Repository: huggingface/transformers
Pull request: fix the FSDP1 default for reshard_after_forward

# What does this PR do?

follow-up to #42566, for FSDP1, `reshard_after_forward` should be a sharding strategy instead of a bool

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Fixes # (issue)


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Changed files:
filename: src/transformers/training_args.py
patch: @@ -2755,7 +2755,7 @@ def _process_fsdp_args(self):
                 )
                 fsdp_plugin_args["backward_prefetch"] = prefetch_policy.upper()
                 fsdp_plugin_args["reshard_after_forward"] = str(
-                    self.fsdp_config.get("reshard_after_forward", "false")
+                    self.fsdp_config.get("reshard_after_forward", "FULL_SHARD")
                 ).lower()
                 fsdp_plugin_args["use_orig_params"] = str_to_bool(
                     str(self.fsdp_config.get("use_orig_params", "true")).lower()