Files
AstrAI/astrai/serialization/dataset.py
T
ViperEkura 115192c67c refactor: remove H5 storage backend in favor of mmap bin
- Remove H5Store, H5Writer, save_h5/load_h5 and h5py dependency
- MmapStore (bin) is the sole pre-tokenized storage backend
- Move setup_logging after imports to fix E402 in __init__.py
- Clean up unused imports across test files
- Move inline test imports to file top
2026-07-29 12:50:27 +08:00

83 lines
2.8 KiB
Python

"""Dataset storage serialization helpers (memory-mapped binary)."""
import json
import os
from typing import Any, Dict, List, Optional
import numpy as np
import torch
from torch import Tensor
def save_bin(
file_path: str,
tensor_group: Dict[str, List[Tensor]],
record_keys: Optional[List[str]] = None,
):
"""Save tensors as memory-mapped binary files.
When *record_keys* is provided, those keys are written with per-record
cumulative offsets in ``meta.json`` so that ``MmapStore.fetch_record``
can slice individual records from the concatenated binary without
cross-record concatenation. Keys not in *record_keys* (e.g. SEQ
``sequence``) are written as a single contiguous stream without
offsets, preserving backward compatibility.
Nested keys (``List[List[Tensor]]`` such as GRPO ``responses``) are
not supported in bin format — use JSONL for those.
"""
os.makedirs(file_path, exist_ok=True)
record_keys = set(record_keys or [])
meta = {}
for key, tensors in tensor_group.items():
if tensors and isinstance(tensors[0], list):
raise ValueError(
f"Nested key '{key}' (List[List[Tensor]]) is not supported "
f"in bin format. Use JSONL storage instead."
)
cat = torch.cat(tensors, dim=0)
entry: Dict[str, Any] = {
"shape": list(cat.shape),
"dtype": str(cat.dtype).split(".")[-1],
}
if key in record_keys:
offsets = [0]
for t in tensors:
offsets.append(offsets[-1] + t.shape[0])
entry["offsets"] = offsets
meta[key] = entry
np.asarray(cat.cpu().numpy()).tofile(os.path.join(file_path, f"{key}.bin"))
with open(os.path.join(file_path, "meta.json"), "w") as f:
json.dump(meta, f)
def load_bin(file_path: str) -> Dict[str, List[Tensor]]:
with open(os.path.join(file_path, "meta.json"), "r") as f:
meta = json.load(f)
segments: Dict[str, List[Tensor]] = {}
for key, info in meta.items():
arr = np.memmap(
os.path.join(file_path, f"{key}.bin"),
dtype=info["dtype"],
mode="c",
shape=tuple(info["shape"]),
)
segments[key] = [torch.from_numpy(arr)]
return segments
def load_bin_offsets(file_path: str) -> Dict[str, List[int]]:
"""Read per-record cumulative offsets from ``meta.json``.
Returns an empty dict when no key has offsets (legacy bin files),
in which case record-mode access falls back to per-record segment
indexing (JSONL layout).
"""
with open(os.path.join(file_path, "meta.json"), "r") as f:
meta = json.load(f)
offsets: Dict[str, List[int]] = {}
for key, info in meta.items():
if "offsets" in info:
offsets[key] = info["offsets"]
return offsets