Files
AstrAI/astrai/preprocessing/packing.py
T
ViperEkura fec376b0dd fix : 修复策略相关文件的类型注解与抽象方法体
- 修复 strategy.py 单元素 Union 与缺失的参数/返回类型注解
- 修复 train_context.py 8 个 default=None 字段缺 Optional 标记
- 修复 sample.py/packing.py/position_id.py 方法缺参数及返回类型注解
- 修复 factory.py _resolve_type/list_registered 缺类型注解
- 修复 train_config.py 裸 dict/list 缺泛型参数
- abstractmethod body 从 ... 改为 raise NotImplementedError
- feat : checkpoint meta.json 保存 TrainConfig 超参供人工查阅
2026-06-14 16:20:10 +08:00

102 lines
3.1 KiB
Python

"""Sequence packing strategies for shard-level reordering and truncation.
Each strategy receives the accumulated ``{key: [list of token lists]}``
dict for a shard and returns a reordered / truncated version. The
pipeline later flattens the result into contiguous tensors.
"""
from abc import ABC, abstractmethod
from collections import defaultdict
from typing import Dict, List, Tuple
from astrai.factory import BaseFactory
def _truncate(seq: List[int], max_len: int, mode: str) -> List[int]:
if len(seq) <= max_len:
return seq
if mode == "keep_end":
return seq[-max_len:]
return seq[:max_len]
class PackingStrategy(ABC):
"""Reorder and truncate sequences within a shard."""
@abstractmethod
def apply(
self,
keys: Dict[str, List[List[int]]],
max_packed_len: int,
truncation_mode: str,
) -> Dict[str, List[List[int]]]:
raise NotImplementedError
class PackingStrategyFactory(BaseFactory["PackingStrategy"]):
pass
@PackingStrategyFactory.register("simple")
class SimplePacking(PackingStrategy):
def apply(
self,
keys: Dict[str, List[List[int]]],
max_packed_len: int,
truncation_mode: str,
) -> Dict[str, List[List[int]]]:
return {
k: [_truncate(v, max_packed_len, truncation_mode) for v in vals]
for k, vals in keys.items()
}
@PackingStrategyFactory.register("bfd")
class BFDPacking(PackingStrategy):
def apply(
self,
keys: Dict[str, List[List[int]]],
max_packed_len: int,
truncation_mode: str,
) -> Dict[str, List[List[int]]]:
sequences = keys.get("sequence", [])
if not sequences:
return keys
plan = self._plan(sequences, max_packed_len)
reordered: dict = defaultdict(list)
for orig_idx, _ in plan:
for k, vals in keys.items():
reordered[k].append(
_truncate(vals[orig_idx], max_packed_len, truncation_mode)
)
return dict(reordered)
@staticmethod
def _plan(sequences: List[List[int]], max_packed_len: int) -> List[Tuple[int, int]]:
n = len(sequences)
order = sorted(range(n), key=lambda i: len(sequences[i]), reverse=True)
bins: List[List[int]] = []
bin_lengths: List[int] = []
for orig_idx in order:
seq_len = min(len(sequences[orig_idx]), max_packed_len)
best_bin = None
best_remain = max_packed_len + 1
for i, bl in enumerate(bin_lengths):
remain = max_packed_len - bl
if seq_len <= remain < best_remain:
best_remain = remain
best_bin = i
if best_bin is not None:
bins[best_bin].append(orig_idx)
bin_lengths[best_bin] += seq_len
else:
bins.append([orig_idx])
bin_lengths.append(seq_len)
plan: List[Tuple[int, int]] = []
for bin_indices in bins:
for orig_idx in bin_indices:
plan.append((orig_idx, min(len(sequences[orig_idx]), max_packed_len)))
return plan