remove legacy

composer/utils/checkpoint.py

@@ -413,23 +413,6 @@ def format(self, state: State, is_deepspeed: bool = False, keep_placeholders: bo
                 ) + extra_suffix
 
 
-def is_checkpoint_legacy_sharded(object_store: Optional[Union[LoggerDestination, ObjectStore]], source_path: str):
-    if source_path.endswith('.symlink') or os.path.islink(source_path):
-        source_path = extract_path_from_symlink(source_path, object_store=object_store)
-    metadata_path = str(Path(source_path) / Path('.metadata'))
-    if object_store is None:
-        return not os.path.exists(metadata_path)
-    else:
-        try:
-            _, _, metadata_path = parse_uri(metadata_path)
-            with tempfile.TemporaryDirectory() as temp_dir:
-                metadata_destination = os.path.join(str(temp_dir), '.metadata')
-                download_object_or_file(metadata_path, metadata_destination, object_store)
-            return False
-        except FileNotFoundError:
-            return True
-
-
 def load_checkpoint(
     path: str,
     state: State,
@@ -531,15 +514,8 @@ def load_checkpoint(
             :attr:`load_weights_only` is not None. Otherwise, None.
     """
     path = partial_format(path, run_name=state.run_name)
-    using_legacy_sharded = False
-    if state.fsdp_sharded_state_dict_enabled:
-        assert object_store is None or isinstance(
-            object_store,
-            ObjectStore,
-        ), 'For loading sharded checkpoints load_object_store must be set with the class ObjectStore'
-        using_legacy_sharded = is_checkpoint_legacy_sharded(object_store, path)
 
-    if state.fsdp_sharded_state_dict_enabled and not using_legacy_sharded:
+    if state.fsdp_sharded_state_dict_enabled:
         rng_state_dicts = load_sharded_checkpoint(
             source_path=path,
             state=state,

tests/trainer/test_fsdp_checkpoint.py

@@ -31,7 +31,7 @@
 from composer.optim import DecoupledAdamW
 from composer.trainer import Trainer
 from composer.utils import FSDPConfig, TPConfig, dist, parse_uri
-from composer.utils.checkpoint import dist_cp_load, is_checkpoint_legacy_sharded
+from composer.utils.checkpoint import dist_cp_load
 from composer.utils.file_helpers import get_file
 from composer.utils.object_store import S3ObjectStore
 from composer.utils.reproducibility import get_rng_state
@@ -548,10 +548,6 @@ def test_fsdp_load_old_checkpoint(
             load_path_dir = (load_path_dir + 'ep0-ba2/')
 
         load_path = load_path_dir + f'ba2_rank{rank}.pt'
-        assert is_checkpoint_legacy_sharded(
-            object_store=S3ObjectStore(bucket=f'{s3_bucket}'),
-            source_path=load_path.lstrip(f's3://{s3_bucket}/'),
-        )
     else:
         load_path = (
             f's3://{s3_bucket}/{s3_read_only_prefix}/backwards_compatibility/'
@@ -909,16 +905,9 @@ def test_fsdp_partitioned_state_dict_load(
         load_path = 's3://' + save_folder.strip('s3://').format(
             run_name=run_name,
         ) + ('/ba2' if not use_symlink else '/latest-rank0.pt.symlink')
-        object_store = S3ObjectStore(bucket=f'{s3_bucket}')
     else:
-        object_store = None
         load_path = str(save_folder.format(run_name=run_name) / pathlib.Path('ba2'))
 
-    assert not is_checkpoint_legacy_sharded(
-        object_store=object_store,
-        source_path=load_path.replace(f's3://{s3_bucket}/', ''),
-    )
-
     if autoresume:
         load_path = None
     trainer2 = get_trainer(
@@ -1013,10 +1002,6 @@ def test_elastic_resumption(
     else:
         save_folder = None
         sharded_load_path = os.path.join(base_path, 'ba2')
-        assert not is_checkpoint_legacy_sharded(
-            object_store=S3ObjectStore(bucket=f'{s3_bucket}'),
-            source_path=sharded_load_path.replace(f's3://{s3_bucket}/', ''),
-        )
 
     sharded_trainer = get_trainer(
         save_folder=save_folder,
@@ -1237,11 +1222,6 @@ def set_up_planner(
 
     load_path = str(save_folder.format(run_name=run_name) / pathlib.Path('ba2'))
 
-    assert not is_checkpoint_legacy_sharded(
-        object_store=None,
-        source_path=load_path,
-    )
-
     trainer2 = get_trainer(
         save_folder=str(save_folder),
         load_path=load_path,