Improve RichProgreasBar speed performance

docs/source-pytorch/common/hooks.rst

@@ -59,7 +59,7 @@ important to understand. The following order is always used:
     ...
     Callback: Training is starting!
     Model: Training is starting!
-    Epoch 0/0  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 64/64 ...
+    Epoch 0/0  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 64/64 ...
 
 
 .. note::

src/lightning/pytorch/callbacks/progress/rich_progress.py

@@ -12,6 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 import math
+import time
 from collections.abc import Generator
 from dataclasses import dataclass
 from datetime import timedelta
@@ -22,13 +23,15 @@
 from typing_extensions import override
 
 import lightning.pytorch as pl
+from lightning.fabric.utilities.imports import _IS_INTERACTIVE
 from lightning.pytorch.callbacks.progress.progress_bar import ProgressBar
 from lightning.pytorch.utilities.imports import _RICH_AVAILABLE
 from lightning.pytorch.utilities.types import STEP_OUTPUT
 
 if _RICH_AVAILABLE:
     from rich import get_console, reconfigure
     from rich.console import Console, RenderableType
+    from rich.live import _RefreshThread as _RichRefreshThread
     from rich.progress import BarColumn, Progress, ProgressColumn, Task, TaskID, TextColumn
     from rich.progress_bar import ProgressBar as _RichProgressBar
     from rich.style import Style
@@ -66,9 +69,49 @@ class CustomInfiniteTask(Task):
         def time_remaining(self) -> Optional[float]:
             return None
 
+    class _RefreshThread(_RichRefreshThread):
+        def __init__(self, *args: Any, **kwargs: Any) -> None:
+            self.refresh_cond = False
+            super().__init__(*args, **kwargs)
+
+        def run(self) -> None:
+            while not self.done.is_set():
+                if self.refresh_cond:
+                    with self.live._lock:
+                        self.live.refresh()
+                    self.refresh_cond = False
+                time.sleep(1 / self.refresh_per_second)
+
     class CustomProgress(Progress):
         """Overrides ``Progress`` to support adding tasks that have an infinite total size."""
 
+        def start(self) -> None:
+            """Starts the progress display.
+
+            Notes
+            -----
+                This override is needed to support the custom refresh thread.
+
+            """
+            if self.live.auto_refresh:
+                self.live._refresh_thread = _RefreshThread(self.live, self.live.refresh_per_second)
+                self.live.auto_refresh = False
+            super().start()
+            if self.live._refresh_thread:
+                self.live.auto_refresh = True
+                self.live._refresh_thread.start()
+
+        def stop(self) -> None:
+            refresh_thread = self.live._refresh_thread
+            super().stop()
+            if refresh_thread:
+                refresh_thread.stop()
+                refresh_thread.join()
+
+        def soft_refresh(self) -> None:
+            if self.live.auto_refresh and isinstance(self.live._refresh_thread, _RefreshThread):
+                self.live._refresh_thread.refresh_cond = True
+
         def add_task(
             self,
             description: str,
@@ -239,8 +282,8 @@ class RichProgressBar(ProgressBar):
         trainer = Trainer(callbacks=RichProgressBar())
 
     Args:
-        refresh_rate: Determines at which rate (in number of batches) the progress bars get updated.
-            Set it to ``0`` to disable the display.
+        refresh_rate: Determines at which rate (per second) the progress bars get updated.
+            Set it to ``0`` to disable the display. Default: 100
         leave: Leaves the finished progress bar in the terminal at the end of the epoch. Default: False
         theme: Contains styles used to stylize the progress bar.
         console_kwargs: Args for constructing a `Console`
@@ -258,7 +301,7 @@ class RichProgressBar(ProgressBar):
 
     def __init__(
         self,
-        refresh_rate: int = 1,
+        refresh_rate: int = 100,
         leave: bool = False,
         theme: RichProgressBarTheme = RichProgressBarTheme(),
         console_kwargs: Optional[dict[str, Any]] = None,
@@ -356,17 +399,21 @@ def _init_progress(self, trainer: "pl.Trainer") -> None:
             self.progress = CustomProgress(
                 *self.configure_columns(trainer),
                 self._metric_component,
-                auto_refresh=False,
+                auto_refresh=True,
+                refresh_per_second=self.refresh_rate if self.is_enabled else 1,
                 disable=self.is_disabled,
                 console=self._console,
             )
             self.progress.start()
             # progress has started
             self._progress_stopped = False
 
