diff --git a/colossalai/booster/plugin/low_level_zero_plugin.py b/colossalai/booster/plugin/low_level_zero_plugin.py
index 761947344..16bb2e9b8 100644
--- a/colossalai/booster/plugin/low_level_zero_plugin.py
+++ b/colossalai/booster/plugin/low_level_zero_plugin.py
@@ -141,7 +141,9 @@ class LowLevelZeroCheckpointIO(TorchDDPCheckpointIO):
 
                 from colossalai.utils.safetensors import save_nested
 
-                f_writer = AsyncFileWriter(fp=open(checkpoint, "wb"), n_entries=self.N_WRITE_ENTRIES, backend="pthread")
+                f_writer = AsyncFileWriter(
+                    fp=open(checkpoint, "wb", buffering=0), n_entries=self.N_WRITE_ENTRIES, backend="pthread"
+                )
                 save_nested(f_writer, state_dict)
                 self.async_writers.append(f_writer)
             else:
@@ -225,7 +227,9 @@ class LowLevelZeroCheckpointIO(TorchDDPCheckpointIO):
                     from colossalai.utils.safetensors import save_nested
 
                     f_writer = AsyncFileWriter(
-                        fp=open(checkpoint_file_path, "wb"), n_entries=self.N_WRITE_ENTRIES, backend="pthread"
+                        fp=open(checkpoint_file_path, "wb", buffering=0),
+                        n_entries=self.N_WRITE_ENTRIES,
+                        backend="pthread",
                     )
                     save_nested(f_writer, shard)
                     self.async_writers.append(f_writer)
diff --git a/colossalai/checkpoint_io/general_checkpoint_io.py b/colossalai/checkpoint_io/general_checkpoint_io.py
index a2d1dd158..ddfe5502f 100644
--- a/colossalai/checkpoint_io/general_checkpoint_io.py
+++ b/colossalai/checkpoint_io/general_checkpoint_io.py
@@ -56,7 +56,7 @@ class GeneralCheckpointIO(CheckpointIO):
         if use_async:
             from tensornvme.async_file_io import AsyncFileWriter
 
-            writer = AsyncFileWriter(open(checkpoint, "wb"), self.N_WRITE_ENTRIES, backend="pthread")
+            writer = AsyncFileWriter(open(checkpoint, "wb", buffering=0), self.N_WRITE_ENTRIES, backend="pthread")
             if id(model) not in self.pinned_state_dicts:
                 self.pinned_state_dicts[id(model)] = create_pinned_state_dict(state_dict)
             self.async_writers.append(writer)
diff --git a/colossalai/checkpoint_io/hybrid_parallel_checkpoint_io.py b/colossalai/checkpoint_io/hybrid_parallel_checkpoint_io.py
index d66171c58..581575058 100644
--- a/colossalai/checkpoint_io/hybrid_parallel_checkpoint_io.py
+++ b/colossalai/checkpoint_io/hybrid_parallel_checkpoint_io.py
@@ -690,7 +690,9 @@ class HybridParallelCheckpointIO(GeneralCheckpointIO):
 
                     from colossalai.utils.safetensors import move_and_save
 
-                    writer = AsyncFileWriter(open(checkpoint, "wb"), self.N_WRITE_ENTRIES, backend="pthread")
+                    writer = AsyncFileWriter(
+                        open(checkpoint, "wb", buffering=0), self.N_WRITE_ENTRIES, backend="pthread"
+                    )
                     if id(model) not in self.pinned_state_dicts:
                         self.pinned_state_dicts[id(model)] = create_pinned_state_dict(state_dict)
                     self.async_writers.append(writer)
diff --git a/colossalai/checkpoint_io/utils.py b/colossalai/checkpoint_io/utils.py
index 09cce3059..eb8bb2dcf 100644
--- a/colossalai/checkpoint_io/utils.py
+++ b/colossalai/checkpoint_io/utils.py
@@ -311,7 +311,7 @@ def async_save_state_dict_shards(
             index_file.append_weight_map(key, shard_file)
         checkpoint_file_path = os.path.join(checkpoint, shard_file)
 
-        writer = AsyncFileWriter(open(checkpoint_file_path, "wb"), n_write_entries, backend="pthread")
+        writer = AsyncFileWriter(open(checkpoint_file_path, "wb", buffering=0), n_write_entries, backend="pthread")
         writers.append(writer)
 
         if pinned_state_dict is not None: