# coding=utf-8
# Copyright (c) Facebook, Inc. and its affiliates.
#
# This source code is licensed under the MIT license found in the
# LICENSE file in the root directory of this source tree.
# copied from fairseq/fairseq/data/indexed_dataset.py
# Removed IndexedRawTextDataset since it relied on Fairseq dictionary
# other slight modifications to remove fairseq dependencies
# Added document index to index file and made it accessible.
# An empty sentence no longer separates documents.
import logging
import os
import shutil
import struct
import time
from functools import lru_cache
from itertools import accumulate
import numpy as np
import oneflow as flow
logger = logging.getLogger(__name__)
def __best_fitting_dtype(vocab_size=None):
if vocab_size is not None and vocab_size < 65500:
return np.uint16
else:
return np.int32
def get_available_dataset_impl():
return ["lazy", "cached", "mmap"]
def infer_dataset_impl(path):
if IndexedDataset.exists(path):
with open(index_file_path(path), "rb") as f:
magic = f.read(8)
if magic == IndexedDataset._HDR_MAGIC:
return "cached"
elif magic == MMapIndexedDataset.Index._HDR_MAGIC[:8]:
return "mmap"
else:
return None
else:
logger.info(f"Dataset does not exist: {path}")
logger.info(
"Path should be a basename that both .idx and .bin can be "
"appended to get full filenames."
)
return None
def make_builder(out_file, impl, vocab_size=None):
if impl == "mmap":
return MMapIndexedDatasetBuilder(out_file, dtype=__best_fitting_dtype(vocab_size))
else:
return IndexedDatasetBuilder(out_file)
def make_dataset(path, impl, skip_warmup=False):
if not IndexedDataset.exists(path):
logger.info(f"Dataset does not exist: {path}")
logger.info(
"Path should be a basename that both .idx and .bin can be "
"appended to get full filenames."
)
raise ValueError(f"Dataset does not exist: {path}")
if impl == "infer":
impl = infer_dataset_impl(path)
if impl == "lazy" and IndexedDataset.exists(path):
return IndexedDataset(path)
elif impl == "cached" and IndexedDataset.exists(path):
return IndexedCachedDataset(path)
elif impl == "mmap" and MMapIndexedDataset.exists(path):
return MMapIndexedDataset(path, skip_warmup)
logger.info(f"Unknown dataset implementation: {impl}")
return None
def dataset_exists(path, impl):
if impl == "mmap":
return MMapIndexedDataset.exists(path)
else:
return IndexedDataset.exists(path)
def read_longs(f, n):
a = np.empty(n, dtype=np.int64)
f.readinto(a)
return a
def write_longs(f, a):
f.write(np.array(a, dtype=np.int64))
dtypes = {
1: np.uint8,
2: np.int8,
3: np.int16,
4: np.int32,
5: np.int64,
6: np.float32,
7: np.double,
8: np.uint16,
}
def code(dtype):
for k in dtypes.keys():
if dtypes[k] == dtype:
return k
raise ValueError(dtype)
def index_file_path(prefix_path):
return prefix_path + ".idx"
def data_file_path(prefix_path):
return prefix_path + ".bin"
def create_doc_idx(sizes):
doc_idx = [0]
for i, s in enumerate(sizes):
if s == 0:
doc_idx.append(i + 1)
return doc_idx
[docs]class IndexedDataset(flow.utils.data.Dataset):
"""Loader for IndexedDataset"""
_HDR_MAGIC = b"TNTIDX\x00\x00"
def __init__(self, path):
super().__init__()
self.path = path
self.data_file = None
self.read_index(path)
def read_index(self, path):
with open(index_file_path(path), "rb") as f:
magic = f.read(8)
assert magic == self._HDR_MAGIC, (
"Index file doesn't match expected format. "
"Make sure that --dataset-impl is configured properly."
