* first copy & past commit from Bert and morgans LSH code

* add easy way to compare to trax original code

* translate most of function

* make trax lsh self attention deterministic with numpy seed + copy paste code

* add same config

* add same config

* make layer init work

* implemented hash_vectors function for lsh attention

* continue reformer translation

* hf LSHSelfAttentionLayer gives same output as trax layer

* refactor code

* refactor code

* refactor code

* refactor

* refactor + add reformer config

* delete bogus file

* split reformer attention layer into two layers

* save intermediate step

* save intermediate step

* make test work

* add complete reformer block layer

* finish reformer layer

* implement causal and self mask

* clean reformer test and refactor code

* fix merge conflicts

* fix merge conflicts

* update init

* fix device for GPU

* fix chunk length init for tests

* include morgans optimization

* improve memory a bit

* improve comment

* factorize num_buckets

* better testing parameters

* make whole model work

* make lm model work

* add t5 copy paste tokenizer

* add chunking feed forward

* clean config

* add improved assert statements

* make tokenizer work

* improve test

* correct typo

* extend config

* add complexer test

* add new axial position embeddings

* add local block attention layer

* clean tests

* refactor

* better testing

* save intermediate progress

* clean test file

* make shorter input length work for model

* allow variable input length

* refactor

* make forward pass for pretrained model work

* add generation possibility

* finish dropout and init

* make style

* refactor

* add first version of RevNet Layers

* make forward pass work and add convert file

* make uploaded model forward pass work

* make uploaded model forward pass work

* refactor code

* add namedtuples and cache buckets

* correct head masks

* refactor

* made reformer more flexible

* make style

* remove set max length

* add attention masks

* fix up tests

* fix lsh attention mask

* make random seed optional for the moment

* improve memory in reformer

* add tests

* make style

* make sure masks work correctly

* detach gradients

* save intermediate

* correct backprob through gather

* make style

* change back num hashes

* rename to labels

* fix rotation shape

* fix detach

* update

* fix trainer

* fix backward dropout

* make reformer more flexible

* fix conflict

* fix

* fix

* add tests for fixed seed in reformer layer

* fix trainer typo

* fix typo in activations

* add fp16 tests

* add fp16 training

* support fp16

* correct gradient bug in reformer

* add fast gelu

* re-add dropout for embedding dropout

* better naming

* better naming

* renaming

* finalize test branch

* finalize tests

* add more tests

* finish tests

* fix

* fix type trainer

* fix fp16 tests

* fix tests

* fix tests

* fix tests

* fix issue with dropout

* fix dropout seeds

* correct random seed on gpu

* finalize random seed for dropout

* finalize random seed for dropout

* remove duplicate line

* correct half precision bug

* make style

* refactor

* refactor

* docstring

* remove sinusoidal position encodings for reformer

* move chunking to modeling_utils

* make style

* clean config

* make style

* fix tests

* fix auto tests

* pretrained models

* fix docstring

* update conversion file

* Update pretrained_models.rst

* fix rst

* fix rst

* update copyright

* fix test path

* fix test path

* fix small issue in test

* include reformer in generation tests

* add docs for axial position encoding

* finish docs

* Update convert_reformer_trax_checkpoint_to_pytorch.py

* remove isort

* include sams comments

* remove wrong comment in utils

* correct typos

* fix typo

* Update reformer.rst

* applied morgans optimization

* make style

* make gpu compatible

* remove bogus file

* big test refactor

* add example for chunking

* fix typo

* add to README
This commit is contained in:
Patrick von Platen
2020-05-07 10:17:01 +02:00
committed by GitHub
parent 877fc56410
commit dca34695d0
19 changed files with 3608 additions and 23 deletions