-    def refresh(self) -> None:
+    def refresh(self, hard: bool = False) -> None:
         if self.progress:
-            self.progress.refresh()
+            if hard or _IS_INTERACTIVE:
+                self.progress.refresh()
+            else:
+                self.progress.soft_refresh()
 
     @override
     def on_train_start(self, trainer: "pl.Trainer", pl_module: "pl.LightningModule") -> None:
@@ -466,16 +513,16 @@ def _initialize_train_progress_bar_id(self) -> None:
         train_description = self._get_train_description(self.trainer.current_epoch)
         self.train_progress_bar_id = self._add_task(total_batches, train_description)
 
-    def _update(self, progress_bar_id: Optional["TaskID"], current: int, visible: bool = True) -> None:
+    def _update(
+        self,
+        progress_bar_id: Optional["TaskID"],
+        current: int,
+        visible: bool = True,
+        hard: bool = False,
+    ) -> None:
         if self.progress is not None and self.is_enabled and progress_bar_id is not None:
-            total = self.progress.tasks[progress_bar_id].total
-            assert total is not None
-            if not self._should_update(current, total):
-                return
             self.progress.update(progress_bar_id, completed=current, visible=visible)
-
-    def _should_update(self, current: int, total: Union[int, float]) -> bool:
-        return current % self.refresh_rate == 0 or current == total
+            self.refresh(hard=hard)
 
     @override
     def on_validation_epoch_end(self, trainer: "pl.Trainer", pl_module: "pl.LightningModule") -> None:
@@ -549,12 +596,13 @@ def on_train_batch_end(
             # can happen when resuming from a mid-epoch restart
             self._initialize_train_progress_bar_id()
         self._update(self.train_progress_bar_id, batch_idx + 1)
-        self._update_metrics(trainer, pl_module, batch_idx + 1)
+        self._update_metrics(trainer, pl_module)
         self.refresh()
 
     @override
     def on_train_epoch_end(self, trainer: "pl.Trainer", pl_module: "pl.LightningModule") -> None:
-        self._update_metrics(trainer, pl_module, total_batches=True)
+        self._update_metrics(trainer, pl_module)
+        self.refresh()
 
     @override
     def on_validation_batch_end(
@@ -576,7 +624,6 @@ def on_validation_batch_end(
         if self.val_progress_bar_id is None:
             return
         self._update(self.val_progress_bar_id, batch_idx + 1)
-        self.refresh()
 
     @override
     def on_test_batch_end(
@@ -591,7 +638,6 @@ def on_test_batch_end(
         if self.is_disabled or self.test_progress_bar_id is None:
             return
         self._update(self.test_progress_bar_id, batch_idx + 1)
-        self.refresh()
 
     @override
     def on_predict_batch_end(
@@ -606,7 +652,6 @@ def on_predict_batch_end(
         if self.is_disabled or self.predict_progress_bar_id is None:
             return
         self._update(self.predict_progress_bar_id, batch_idx + 1)
-        self.refresh()
 
     def _get_train_description(self, current_epoch: int) -> str:
         train_description = f"Epoch {current_epoch}"
@@ -643,17 +688,10 @@ def _update_metrics(
         self,
         trainer: "pl.Trainer",
         pl_module: "pl.LightningModule",
-        current: Optional[int] = None,
-        total_batches: bool = False,
     ) -> None:
         if not self.is_enabled or self._metric_component is None:
             return
 
-        if current is not None and not total_batches:
-            total = self.total_train_batches
-            if not self._should_update(current, total):
-                return
-
         metrics = self.get_metrics(trainer, pl_module)
         if self._metric_component:
             self._metric_component.update(metrics)

tests/tests_pytorch/callbacks/progress/test_rich_progress_bar.py

@@ -131,6 +131,9 @@ def test_rich_progress_bar_custom_theme():
         _, kwargs = mocks["ProcessingSpeedColumn"].call_args
         assert kwargs["style"] == theme.processing_speed
 
+        progress_bar.progress.live._refresh_thread.stop()
+        progress_bar.progress.live._refresh_thread.join()
+
 
 @RunIf(rich=True)
 def test_rich_progress_bar_keyboard_interrupt(tmp_path):
@@ -176,6 +179,8 @@ def configure_columns(self, trainer):
     assert progress_bar.progress.columns[0] == custom_column
     assert len(progress_bar.progress.columns) == 2
 
