fix mis-alignment column while using rich model summary in DeepSpeedstrategy (#21100)

* fix mis-alignment column while using rich model summary in DeepSpeed strategy.
* test: add minimum gpu requirement in `test_deepspeed_summary_with_rich_model_summary`
* chlog

---------

Co-authored-by: Jirka B <[email protected]>
Co-authored-by: Nicki Skafte Detlefsen <[email protected]>

Author: 3 people

src/lightning/pytorch/CHANGELOG.md

@@ -37,6 +37,8 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 - Fixed learning rate not being correctly set after using `LearningRateFinder` callback ([#21068](https://github.com/Lightning-AI/pytorch-lightning/pull/21068))
 
 
+- Fixed misalignment column while using rich model summary in `DeepSpeedstrategy` ([#21100](https://github.com/Lightning-AI/pytorch-lightning/pull/21100))
+
 ---
 
 ## [2.5.3] - 2025-08-13

src/lightning/pytorch/callbacks/rich_model_summary.py

@@ -79,18 +79,21 @@ def summarize(
         from rich.table import Table
 
         console = get_console()
+        column_names = list(zip(*summary_data))[0]
 
         header_style: str = summarize_kwargs.get("header_style", "bold magenta")
         table = Table(header_style=header_style)
         table.add_column(" ", style="dim")
         table.add_column("Name", justify="left", no_wrap=True)
         table.add_column("Type")
         table.add_column("Params", justify="right")
+
+        if "Params per Device" in column_names:
+            table.add_column("Params per Device", justify="right")
+
         table.add_column("Mode")
         table.add_column("FLOPs", justify="right")
 
-        column_names = list(zip(*summary_data))[0]
-
         for column_name in ["In sizes", "Out sizes"]:
             if column_name in column_names:
                 table.add_column(column_name, justify="right", style="white")

src/lightning/pytorch/utilities/model_summary/model_summary_deepspeed.py

@@ -99,6 +99,7 @@ def _get_summary_data(self) -> list[tuple[str, list[str]]]:
             ("Params", list(map(get_human_readable_count, self.param_nums))),
             ("Params per Device", list(map(get_human_readable_count, self.parameters_per_layer))),
             ("Mode", ["train" if mode else "eval" for mode in self.training_modes]),
+            ("FLOPs", list(map(get_human_readable_count, (sum(x.values()) for x in self.flop_counts.values())))),
         ]
         if self._model.example_input_array is not None:
             arrays.append(("In sizes", [str(x) for x in self.in_sizes]))

tests/tests_pytorch/utilities/test_deepspeed_model_summary.py

@@ -12,6 +12,10 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from unittest import mock
+
+import torch
+
 import lightning.pytorch as pl
 from lightning.pytorch import Callback, Trainer
 from lightning.pytorch.demos.boring_classes import BoringModel
@@ -51,3 +55,38 @@ def on_fit_start(self, trainer: "pl.Trainer", pl_module: "pl.LightningModule") -
     )
 
     trainer.fit(model)
+
+
+@RunIf(min_cuda_gpus=1, deepspeed=True, rich=True)
+@mock.patch("rich.table.Table.add_row", autospec=True)
+def test_deepspeed_summary_with_rich_model_summary(mock_table_add_row, tmp_path):
+    from lightning.pytorch.callbacks import RichModelSummary
+
+    model = BoringModel()
+    model.example_input_array = torch.randn(4, 32)
+
+    trainer = Trainer(
+        strategy=DeepSpeedStrategy(stage=3),
+        default_root_dir=tmp_path,
+        accelerator="gpu",
+        fast_dev_run=True,
+        devices=1,
+        enable_model_summary=True,
+        callbacks=[RichModelSummary()],
+    )
+
+    trainer.fit(model)
+
+    # assert that the input summary data was converted correctly
+    args, _ = mock_table_add_row.call_args_list[0]
+    assert args[1:] == (
+        "0",
+        "layer",
+        "Linear",
+        "66  ",
+        "66  ",
+        "train",
+        "512  ",
+        "[4, 32]",
+        "[4, 2]",
+    )