diff --git a/src/deepxtrace/diagnose.py b/src/deepxtrace/diagnose.py
index e75051b..a9b8c55 100644
--- a/src/deepxtrace/diagnose.py
+++ b/src/deepxtrace/diagnose.py
@@ -117,6 +117,7 @@ class Diagnose:
         DEEPEP_DIAGNOSE_THRESHOLD_COL: determine threshold for abnormal columns. Default 3.0.
         DEEPEP_DIAGNOSE_THRESHOLD_ROW: determine threshold for abnormal rows. Default 3.0.
         DEEPEP_DIAGNOSE_THRESHOLD_POINT: determine threshold for abnormal individual points. Default 5.0.
+        DEEPEP_DIAGNOSE_EXCLUDING_ZEROS: controls whether excluding zeros in diagnose_matrix. Default 0.
 
     """
 
@@ -161,6 +162,8 @@ def __init__(
             os.getenv(
                 "DEEPEP_DIAGNOSE_THRESHOLD_POINT",
                 5.0))
+        self.excluding_zeros = int(
+            os.getenv("DEEPEP_DIAGNOSE_EXCLUDING_ZEROS", 0))
 
         # Initialize the diagnose
         self.group = group
@@ -306,7 +309,7 @@ def _setup_logger_internal(
     @staticmethod
     def diagnose_matrix(
         mat, thres_col=3.0, thres_row=3.0, thres_point=5.0,
-        suppress_points_in_strong_rowscols=True
+        suppress_points_in_strong_rowscols=True, excluding_zeros=0
     ):
         """
         Detect abnormal columns, rows, and individual points in a 2D wait-time matrix.
@@ -344,8 +347,17 @@ def diagnose_matrix(
         ]
 
         # 3. Check for abnormal single points
-        # z_all = (mat - mat.mean()) / (mat.std() + 1e-8)
-        z_all = mat / (mat.mean() + 1e-8)
+        if excluding_zeros == 0:
+            # z_all = (mat - mat.mean()) / (mat.std() + 1e-8)
+            z_all = mat / (mat.mean() + 1e-8)
+        elif excluding_zeros == 1:
+            nonzero_values = mat[mat != 0]
+            if len(nonzero_values) > 0:
+                mean_val = nonzero_values.mean()
+                z_all = mat / (mean_val + 1e-8)
+            else:
+                z_all = mat
+
         # Get all positions with z-score > threshold
         abnormal_points = [
             [i, j, mat[i, j], z_all[i, j]]
@@ -362,6 +374,7 @@ def diagnose_matrix(
                 [i, j, v, z] for [i, j, v, z] in abnormal_points
                 if i not in strong_rows and j not in strong_cols
             ]
+
         # 4. Return for automatic processing
         return {
             "abnormal_cols": abnormal_cols,
@@ -436,7 +449,7 @@ def _gather_diagnose_stats_internal(
                 stats_arr = torch.stack(self.gather_tensor, dim=0).numpy()
             for i, name in enumerate(["Dispatch", "Combine"]):
                 res = Diagnose.diagnose_matrix(
-                    stats_arr[:, i, :], thres_col=self.thres_col, thres_row=self.thres_row, thres_point=self.thres_point)
+                    stats_arr[:, i, :], thres_col=self.thres_col, thres_row=self.thres_row, thres_point=self.thres_point, excluding_zeros=self.excluding_zeros)
                 results.append(res)
                 self.logger.info(
                     f"[Diagnose] InstanceID: {self.instance_id} EPSize: {self.group_size}, diagnose: {res}, {name} Wait Recv Cost Per Token Matrix[src_rank, dst_rank]")
diff --git a/tests/test_diagnose.py b/tests/test_diagnose.py
index c8c4ea9..4cf2ff7 100644
--- a/tests/test_diagnose.py
+++ b/tests/test_diagnose.py
@@ -70,6 +70,41 @@ def setUp(self):
             [15, 17, 12, 18, 13, 13, 15, 14],
         ])
 
+        self.mc2_layered = np.array([
+            [169, 537, 530, 294, 173, 128, 139, 140,
+                40, 0, 0, 0, 0, 0, 0, 0],
+            [1617, 196, 207, 170, 187, 151, 887, 174,
+                0, 34, 0, 0, 0, 0, 0, 0],
+            [1626, 210, 194, 186, 174, 162, 864, 160,
+                0, 0, 31, 0, 0, 0, 0, 0],
+            [1635, 324, 341, 186, 178, 153, 866, 169,
+                0, 0, 0, 34, 0, 0, 0, 0],
+            [1635, 543, 534, 302, 176, 125, 847, 140,
+                0, 0, 0, 0, 33, 0, 0, 0],
+            [1712, 681, 671, 401, 232, 102, 877, 132,
+                0, 0, 0, 0, 0, 37, 0, 0],
+            [997, 656, 643, 382, 235, 172, 107, 146, 0,
+                0, 0, 0, 0, 0, 42, 0],
+            [1918, 941, 931, 652, 448, 314, 1064, 199,
+                0, 0, 0, 0, 0, 0, 0, 42],
+            [1480, 0, 0, 0, 0, 0, 0, 0, 167, 239, 343,
+                154, 148, 150, 155, 143],
+            [0, 46, 0, 0, 0, 0, 0, 0, 1599, 169, 237,
+                156, 149, 146, 860, 140],
+            [0, 0, 48, 0, 0, 0, 0, 0, 1610, 161, 168,
+                159, 150, 161, 846, 145],
+            [0, 0, 0, 41, 0, 0, 0, 0, 1687, 320, 452,
+                82, 139, 166, 875, 136],
+            [0, 0, 0, 0, 42, 0, 0, 0, 1802, 481, 616,
+                242, 168, 214, 918, 166],
+            [0, 0, 0, 0, 0, 35, 0, 0, 1746, 417, 559,
+                226, 171, 185, 903, 151],
+            [0, 0, 0, 0, 0, 0, 738, 0, 1011, 393, 529,
+                171, 150, 162, 176, 154],
+            [0, 0, 0, 0, 0, 0, 0, 36, 1866, 555, 693,
+                325, 211, 222, 965, 180]
+        ])
+
     def test_diagnose_row(self):
         res = ds.Diagnose.diagnose_matrix(self.abnormal_row)
         self.assertEqual(
@@ -105,6 +140,31 @@ def test_diagnose_point(self):
                 'abnormal_cols': [], 'abnormal_rows': [], 'abnormal_points': [
                     [3, 4, 125, 7.279344854723584]]})
 
+    def test_mc2_layered(self):
+        res = ds.Diagnose.diagnose_matrix(
+            mat=self.mc2_layered, excluding_zeros=0)
+        self.assertEqual(
+            res, {
+                'abnormal_cols': [
+                    [
+                        0, 799.3125, 3.2102414457222475]], 'abnormal_rows': [], 'abnormal_points': [
+                    [
+                        9, 8, 1599, 6.421988986422549], [
+                            10, 8, 1610, 6.466167772445468], [
+                                11, 8, 1687, 6.775419274605904], [
+                                    12, 8, 1802, 7.237288401209152], [
+                                        13, 8, 1746, 7.012378217819744], [
+                                            15, 8, 1866, 7.494328610797046]]})
+
+        res = ds.Diagnose.diagnose_matrix(
+            mat=self.mc2_layered, excluding_zeros=1)
+        self.assertEqual(res,
+                         {'abnormal_cols': [[0,
+                                             799.3125,
+                                             3.2102414457222475]],
+                          'abnormal_rows': [],
+                             'abnormal_points': []})
+
 
 if __name__ == '__main__':
     unittest.main()