI
+	buf.Write(c.fasthttp.Request.Header.Method())
+	buf.WriteByte(' ')
+	buf.Write(c.fasthttp.URI().FullURI())
+
+	// Allocate string
+	str := buf.String()
+
+	// Reset buffer
+	buf.Reset()
+	bytebufferpool.Put(buf)
+
+	return str
 }
 
 // Type sets the Content-Type HTTP header to the MIME type specified by the file extension.

ctx_test.go

@@ -4631,6 +4631,20 @@ func Test_Ctx_String(t *testing.T) {
 	require.Equal(t, "#0000000000000000 - 0.0.0.0:0 <-> 0.0.0.0:0 - GET http:///", c.String())
 }
 
+// go test -v  -run=^$ -bench=Benchmark_Ctx_String -benchmem -count=4
+func Benchmark_Ctx_String(b *testing.B) {
+	var str string
+	app := New()
+	ctx := app.NewCtx(&fasthttp.RequestCtx{})
+	b.ReportAllocs()
+	b.ResetTimer()
+
+	for n := 0; n < b.N; n++ {
+		str = ctx.String()
+	}
+	require.Equal(b, "#0000000000000000 - 0.0.0.0:0 <-> 0.0.0.0:0 - GET http:///", str)
+}
+
 func TestCtx_ParamsInt(t *testing.T) {
 	// Create a test context and set some strings (or params)
 	// create a fake app to be used within this test