diff --git a/src/util/comparator_test.rs b/src/util/comparator_test.rs
index e1ad1b62b0e57ea8971d2b56564c216ccaf9e208..d6d311b8822e7fd7b289a6cabf13e5c2a2e2358e 100644
--- a/src/util/comparator_test.rs
+++ b/src/util/comparator_test.rs
@@ -20,12 +20,9 @@ mod test {
         let option_val = comp.compare(&Slice::from("a"), &Slice::from("ab"));
         assert_eq!(option_val.unwrap(), Ordering::Less);
 
-        // // todo  Slice 存在 bug 未修复
-        // let comp = BytewiseComparatorImpl::default();
-        // let option_val = comp.compare(&Slice::from("b"), &Slice::from("abcd"));
-        // assert_eq!(option_val.unwrap(), Ordering::Greater);
+        let option_val = comp.compare(&Slice::from("b"), &Slice::from("abcd"));
+        assert_eq!(option_val.unwrap(), Ordering::Greater);
 
-        let comp = BytewiseComparatorImpl::default();
         let option_val = comp.compare(&Slice::from("abcd"), &Slice::from("abcd"));
         assert_eq!(option_val.unwrap(), Ordering::Equal);
     }
diff --git a/src/util/slice.rs b/src/util/slice.rs
index 26ea8b17359ad73bd5484abfe492ba504dc74da5..6416db3ce863c7d2713b34f86cbaf72a3604b0d4 100644
--- a/src/util/slice.rs
+++ b/src/util/slice.rs
@@ -152,24 +152,20 @@ impl PartialEq for Slice {
 impl PartialOrd for Slice {
     /// 判断两个 slice 的大小关系
     fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
-        match self.size().partial_cmp(&other.size()) {
-            Some(Ordering::Equal) => {
-                let cmp = unsafe {
-                    memcmp(
-                        self.data.as_ptr() as *const i8,
-                        other.data.as_ptr() as *const i8,
-                        self.size(),
-                    )
-                };
-                if cmp == 0 {
-                    Some(Ordering::Equal)
-                } else if cmp > 0 {
-                    Some(Ordering::Greater)
-                } else {
-                    Some(Ordering::Less)
-                }
-            }
-            op => op
+        let min = self.size().min(other.size());
+        let cmp = unsafe {
+            memcmp(
+                self.data.as_ptr() as *const i8,
+                other.data.as_ptr() as *const i8,
+                min,
+            )
+        };
+        if cmp == 0 {
+            self.size().partial_cmp(&other.size())
+        } else if cmp > 0 {
+            Some(Ordering::Greater)
+        } else {
+            Some(Ordering::Less)
         }
     }
 }
diff --git a/src/util/slice_test.rs b/src/util/slice_test.rs
index a2e0ec5780b3916957f2eeb2538eeb116ff81c7f..9baf1d17fbf6e1fd0adf9c14d35919821e45acaa 100644
--- a/src/util/slice_test.rs
+++ b/src/util/slice_test.rs
@@ -88,7 +88,7 @@ mod test {
     #[test]
     fn test_merge2() {
         let mut a0 = Slice::from("123");
-        let mut a2 = Slice::from("456");
+        let a2 = Slice::from("456");
         a0.merge(a2, None);
         assert_eq!(String::from("123456"), String::from(a0));
     }