diff --git a/common/dice/dice_test.go b/common/dice/dice_test.go
new file mode 100644
index 00000000..09b1dd4d
--- /dev/null
+++ b/common/dice/dice_test.go
@@ -0,0 +1,32 @@
+package dice_test
+
+import (
+	"math/rand"
+	"testing"
+
+	. "v2ray.com/core/common/dice"
+)
+
+func BenchmarkRoll1(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		Roll(1)
+	}
+}
+
+func BenchmarkRoll20(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		Roll(20)
+	}
+}
+
+func BenchmarkIntn1(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		rand.Intn(1)
+	}
+}
+
+func BenchmarkIntn20(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		rand.Intn(20)
+	}
+}