From 9b2996a0ac7975309766bb1e460f5371b3903a7b Mon Sep 17 00:00:00 2001
From: Yufeng He <40085740+he-yufeng@users.noreply.github.com>
Date: Fri, 5 Jun 2026 16:29:20 +0800
Subject: [PATCH] fix: log eigenvalue monitor values

Signed-off-by: Yufeng He <40085740+he-yufeng@users.noreply.github.com>
---
 deepspeed/runtime/engine.py                  | 16 +++++++++-------
 tests/unit/runtime/test_engine_eigenvalue.py | 16 ++++++++++++++++
 2 files changed, 25 insertions(+), 7 deletions(-)
 create mode 100644 tests/unit/runtime/test_engine_eigenvalue.py

diff --git a/deepspeed/runtime/engine.py b/deepspeed/runtime/engine.py
index 82a7592f14cb..2cdd161a5125 100755
--- a/deepspeed/runtime/engine.py
+++ b/deepspeed/runtime/engine.py
@@ -205,6 +205,13 @@ def active_timers(self):
         return self.micro_timers + self.global_timers
 
 
+def _eigenvalue_summary_events(block_eigenvalue, global_samples):
+    return [
+        (f"Train/Eigenvalues/ModelBlockParam_{i}", ev_value[0], global_samples)
+        for i, ev_value in enumerate(block_eigenvalue.values())
+    ]
+
+
 class DeepSpeedEngine(Module):
     r"""DeepSpeed engine for training."""
 
@@ -2965,13 +2972,8 @@ def step(self, lr_kwargs=None):
 
                     if (self.eigenvalue_enabled()
                             and not self.gas_boundary_ctr % self.eigenvalue_gas_boundary_resolution()):
-                        ev_values = self.block_eigenvalue.values()
-                        for i in range(len(ev_values)):
-                            self.summary_events.append((
-                                f"Train/Eigenvalues/ModelBlockParam_{i}",
-                                self.ev_values[i][0],
-                                self.global_samples,
-                            ))
+                        self.summary_events.extend(
+                            _eigenvalue_summary_events(self.block_eigenvalue, self.global_samples))
                     self.monitor.write_events(self.summary_events)
 
         # Check flops profiling
diff --git a/tests/unit/runtime/test_engine_eigenvalue.py b/tests/unit/runtime/test_engine_eigenvalue.py
new file mode 100644
index 000000000000..c7f7e062eeb7
--- /dev/null
+++ b/tests/unit/runtime/test_engine_eigenvalue.py
@@ -0,0 +1,16 @@
+# Copyright (c) Microsoft Corporation.
+# SPDX-License-Identifier: Apache-2.0
+
+from deepspeed.runtime.engine import _eigenvalue_summary_events
+
+
+def test_eigenvalue_summary_events_use_block_values():
+    block_eigenvalue = {
+        "layer0.weight": (1.25, 0),
+        "layer1.weight": (0.5, 1),
+    }
+
+    assert _eigenvalue_summary_events(block_eigenvalue, global_samples=128) == [
+        ("Train/Eigenvalues/ModelBlockParam_0", 1.25, 128),
+        ("Train/Eigenvalues/ModelBlockParam_1", 0.5, 128),
+    ]