Skip to content

fix checkpoint hook for standalone validation #1696

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
Marchematics wants to merge 2 commits into
base: main
Choose a base branch
from
Open

fix checkpoint hook for standalone validation #1696

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
6d25944
fix checkpoint hook for standalone validation
Marchematics Aug 30, 2026
5709fe0
format checkpoint hook test
Marchematics Aug 30, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
5 changes: 5 additions & 0 deletions mmengine/hooks/checkpoint_hook.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -326,6 +326,11 @@ def before_train(self, runner) -> None:
self.keep_ckpt_ids: deque = deque(keep_ckpt_ids,
self.max_keep_ckpts)

def before_val(self, runner) -> None:
"""Initialize checkpoint state when validation runs standalone."""
if not hasattr(self, 'file_backend'):
self.before_train(runner)

def after_train_epoch(self, runner) -> None:
"""Save the checkpoint and synchronize buffers after each epoch.

Expand Down
12 changes: 11 additions & 1 deletion tests/test_hooks/test_checkpoint_hook.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -336,7 +336,6 @@ def test_after_val_epoch(self):
petrel_client = MagicMock()
for by_epoch, cfg in [(True, self.epoch_based_cfg),
(False, self.iter_based_cfg)]:
isfile = MagicMock(return_value=True)
self.clear_work_dir()
with patch.dict(sys.modules, {'petrel_client': petrel_client}), \
patch('mmengine.fileio.backends.PetrelBackend.put') as put_mock, \
Expand All @@ -362,6 +361,17 @@ def test_after_val_epoch(self):
isfile.assert_called_once()
remove_mock.assert_called_once()

def test_before_val_initializes_save_best(self):
runner = self.build_runner(self.epoch_based_cfg)
checkpoint_hook = CheckpointHook(save_best='acc')

checkpoint_hook.before_val(runner)
checkpoint_hook.after_val_epoch(runner, {'acc': 0.5})

self.assertEqual(runner.message_hub.get_info('best_score'), 0.5)
self.assertTrue(
osp.isfile(osp.join(runner.work_dir, 'best_acc_epoch_0.pth')))

def test_after_train_epoch(self):
cfg = copy.deepcopy(self.epoch_based_cfg)
runner = self.build_runner(cfg)
Expand Down