Add support for IterableDatasets everywhere (#1104)

* Add support for IterableDatasets everywhere

* Added type hints, simplified code and improved coverage in data_loading.py

* Update CHANGELOG.md
This commit is contained in:
Ethan Harris
2020-03-12 12:46:02 -04:00
committed by GitHub
parent 1383f64a5f
commit 2b3f443f6b
7 changed files with 327 additions and 147 deletions
+108 -97
View File
@@ -1,9 +1,11 @@
from abc import ABC, abstractmethod
from typing import Union, List, Tuple, Callable
import torch.distributed as dist
from torch.utils.data import SequentialSampler, DataLoader
from torch.utils.data.distributed import DistributedSampler
from pytorch_lightning.core import LightningModule
from pytorch_lightning.utilities.debugging import MisconfigurationException
try:
@@ -23,6 +25,15 @@ else:
XLA_AVAILABLE = True
def _has_len(dataloader: DataLoader) -> bool:
try:
# try getting the length
_ = len(dataloader)
return True
except TypeError:
return False
class TrainerDataLoadingMixin(ABC):
# this is just a summary on variables used in this abstract class,
@@ -35,27 +46,30 @@ class TrainerDataLoadingMixin(ABC):
use_tpu: bool
tpu_local_core_rank: int
train_dataloader: DataLoader
num_training_batches: int
num_training_batches: Union[int, float]
val_check_batch: ...
val_dataloaders: DataLoader
num_val_batches: int
test_dataloaders: DataLoader
num_test_batches: int
val_dataloaders: List[DataLoader]
num_val_batches: Union[int, float]
test_dataloaders: List[DataLoader]
num_test_batches: Union[int, float]
train_percent_check: float
val_percent_check: float
test_percent_check: float
@abstractmethod
def is_overriden(self, *args):
"""Warning: this is just empty shell for code implemented in other class."""
def _percent_range_check(self, name):
def _percent_range_check(self, name: str) -> None:
value = getattr(self, name)
msg = f"`{name}` must lie in the range [0.0, 1.0], but got {value:.3f}."
if name == "val_check_interval":
msg += " If you want to disable validation set `val_percent_check` to 0.0 instead."
msg = f'`{name}` must lie in the range [0.0, 1.0], but got {value:.3f}.'
if name == 'val_check_interval':
msg += ' If you want to disable validation set `val_percent_check` to 0.0 instead.'
if not 0. <= value <= 1.:
raise ValueError(msg)
def auto_add_sampler(self, dataloader, train):
def auto_add_sampler(self, dataloader: DataLoader, train: bool) -> DataLoader:
if self.use_ddp or self.use_ddp2 or self.use_tpu:
dl_args = {
'dataset': dataloader.dataset,
@@ -88,14 +102,14 @@ class TrainerDataLoadingMixin(ABC):
dataloader = DataLoader(**dl_args)
return dataloader
def reset_train_dataloader(self, model):
"""
Dataloaders are provided by the model
:param model:
:return:
"""
def reset_train_dataloader(self, model: LightningModule) -> None:
"""Resets the train dataloader and initialises required variables
(number of batches, when to validate, etc.).
self.train_dataloader = self.request_data_loader(model.train_dataloader)
Args:
model: The current `LightningModule`
"""
self.train_dataloader = self.request_dataloader(model.train_dataloader)
self.num_training_batches = 0
# automatically add samplers
@@ -103,7 +117,7 @@ class TrainerDataLoadingMixin(ABC):
self._percent_range_check('train_percent_check')
if self.is_infinite_dataloader(self.train_dataloader):
if not _has_len(self.train_dataloader):
self.num_training_batches = float('inf')
else:
# try getting the length
@@ -117,122 +131,119 @@ class TrainerDataLoadingMixin(ABC):
self.val_check_batch = self.val_check_interval
if self.val_check_batch > self.num_training_batches:
raise ValueError(
f"`val_check_interval` ({self.val_check_interval}) must be less than or equal "
f"to the number of the training batches ({self.num_training_batches}). "
f"If you want to disable validation set `val_percent_check` to 0.0 instead.")
f'`val_check_interval` ({self.val_check_interval}) must be less than or equal '
f'to the number of the training batches ({self.num_training_batches}). '
'If you want to disable validation set `val_percent_check` to 0.0 instead.')
else:
if self.is_infinite_dataloader(self.train_dataloader):
m = '''
When using an infinite DataLoader (e.g. with an IterableDataset or when DataLoader
does not implement `__len__`) for `train_dataloader`, `Trainer(val_check_interval)`
must be an int. An int k specifies checking validation every k training batches.
'''
raise MisconfigurationException(m)
if not _has_len(self.train_dataloader):
raise MisconfigurationException(
'When using an infinite DataLoader (e.g. with an IterableDataset or when '
'DataLoader does not implement `__len__`) for `train_dataloader`, '
'`Trainer(val_check_interval)` must be an int. An int k specifies checking '
'validation every k training batches.')
self._percent_range_check('val_check_interval')
self.val_check_batch = int(self.num_training_batches * self.val_check_interval)
self.val_check_batch = max(1, self.val_check_batch)
def is_infinite_dataloader(self, dataloader):
try:
# try getting the length
_ = len(dataloader)
return False
except TypeError as e:
return True
def _reset_eval_dataloader(self, model: LightningModule,
