AstrAI/astrai/serialization.py

168 lines
4.8 KiB
Python

import io
import json
import time
from dataclasses import dataclass, field
from pathlib import Path
from typing import Any, Dict, List, Tuple
import safetensors.torch as st
import torch
import torch.distributed as dist
from astrai.parallel.setup import get_rank
_META_FILE = "meta.json"
_CONFIG_FILE = "config.json"
_WEIGHTS_FILE = "model.safetensors"
def save_safetensors(state_dict: dict, path: str | Path) -> None:
st.save_file(state_dict, str(path))
def load_safetensors(path: str | Path) -> dict:
return st.load_file(str(path))
def save_json(data: dict, path: str | Path) -> None:
with open(str(path), "w") as f:
json.dump(data, f, indent=2)
def load_json(path: str | Path) -> dict:
with open(str(path), "r") as f:
return json.load(f)
def save_torch(obj: Any, path: str | Path) -> None:
torch.save(obj, str(path))
def load_torch(path: str | Path, broadcast: bool = False) -> Any:
if not broadcast or not dist.is_initialized():
return torch.load(str(path), map_location="cpu", weights_only=False)
path = Path(path)
rank = get_rank()
if rank == 0:
with open(path, "rb") as f:
raw = f.read()
data_tensor = torch.frombuffer(bytearray(raw), dtype=torch.uint8)
num_bytes = torch.tensor([len(raw)], dtype=torch.long)
else:
num_bytes = torch.tensor([0], dtype=torch.long)
dist.broadcast(num_bytes, src=0)
if rank != 0:
data_tensor = torch.empty(num_bytes.item(), dtype=torch.uint8)
dist.broadcast(data_tensor, src=0)
buf = io.BytesIO(data_tensor.numpy().tobytes())
return torch.load(buf, map_location="cpu", weights_only=False)
def save_model(config: dict, state_dict: dict, save_directory: str) -> None:
save_path = Path(save_directory)
save_path.mkdir(parents=True, exist_ok=True)
save_json(config, save_path / _CONFIG_FILE)
save_safetensors(state_dict, save_path / _WEIGHTS_FILE)
def load_model_config(save_directory: str) -> dict:
return load_json(Path(save_directory) / _CONFIG_FILE)
def load_model_weights(save_directory: str) -> dict:
return load_safetensors(Path(save_directory) / _WEIGHTS_FILE)
def _get_meta(save_path: Path) -> dict:
meta = {}
if get_rank() == 0:
meta = load_json(save_path / _META_FILE)
if dist.is_initialized():
meta_list = [meta]
dist.broadcast_object_list(meta_list, src=0)
meta = meta_list[0]
return meta
def _load_state_dict(save_path: Path, broadcast: bool = False) -> dict:
if not broadcast or not dist.is_initialized():
return load_safetensors(save_path / _WEIGHTS_FILE)
rank = get_rank()
if rank == 0:
state_dict = load_safetensors(save_path / _WEIGHTS_FILE)
specs: List[Tuple[str, List[int], str]] = [
(k, list(state_dict[k].shape), str(state_dict[k].dtype).split(".")[-1])
for k in sorted(state_dict)
]
else:
state_dict = {}
specs = []
specs_list = [specs]
dist.broadcast_object_list(specs_list, src=0)
specs = specs_list[0]
for key, shape, dtype_name in specs:
dtype = getattr(torch, dtype_name)
if rank != 0:
tensor = torch.empty(shape, dtype=dtype, device="cpu")
else:
tensor = state_dict[key].contiguous().cpu()
dist.broadcast(tensor, src=0)
if rank != 0:
state_dict[key] = tensor
return state_dict
@dataclass
class Checkpoint:
state_dict: Dict[str, Any] = field(default_factory=dict)
epoch: int = 0
iteration: int = 0
extra: Dict[str, Any] = field(default_factory=dict)
meta: Dict[str, Any] = field(default_factory=dict)
def save(self, save_dir: str) -> None:
save_path = Path(save_dir)
save_path.mkdir(parents=True, exist_ok=True)
if get_rank() != 0:
return
meta = {
"epoch": self.epoch,
"iteration": self.iteration,
"timestamp": time.strftime("%Y-%m-%dT%H:%M:%S"),
**self.meta,
}
save_json(meta, save_path / _META_FILE)
save_safetensors(self.state_dict, save_path / _WEIGHTS_FILE)
for key, value in self.extra.items():
save_torch(value, save_path / f"{key}.pt")
@classmethod
def load(cls, save_dir: str, broadcast: bool = False) -> "Checkpoint":
save_path = Path(save_dir)
meta = _get_meta(save_path)
state_dict = _load_state_dict(save_path, broadcast=broadcast)
extra = {}
for f in sorted(save_path.iterdir()):
if f.suffix == ".pt":
extra[f.stem] = load_torch(f, broadcast=broadcast)
return cls(
state_dict=state_dict,
epoch=meta.get("epoch", 0),
iteration=meta.get("iteration", 0),
extra=extra,
)