)
version = f.read(8)
assert struct.unpack("<Q", version) == (1,)
code, self.element_size = struct.unpack("<QQ", f.read(16))
self.dtype = dtypes[code]
self._len, self.s = struct.unpack("<QQ", f.read(16))
self.doc_count = struct.unpack("<Q", f.read(8))
self.dim_offsets = read_longs(f, self._len + 1)
self.data_offsets = read_longs(f, self._len + 1)
self.sizes = read_longs(f, self.s)
self.doc_idx = read_longs(f, self.doc_count)
def read_data(self, path):
self.data_file = open(data_file_path(path), "rb", buffering=0)
def check_index(self, i):
if i < 0 or i >= self._len:
raise IndexError("index out of range")
def __del__(self):
if self.data_file:
self.data_file.close()
# @lru_cache(maxsize=8)
def __getitem__(self, idx):
if not self.data_file:
self.read_data(self.path)
if isinstance(idx, int):
i = idx
self.check_index(i)
tensor_size = self.sizes[self.dim_offsets[i] : self.dim_offsets[i + 1]]
a = np.empty(tensor_size, dtype=self.dtype)
self.data_file.seek(self.data_offsets[i] * self.element_size)
self.data_file.readinto(a)
return a
elif isinstance(idx, slice):
start, stop, step = idx.indices(len(self))
if step != 1:
raise ValueError("Slices into indexed_dataset must be contiguous")
sizes = self.sizes[self.dim_offsets[start] : self.dim_offsets[stop]]
size = sum(sizes)
a = np.empty(size, dtype=self.dtype)
self.data_file.seek(self.data_offsets[start] * self.element_size)
self.data_file.readinto(a)
offsets = list(accumulate(sizes))
sents = np.split(a, offsets[:-1])
return sents
def __len__(self):
return self._len
def num_tokens(self, index):
return self.sizes[index]
def size(self, index):
return self.sizes[index]
@staticmethod
def exists(path):
return os.path.exists(index_file_path(path)) and os.path.exists(data_file_path(path))
@property
def supports_prefetch(self):
return False # avoid prefetching to save memory
[docs]class IndexedCachedDataset(IndexedDataset):
def __init__(self, path):
super().__init__(path)
self.cache = None
self.cache_index = {}
@property
def supports_prefetch(self):
return True
def prefetch(self, indices):
if all(i in self.cache_index for i in indices):
return
if not self.data_file:
self.read_data(self.path)
indices = sorted(set(indices))
total_size = 0
for i in indices:
total_size += self.data_offsets[i + 1] - self.data_offsets[i]
self.cache = np.empty(total_size, dtype=self.dtype)
ptx = 0
self.cache_index.clear()
for i in indices:
self.cache_index[i] = ptx
size = self.data_offsets[i + 1] - self.data_offsets[i]
a = self.cache[ptx : ptx + size]
self.data_file.seek(self.data_offsets[i] * self.element_size)
self.data_file.readinto(a)
ptx += size
if self.data_file:
# close and delete data file after prefetch so we can pickle
self.data_file.close()
self.data_file = None
# @lru_cache(maxsize=8)
def __getitem__(self, idx):
if isinstance(idx, int):
i = idx
self.check_index(i)
tensor_size = self.sizes[self.dim_offsets[i] : self.dim_offsets[i + 1]]
a = np.empty(tensor_size, dtype=self.dtype)
ptx = self.cache_index[i]
np.copyto(a, self.cache[ptx : ptx + a.size])
return a
elif isinstance(idx, slice):
# Hack just to make this work, can optimizer later if necessary
sents = []
for i in range(*idx.indices(len(self))):
sents.append(self[i])
return sents
class IndexedDatasetBuilder(object):
element_sizes = {
np.uint8: 1,
np.int8: 1,
np.int16: 2,
np.int32: 4,
np.int64: 8,
np.float32: 4,
np.double: 8,
}
def __init__(self, out_file, dtype=np.int32):
self.out_file = open(out_file, "wb")
self.dtype = dtype
self.data_offsets = [0]
self.dim_offsets = [0]
self.sizes = []
self.element_size = self.element_sizes[self.dtype]
self.doc_idx = [0]
def add_item(self, tensor):
bytes = self.out_file.write(np.array(tensor.numpy(), dtype=self.dtype))
self.data_offsets.append(self.data_offsets[-1] + bytes / self.element_size)
for s in tensor.size():
self.sizes.append(s)
self.dim_offsets.append(self.dim_offsets[-1] + len(tensor.size()))
def end_document(self):
self.doc_idx.append(len(self.sizes))
def merge_file_(self, another_file):
index = IndexedDataset(another_file)
assert index.dtype == self.dtype
begin = self.data_offsets[-1]