mode: str) -> Tuple[int, List[DataLoader]]:
"""Generic method to reset a dataloader for evaluation.
def reset_val_dataloader(self, model):
"""
Dataloaders are provided by the model
:param model:
:return:
"""
if not self.is_overriden('validation_step'):
return
Args:
model: The current `LightningModule`
mode: Either `'val'` or `'test'`
self.val_dataloaders = self.request_data_loader(model.val_dataloader)
if not isinstance(self.val_dataloaders, list):
self.val_dataloaders = [self.val_dataloaders]
self.num_val_batches = 0
Returns:
Tuple (num_batches, dataloaders)
"""
dataloaders = self.request_dataloader(getattr(model, f'{mode}_dataloader'))
if not isinstance(dataloaders, list):
dataloaders = [dataloaders]
# add samplers
self.val_dataloaders = [self.auto_add_sampler(dl, train=False)
for dl in self.val_dataloaders if dl]
dataloaders = [self.auto_add_sampler(dl, train=False) for dl in dataloaders if dl]
# determine number of validation batches
# val datasets could be none, 1 or 2+
if self.val_dataloaders is not None:
self._percent_range_check('val_percent_check')
num_batches = 0
self.num_val_batches = sum(len(dataloader) for dataloader in self.val_dataloaders)
self.num_val_batches = int(self.num_val_batches * self.val_percent_check)
# determine number of batches
# datasets could be none, 1 or 2+
if len(dataloaders) != 0:
for dataloader in dataloaders:
if not _has_len(dataloader):
num_batches = float('inf')
break
def reset_test_dataloader(self, model):
"""Dataloaders are provided by the model.
percent_check = getattr(self, f'{mode}_percent_check')
:param model:
if num_batches != float('inf'):
self._percent_range_check(f'{mode}_percent_check')
num_batches = sum(len(dataloader) for dataloader in dataloaders)
num_batches = int(num_batches * percent_check)
elif percent_check not in (0.0, 1.0):
raise MisconfigurationException(
'When using an infinite DataLoader (e.g. with an IterableDataset or when '
f'DataLoader does not implement `__len__`) for `{mode}_dataloader`, '
f'`Trainer({mode}_percent_check)` must be `0.0` or `1.0`.')
return num_batches, dataloaders
def reset_val_dataloader(self, model: LightningModule) -> None:
"""Resets the validation dataloader and determines the number of batches.
Args:
model: The current `LightningModule`
"""
if not self.is_overriden('test_step'):
return
if self.is_overriden('validation_step'):
self.num_val_batches, self.val_dataloaders =\
self._reset_eval_dataloader(model, 'val')
# get actual loader
self.test_dataloaders = self.request_data_loader(model.test_dataloader)
if not isinstance(self.test_dataloaders, list):
self.test_dataloaders = [self.test_dataloaders]
self.num_test_batches = 0
def reset_test_dataloader(self, model) -> None:
"""Resets the validation dataloader and determines the number of batches.
# add samplers
self.test_dataloaders = [self.auto_add_sampler(dl, train=False)
for dl in self.test_dataloaders if dl]
# determine number of test batches
if self.test_dataloaders is not None:
self._percent_range_check('test_percent_check')
len_sum = sum(len(dataloader) for dataloader in self.test_dataloaders)
self.num_test_batches = len_sum
self.num_test_batches = int(self.num_test_batches * self.test_percent_check)
def request_data_loader(self, data_loader_fx):
Args:
model: The current `LightningModule`
"""
Handles downloading data in the GPU or TPU case.
if self.is_overriden('test_step'):
self.num_test_batches, self.test_dataloaders =\
self._reset_eval_dataloader(model, 'test')
:param data_loader_fx:
:return:
def request_dataloader(self, dataloader_fx: Callable) -> DataLoader:
"""Handles downloading data in the GPU or TPU case.
Args:
dataloader_fx: The bound dataloader getter
Returns:
The dataloader
"""
dataloader = dataloader_fx()
# get the function we'll use to get data
if self.use_ddp or self.use_ddp2:
data_loader = data_loader_fx()
# all processes wait until data download has happened
dist.barrier()
# data download/load on TPU
elif self.use_tpu and XLA_AVAILABLE:
data_loader = data_loader_fx()
# all processes wait until data download has happened
torch_xla.core.xla_model.rendezvous("pl.TrainerDataLoadingMixin.get_dataloaders")
torch_xla.core.xla_model.rendezvous('pl.TrainerDataLoadingMixin.get_dataloaders')
# regular start
else:
data_loader = data_loader_fx()
return dataloader
return data_loader
def determine_data_use_amount(self, train_percent_check, val_percent_check,
test_percent_check, overfit_pct):
"""
Use less data for debugging purposes
def determine_data_use_amount(self, train_percent_check: float, val_percent_check: float,
test_percent_check: float, overfit_pct: float) -> None:
"""Use less data for debugging purposes
"""
self.train_percent_check = train_percent_check
self.val_percent_check = val_percent_check
self.test_percent_check = test_percent_check
if overfit_pct > 0:
if overfit_pct > 1:
raise ValueError(f"`overfit_pct` must be not greater than 1.0, but got "
f"{overfit_pct:.3f}.")
raise ValueError(
f'`overfit_pct` must be not greater than 1.0, but got {overfit_pct:.3f}.')
self.train_percent_check = overfit_pct
self.val_percent_check = overfit_pct