+    progress_bar.progress.stop()
+
 
 @RunIf(rich=True)
 @pytest.mark.parametrize(("leave", "reset_call_count"), ([(True, 0), (False, 3)]))
@@ -216,30 +221,27 @@ def test_rich_progress_bar_refresh_rate_disabled(progress_update, tmp_path):
 
 @RunIf(rich=True)
 @pytest.mark.parametrize(
-    ("refresh_rate", "train_batches", "val_batches", "expected_call_count"),
+    ("train_batches", "val_batches", "expected_call_count"),
     [
         # note: there is always one extra update at the very end (+1)
-        (3, 6, 6, 2 + 2 + 1),
-        (4, 6, 6, 2 + 2 + 1),
-        (7, 6, 6, 1 + 1 + 1),
-        (1, 2, 3, 2 + 3 + 1),
-        (1, 0, 0, 0 + 0),
-        (3, 1, 0, 1 + 0),
-        (3, 1, 1, 1 + 1 + 1),
-        (3, 5, 0, 2 + 0),
-        (3, 5, 2, 2 + 1 + 1),
-        (6, 5, 2, 1 + 1 + 1),
+        (6, 6, 6 + 6 + 1),
+        (2, 3, 2 + 3 + 1),
+        (0, 0, 0 + 0),
+        (1, 0, 1 + 0),
+        (1, 1, 1 + 1 + 1),
+        (5, 0, 5 + 0),
+        (5, 2, 5 + 2 + 1),
     ],
 )
-def test_rich_progress_bar_with_refresh_rate(tmp_path, refresh_rate, train_batches, val_batches, expected_call_count):
+def test_rich_progress_bar_update_counts(tmp_path, train_batches, val_batches, expected_call_count):
     model = BoringModel()
     trainer = Trainer(
         default_root_dir=tmp_path,
         num_sanity_val_steps=0,
         limit_train_batches=train_batches,
         limit_val_batches=val_batches,
         max_epochs=1,
-        callbacks=RichProgressBar(refresh_rate=refresh_rate),
+        callbacks=RichProgressBar(),
     )
 
     trainer.progress_bar_callback.on_train_start(trainer, model)
@@ -345,7 +347,8 @@ def training_step(self, *args, **kwargs):
 
     for key in ("loss", "v_num", "train_loss"):
         assert key in rendered[train_progress_bar_id][1]
-        assert key not in rendered[val_progress_bar_id][1]
+        if val_progress_bar_id in rendered:
+            assert key not in rendered[val_progress_bar_id][1]
 
 
 def test_rich_progress_bar_metrics_fast_dev_run(tmp_path):
@@ -359,7 +362,8 @@ def test_rich_progress_bar_metrics_fast_dev_run(tmp_path):
     val_progress_bar_id = progress_bar.val_progress_bar_id
     rendered = progress_bar.progress.columns[-1]._renderable_cache
     assert "v_num" not in rendered[train_progress_bar_id][1]
-    assert "v_num" not in rendered[val_progress_bar_id][1]
+    if val_progress_bar_id in rendered:
+        assert "v_num" not in rendered[val_progress_bar_id][1]
 
 
 @RunIf(rich=True)

tests/tests_pytorch/callbacks/progress/test_tqdm_progress_bar.py

@@ -320,17 +320,14 @@ def on_validation_epoch_end(self, *args):
 
 def test_tqdm_progress_bar_default_value(tmp_path):
     """Test that a value of None defaults to refresh rate 1."""
-    trainer = Trainer(default_root_dir=tmp_path)
+    trainer = Trainer(default_root_dir=tmp_path, callbacks=TQDMProgressBar())
     assert trainer.progress_bar_callback.refresh_rate == 1
 
 
 @mock.patch.dict(os.environ, {"COLAB_GPU": "1"})
 @patch("lightning.pytorch.trainer.connectors.callback_connector._RICH_AVAILABLE", False)
 def test_tqdm_progress_bar_value_on_colab(tmp_path):
     """Test that Trainer will override the default in Google COLAB."""
-    trainer = Trainer(default_root_dir=tmp_path)
-    assert trainer.progress_bar_callback.refresh_rate == 20
-
     trainer = Trainer(default_root_dir=tmp_path, callbacks=TQDMProgressBar())
     assert trainer.progress_bar_callback.refresh_rate == 20