for offset in index.data_offsets[1:]:
self.data_offsets.append(begin + offset)
self.sizes.extend(index.sizes)
begin = self.dim_offsets[-1]
for dim_offset in index.dim_offsets[1:]:
self.dim_offsets.append(begin + dim_offset)
with open(data_file_path(another_file), "rb") as f:
while True:
data = f.read(1024)
if data:
self.out_file.write(data)
else:
break
def finalize(self, index_file):
self.out_file.close()
index = open(index_file, "wb")
index.write(b"TNTIDX\x00\x00")
index.write(struct.pack("<Q", 1))
index.write(struct.pack("<QQ", code(self.dtype), self.element_size))
index.write(struct.pack("<QQ", len(self.data_offsets) - 1, len(self.sizes)))
index.write(struct.pack("<Q", len(self.doc_idx)))
write_longs(index, self.dim_offsets)
write_longs(index, self.data_offsets)
write_longs(index, self.sizes)
write_longs(index, self.doc_idx)
index.close()
def _warmup_mmap_file(path):
with open(path, "rb") as stream:
while stream.read(100 * 1024 * 1024):
pass
[docs]class MMapIndexedDataset(flow.utils.data.Dataset):
class Index(object):
_HDR_MAGIC = b"MMIDIDX\x00\x00"
@classmethod
def writer(cls, path, dtype):
class _Writer(object):
def __enter__(self):
self._file = open(path, "wb")
self._file.write(cls._HDR_MAGIC)
self._file.write(struct.pack("<Q", 1))
self._file.write(struct.pack("<B", code(dtype)))
return self
@staticmethod
def _get_pointers(sizes):
dtype_size = dtype().itemsize
address = 0
pointers = []
for size in sizes:
pointers.append(address)
address += size * dtype_size
return pointers
def write(self, sizes, doc_idx):
pointers = self._get_pointers(sizes)
self._file.write(struct.pack("<Q", len(sizes)))
self._file.write(struct.pack("<Q", len(doc_idx)))
sizes = np.array(sizes, dtype=np.int32)
self._file.write(sizes.tobytes(order="C"))
del sizes
pointers = np.array(pointers, dtype=np.int64)
self._file.write(pointers.tobytes(order="C"))
del pointers
doc_idx = np.array(doc_idx, dtype=np.int64)
self._file.write(doc_idx.tobytes(order="C"))
def __exit__(self, exc_type, exc_val, exc_tb):
self._file.close()
return _Writer()
def __init__(self, path, skip_warmup=False):
with open(path, "rb") as stream:
magic_test = stream.read(9)
assert self._HDR_MAGIC == magic_test, (
"Index file doesn't match expected format. "
"Make sure that --dataset-impl is configured properly."
)
version = struct.unpack("<Q", stream.read(8))
assert (1,) == version
(dtype_code,) = struct.unpack("<B", stream.read(1))
self._dtype = dtypes[dtype_code]
self._dtype_size = self._dtype().itemsize
self._len = struct.unpack("<Q", stream.read(8))[0]
self._doc_count = struct.unpack("<Q", stream.read(8))[0]
offset = stream.tell()
if not skip_warmup:
logger.info("warming up index mmap file...")
_warmup_mmap_file(path)
self._bin_buffer_mmap = np.memmap(path, mode="r", order="C")
self._bin_buffer = memoryview(self._bin_buffer_mmap)
logger.info("reading sizes...")
self._sizes = np.frombuffer(
self._bin_buffer, dtype=np.int32, count=self._len, offset=offset
)
logger.info("reading pointers...")
self._pointers = np.frombuffer(
self._bin_buffer,
dtype=np.int64,
count=self._len,
offset=offset + self._sizes.nbytes,
)
logger.info("reading document index...")
self._doc_idx = np.frombuffer(
self._bin_buffer,
dtype=np.int64,
count=self._doc_count,
offset=offset + self._sizes.nbytes + self._pointers.nbytes,
)
def __del__(self):
self._bin_buffer_mmap._mmap.close()
del self._bin_buffer_mmap
@property
def dtype(self):
return self._dtype
@property
def sizes(self):
return self._sizes
@property
def doc_idx(self):
return self._doc_idx
@lru_cache(maxsize=8)
def __getitem__(self, i):
return self._pointers[i], self._sizes[i]
def __len__(self):
return self._len
def __init__(self, path, skip_warmup=False):
super().__init__()
self._path = None
self._index = None
self._bin_buffer = None
self._do_init(path, skip_warmup)
def __getstate__(self):
return self._path
def __setstate__(self, state):
self._do_init(state)
def _do_init(self, path, skip_warmup):
self._path = path
self._index = self.Index(index_file_path(self._path), skip_warmup)
if not skip_warmup:
logger.info("warming up data mmap file...")
