[chore] refactor

colossalai/utils/safetensors.py

@@ -6,6 +6,10 @@ from typing import Dict, List, Tuple
 import torch
 from safetensors.torch import _TYPES
 
+try:
+    from tensornvme.async_file_io import AsyncFileWriter
+except ModuleNotFoundError:
+    raise ModuleNotFoundError("Please install tensornvme to use NVMeOptimizer")
 _TYPES_INV = {v: k for k, v in _TYPES.items()}
 
 
@@ -47,3 +51,14 @@ def prepare(data: Dict[str, torch.Tensor]) -> Tuple[PreparedData, List[torch.Ten
     n = len(metadata_buf)
 
     return PreparedData(n=n, header_bytes=metadata_buf, offset=offset), tensors
+
+
+def save(f_writer: AsyncFileWriter, state_dict: Dict[str, torch.Tensor]) -> None:
+    prepared_data, tensors = prepare(state_dict)
+    n, header_bytes, _ = prepared_data.n, prepared_data.header_bytes, prepared_data.offset
+
+    f_writer.write(n.to_bytes(8, byteorder="little"))
+    f_writer.write(header_bytes)
+
+    for tensor in tensors:
+        f_writer.write_raw(tensor, tensor.data_ptr(), tensor.numel() * tensor.element_size(), f_writer.offset)