View File

@@ -13,8 +13,8 @@
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""PyTorch BERT model."""
import inspect
import logging
import os
from typing import Callable, Tuple
@@ -175,7 +175,7 @@ class ModuleUtilsMixin:
extended_attention_mask = (1.0 - extended_attention_mask) * -10000.0
return extended_attention_mask
def get_head_mask(self, head_mask, num_hidden_layers):
def get_head_mask(self, head_mask, num_hidden_layers, is_attention_chunked=False):
"""
# Prepare head mask if needed
# 1.0 in head_mask indicate we keep the head
@@ -189,6 +189,8 @@ class ModuleUtilsMixin:
"""
if head_mask is not None:
head_mask = self._convert_head_mask_to_5d(head_mask, num_hidden_layers)
if is_attention_chunked is True:
head_mask = head_mask.unsqueeze(-1)
else:
head_mask = [None] * num_hidden_layers
@@ -786,6 +788,7 @@ class PreTrainedModel(nn.Module, ModuleUtilsMixin):
attention_mask=None,
decoder_start_token_id=None,
use_cache=None,
**model_specific_kwargs
):
r""" Generates sequences for models with a LM head. The method currently supports greedy decoding, beam-search decoding, sampling with temperature, sampling with top-k or nucleus sampling.
@@ -863,6 +866,9 @@ class PreTrainedModel(nn.Module, ModuleUtilsMixin):
use_cache: (`optional`) bool
If `use_cache` is True, past key values are used to speed up decoding if applicable to model. Defaults to `True`.
model_specific_kwargs: (`optional`) dict
Additional model specific kwargs will be forwarded to the `forward` function of the model.
Return:
output: `torch.LongTensor` of shape `(batch_size * num_return_sequences, sequence_length)`
@@ -1116,6 +1122,7 @@ class PreTrainedModel(nn.Module, ModuleUtilsMixin):
encoder_outputs=encoder_outputs,
attention_mask=attention_mask,
use_cache=use_cache,
model_specific_kwargs=model_specific_kwargs,
)
else:
output = self._generate_no_beam_search(
@@ -1138,6 +1145,7 @@ class PreTrainedModel(nn.Module, ModuleUtilsMixin):
encoder_outputs=encoder_outputs,
attention_mask=attention_mask,
use_cache=use_cache,
model_specific_kwargs=model_specific_kwargs,
)
return output
@@ -1163,6 +1171,7 @@ class PreTrainedModel(nn.Module, ModuleUtilsMixin):
encoder_outputs,
attention_mask,
use_cache,
model_specific_kwargs,
):
""" Generate sequences for each example without beam search (num_beams == 1).
All returned sequence are generated independantly.
@@ -1175,7 +1184,7 @@ class PreTrainedModel(nn.Module, ModuleUtilsMixin):
while cur_len < max_length:
model_inputs = self.prepare_inputs_for_generation(
input_ids, past=past, attention_mask=attention_mask, use_cache=use_cache
input_ids, past=past, attention_mask=attention_mask, use_cache=use_cache, **model_specific_kwargs
)
outputs = self(**model_inputs)
@@ -1288,6 +1297,7 @@ class PreTrainedModel(nn.Module, ModuleUtilsMixin):
encoder_outputs,
attention_mask,
use_cache,
model_specific_kwargs,
):
""" Generate sequences for each example with beam search.
"""
@@ -1314,7 +1324,7 @@ class PreTrainedModel(nn.Module, ModuleUtilsMixin):
while cur_len < max_length:
model_inputs = self.prepare_inputs_for_generation(
input_ids, past=past, attention_mask=attention_mask, use_cache=use_cache
input_ids, past=past, attention_mask=attention_mask, use_cache=use_cache, **model_specific_kwargs
)
outputs = self(**model_inputs) # (batch_size * num_beams, cur_len, vocab_size)
next_token_logits = outputs[0][:, -1, :] # (batch_size * num_beams, vocab_size)
@@ -2087,3 +2097,66 @@ def prune_layer(layer, index, dim=None):
return prune_conv1d_layer(layer, index, dim=1 if dim is None else dim)
else:
raise ValueError("Can't prune layer of class {}".format(layer.__class__))
def apply_chunking_to_forward(
chunk_size: int, chunk_dim: int, forward_fn: Callable[..., torch.Tensor], *input_tensors
) -> torch.Tensor:
"""
This function chunks the `input_tensors` into smaller input tensor parts of size `chunk_size` over the dimension `chunk_dim`.
It then applies a layer `forward_fn` to each chunk independently to save memory.
If the `forward_fn` is independent across the `chunk_dim` this function will yield the
same result as not applying it.
Args:
chunk_size: int - the chunk size of a chunked tensor. `num_chunks` = `len(input_tensors[0]) / chunk_size`
chunk_dim: int - the dimension over which the input_tensors should be chunked
forward_fn: fn - the forward fn of the model
input_tensors: tuple(torch.Tensor) - the input tensors of `forward_fn` which are chunked
Returns:
a Tensor with the same shape the foward_fn would have given if applied
Examples::
# rename the usual forward() fn to forward_chunk()
def forward_chunk(self, hidden_states):
hidden_states = self.decoder(hidden_states)
return hidden_states
# implement a chunked forward function
def forward(self, hidden_states):
return apply_chunking_to_forward(self.chunk_size_lm_head, self.seq_len_dim, self.forward_chunk, hidden_states)
"""
assert len(input_tensors) > 0, "{} has to be a tuple/list of tensors".format(input_tensors)
tensor_shape = input_tensors[0].shape
assert all(
input_tensor.shape == tensor_shape for input_tensor in input_tensors
), "All input tenors have to be of the same shape"
# inspect.signature exist since python 3.5 and is a python method -> no problem with backward compability
num_args_in_forward_chunk_fn = len(inspect.signature(forward_fn).parameters)
assert num_args_in_forward_chunk_fn == len(
input_tensors
), "forward_chunk_fn expects {} arguments, but only {} input tensors are given".format(
num_args_in_forward_chunk_fn, len(input_tensors)
)
if chunk_size > 0:
assert (
input_tensors[0].shape[chunk_dim] % chunk_size == 0
), "The dimension to be chunked {} has to be a multiple of the chunk size {}".format(
input_tensors[0][chunk_dim], chunk_size
)
num_chunks = input_tensors[0].shape[chunk_dim] // chunk_size
# chunk input tensor into tuples
input_tensors_chunks = tuple(input_tensor.chunk(num_chunks, dim=chunk_dim) for input_tensor in input_tensors)
# apply forward fn to every tuple
output_chunks = tuple(forward_fn(*input_tensors_chunk) for input_tensors_chunk in zip(*input_tensors_chunks))
# concatenate output at same dimension
return torch.cat(output_chunks, dim=chunk_dim)
return forward_fn(*input_tensors)