_warmup_mmap_file(data_file_path(self._path))
logger.info("creating numpy buffer of mmap...")
self._bin_buffer_mmap = np.memmap(data_file_path(self._path), mode="r", order="C")
logger.info("creating memory view of numpy buffer...")
self._bin_buffer = memoryview(self._bin_buffer_mmap)
def __del__(self):
self._bin_buffer_mmap._mmap.close()
del self._bin_buffer_mmap
del self._index
def __len__(self):
return len(self._index)
# @lru_cache(maxsize=8)
def __getitem__(self, idx):
if isinstance(idx, int):
ptr, size = self._index[idx]
np_array = np.frombuffer(
self._bin_buffer, dtype=self._index.dtype, count=size, offset=ptr
)
return np_array
elif isinstance(idx, slice):
start, stop, step = idx.indices(len(self))
if step != 1:
raise ValueError("Slices into indexed_dataset must be contiguous")
ptr = self._index._pointers[start]
sizes = self._index._sizes[idx]
offsets = list(accumulate(sizes))
total_size = sum(sizes)
np_array = np.frombuffer(
self._bin_buffer, dtype=self._index.dtype, count=total_size, offset=ptr
)
sents = np.split(np_array, offsets[:-1])
return sents
[docs] def get(self, idx, offset=0, length=None):
"""Retrieves a single item from the dataset with the option to only
return a portion of the item.
get(idx) is the same as [idx] but get() does not support slicing.
"""
ptr, size = self._index[idx]
if length is None:
length = size - offset
ptr += offset * np.dtype(self._index.dtype).itemsize
np_array = np.frombuffer(
self._bin_buffer, dtype=self._index.dtype, count=length, offset=ptr
)
return np_array
@property
def sizes(self):
return self._index.sizes
@property
def doc_idx(self):
return self._index.doc_idx
def get_doc_idx(self):
return self._index._doc_idx
def set_doc_idx(self, doc_idx_):
self._index._doc_idx = doc_idx_
@property
def supports_prefetch(self):
return False
@staticmethod
def exists(path):
return os.path.exists(index_file_path(path)) and os.path.exists(data_file_path(path))
class MMapIndexedDatasetBuilder(object):
def __init__(self, out_file, dtype=np.int64):
self._data_file = open(out_file, "wb")
self._dtype = dtype
self._sizes = []
self._doc_idx = [0]
def add_item(self, tensor):
np_array = np.array(tensor.numpy(), dtype=self._dtype)
self._data_file.write(np_array.tobytes(order="C"))
self._sizes.append(np_array.size)
def end_document(self):
self._doc_idx.append(len(self._sizes))
def merge_file_(self, another_file):
# Concatenate index
index = MMapIndexedDataset.Index(index_file_path(another_file))
assert index.dtype == self._dtype
for size in index.sizes:
self._sizes.append(size)
# Concatenate data
with open(data_file_path(another_file), "rb") as f:
shutil.copyfileobj(f, self._data_file)
def finalize(self, index_file):
self._data_file.close()
with MMapIndexedDataset.Index.writer(index_file, self._dtype) as index:
index.write(self._sizes, self._doc_idx)
def get_indexed_dataset(data_prefix, data_impl, skip_warmup):
logger.info("building dataset index ...")
start_time = time.time()
indexed_dataset = make_dataset(data_prefix, data_impl, skip_warmup)
assert indexed_dataset.sizes.shape[0] == indexed_dataset.doc_idx[-1]
logger.info(
"Finished creating indexed dataset in {:4f} " "seconds".format(time.time() - start_time)
)
logger.info("indexed dataset stats:")
logger.info("number of documents: {}".format(indexed_dataset.doc_idx.shape[0] - 1))
logger.info("number of sentences: {}".format(indexed_dataset.sizes.shape[0]))
return indexed_dataset