diff --git a/metanode/util_test.go b/metanode/util_test.go
new file mode 100644
index 000000000..0b457876a
--- /dev/null
+++ b/metanode/util_test.go
@@ -0,0 +1,178 @@
+package metanode
+
+import (
+	"os"
+	"testing"
+	"time"
+)
+
+// mockFileInfo implements os.FileInfo for testing
+type mockFileInfo struct {
+	name  string
+	isDir bool
+}
+
+func (m mockFileInfo) Name() string       { return m.name }
+func (m mockFileInfo) IsDir() bool        { return m.isDir }
+func (m mockFileInfo) Size() int64        { return 0 }
+func (m mockFileInfo) Mode() os.FileMode  { return 0 }
+func (m mockFileInfo) ModTime() time.Time { return time.Time{} }
+func (m mockFileInfo) Sys() interface{}   { return nil }
+
+func TestDelExtFile_GetIdx(t *testing.T) {
+	tests := []struct {
+		name        string
+		input       string
+		expected    int64
+		expectPanic bool
+	}{
+		{
+			name:        "valid file name",
+			input:       "EXTENT_DEL_1",
+			expected:    1,
+			expectPanic: false,
+		},
+		{
+			name:        "valid file name with multiple digits",
+			input:       "EXTENT_DEL_12345",
+			expected:    12345,
+			expectPanic: false,
+		},
+		{
+			name:        "file name without underscore - should panic",
+			input:       "EXTENTDEL",
+			expected:    0,
+			expectPanic: true,
+		},
+		{
+			name:        "file name with non-numeric index - should panic",
+			input:       "EXTENT_DEL_abc",
+			expected:    0,
+			expectPanic: true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			defer func() {
+				r := recover()
+				if tt.expectPanic && r == nil {
+					t.Errorf("getDelExtFileIdx(%q) expected panic, but didn't panic", tt.input)
+				}
+				if !tt.expectPanic && r != nil {
+					t.Errorf("getDelExtFileIdx(%q) unexpected panic: %v", tt.input, r)
+				}
+			}()
+
+			result := getDelExtFileIdx(tt.input)
+			if !tt.expectPanic && result != tt.expected {
+				t.Errorf("getDelExtFileIdx(%q) = %d, expected %d", tt.input, result, tt.expected)
+			}
+		})
+	}
+}
+
+func TestDelExtFile_Len(t *testing.T) {
+	files := DelExtFile{
+		mockFileInfo{name: "EXTENT_DEL_1", isDir: false},
+		mockFileInfo{name: "EXTENT_DEL_2", isDir: false},
+	}
+
+	if files.Len() != 2 {
+		t.Errorf("DelExtFile.Len() = %d, expected 2", files.Len())
+	}
+}
+
+func TestDelExtFile_Swap(t *testing.T) {
+	files := DelExtFile{
+		mockFileInfo{name: "EXTENT_DEL_1", isDir: false},
+		mockFileInfo{name: "EXTENT_DEL_2", isDir: false},
+	}
+
+	originalFirst := files[0]
+	originalSecond := files[1]
+
+	files.Swap(0, 1)
+
+	if files[0] != originalSecond {
+		t.Errorf("Swap(0, 1) failed: first element should be %v, got %v", originalSecond, files[0])
+	}
+	if files[1] != originalFirst {
+		t.Errorf("Swap(0, 1) failed: second element should be %v, got %v", originalFirst, files[1])
+	}
+}
+
+func TestDelExtFile_Less(t *testing.T) {
+	files := DelExtFile{
+		mockFileInfo{name: "EXTENT_DEL_1", isDir: false},
+		mockFileInfo{name: "EXTENT_DEL_2", isDir: false},
+	}
+
+	if !files.Less(0, 1) {
+		t.Errorf("DelExtFile.Less(0, 1) should return true")
+	}
+
+	if files.Less(1, 0) {
+		t.Errorf("DelExtFile.Less(1, 0) should return false")
+	}
+}
+
+func TestDelExtFile_Sort(t *testing.T) {
+	// Test with valid files
+	files := []os.FileInfo{
+		mockFileInfo{name: "EXTENT_DEL_3", isDir: false},
+		mockFileInfo{name: "EXTENT_DEL_1", isDir: false},
+		mockFileInfo{name: "EXTENT_DEL_2", isDir: false},
+	}
+
+	result := sortDelExtFileInfo(files)
+
+	if len(result) != 3 {
+		t.Errorf("sortDelExtFileInfo() returned %d files, expected 3", len(result))
+		return
+	}
+
+	expected := []string{"EXTENT_DEL_1", "EXTENT_DEL_2", "EXTENT_DEL_3"}
+	for i, file := range result {
+		if file.Name() != expected[i] {
+			t.Errorf("sortDelExtFileInfo() result[%d] = %s, expected %s", i, file.Name(), expected[i])
+		}
+	}
+}
+
+func TestDelExtFile_SortWithDirectories(t *testing.T) {
+	// Test filtering out directories
+	files := []os.FileInfo{
+		mockFileInfo{name: "EXTENT_DEL_2", isDir: false},
+		mockFileInfo{name: "some_directory", isDir: true},
+		mockFileInfo{name: "EXTENT_DEL_1", isDir: false},
+	}
+
+	result := sortDelExtFileInfo(files)
+
+	if len(result) != 2 {
+		t.Errorf("sortDelExtFileInfo() returned %d files, expected 2", len(result))
+		return
+	}
+
+	expected := []string{"EXTENT_DEL_1", "EXTENT_DEL_2"}
+	for i, file := range result {
+		if file.Name() != expected[i] {
+			t.Errorf("sortDelExtFileInfo() result[%d] = %s, expected %s", i, file.Name(), expected[i])
+		}
+	}
+}
+
+func TestDelExtFile_SortEmptyInput(t *testing.T) {
+	// Test with empty input
+	result := sortDelExtFileInfo([]os.FileInfo{})
+	if len(result) != 0 {
+		t.Errorf("sortDelExtFileInfo() with empty input returned %d files, expected 0", len(result))
+	}
+
+	// Test with nil input
+	result = sortDelExtFileInfo(nil)
+	if len(result) != 0 {
+		t.Errorf("sortDelExtFileInfo() with nil input returned %d files, expected 0", len(result))
+	}
+}
diff --git a/raftstore/partition.go b/raftstore/partition.go
index 978af174f..0583d08ce 100644
--- a/raftstore/partition.go
+++ b/raftstore/partition.go
@@ -79,12 +79,6 @@ type Partition interface {
 
 	// CloseAndBackup closes the partition and backs up the WAL.
 	CloseAndBackup() error
-
-	// GetID returns the partition ID
-	GetID() uint64
-
-	// GetWalPath returns the WAL path
-	GetWalPath() string
 	Closed() bool
 }
 
@@ -96,16 +90,6 @@ type partition struct {
 	config  *PartitionConfig
 }
 
-// GetID returns the partition ID
-func (p *partition) GetID() uint64 {
-	return p.id
-}
-
-// GetWalPath returns the WAL path
-func (p *partition) GetWalPath() string {
-	return p.walPath
-}
-
 // ChangeMember submits member change event and information to raft log.
 func (p *partition) ChangeMember(changeType proto.ConfChangeType, peer proto.Peer, context []byte) (
 	resp interface{}, err error,