# Copyright (c) 2021 Graphcore Ltd. All rights reserved. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # 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. # Read wikipedia datafiles and see that they conform to the schema # Schema: # input_ids: tokens after masking # attention_mask: 0 if is a padding token, 1 otherwise # token_type_ids: sentence 0/1 # labels: 0 if corresponding token not masked, original value otherwise # nsp: 1 if is next sentence, 0 otherwise # # Here is an example data point: # # input_ids - the encoded tokens after mlm maskng and padding # tensor([ 101, 1996, 2536, 103, 21670, 1998, 2385, 3461, 8333, 2915, # 2011, 1996, 3626, 1997, 9348, 2620, 2020, 103, 1998, 2207, # 103, 9274, 1999, 1996, 3440, 4516, 1000, 103, 23736, 12879, # 1024, 9348, 2620, 1000, 1010, 103, 2011, 17754, 10635, 1012, # 102, 103, 2804, 1010, 103, 3152, 2207, 1010, 1999, 2494, # 1010, 1037, 2093, 1011, 5860, 103, 2275, 4820, 2035, 1997, # 9274, 1005, 1055, 2694, 103, 2385, 2050, 103, 2143, 8333, # 3141, 103, 1996, 3260, 1010, 2164, 2035, 2694, 21670, 2013, # 2686, 1010, 2731, 1998, 4888, 103, 1010, 1998, 4367, 4620, # 2579, 1999, 3462, 1012, 102, 0, 0, 0, 0, 0, # 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, # 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, # 0, 0, 0, 0, 0, 0, 0, 0]) # # attention_mask - 1 is valid input, 0 is padding. # tensor([1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, # 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, # 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, # 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, # 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, # 0, 0, 0, 0, 0, 0, 0, 0]) # # Type IDs. First 0s are first sentence. Then the 1s are the second sentence. The remaining 0s are padding. # tensor([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, # 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, # 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, # 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, # 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, # 0, 0, 0, 0, 0, 0, 0, 0]) # # Mask LM positions # tensor([ 3, 17, 20, 27, 35, 41, 44, 55, 64, 67, 71, 78, 85, 93, 0, 0, 0, 0, # 0, 0]) # # Mask LM Labels: Ground truth of the mlm masked tokens. # 0 is not Masked. Any other value is the ground truth token before masking. # tensor([ 2547, 9227, 2011, 2139, 4354, 1999, 12076, 4966, 1998, 3461, # 2000, 21670, 8333, 1012, 0, 0, 0, 0, 0, 0]) # NSP. 1 means the two sentences came after each other in the original text. # 0 means they didn't # tensor([0]) import numpy as np from collections import Counter from tqdm import tqdm from args import parse_bert_args from pretraining_data import get_dataloader from ipu_options import get_options import transformers import pytest def check_dimensions(config, tokens, attn_mask, token_types, mask_lm_positions, labels, nsp): assert tokens.shape == (config.sequence_length,) assert attn_mask.shape == (config.sequence_length,) assert token_types.shape == (config.sequence_length,) assert mask_lm_positions.shape == (config.mask_tokens,) assert labels.shape == (config.mask_tokens,) assert nsp.shape == (1,) def check_tokens(config, tokens, mask_lm_position, labels): """ First sentence starts with 101 ([CLS]) Second sentence starts and ends with 102 ([SEP]) Padding at end of sequence is 0s, this won't be masked. Mask token is 101 ([MASK]) """ # Remove masked tokens for tests tokens_nomask = np.delete(tokens, mask_lm_position[labels != 0]) assert tokens_nomask[0] == 101 # sequence starts with [CLS] # Only 1 [CLS] assert tokens_nomask[tokens_nomask == 101].shape[0] == 1 # Sentence 1 and 2 finish by [SEP] assert tokens_nomask[tokens_nomask == 102].shape[0] == 2 # After second 102 [SEP] it should be all padding indices_102 = np.where(tokens_nomask == 102)[0] assert np.all(tokens_nomask[indices_102[1] + 1 :] == 0) # The unmasked tokens in the sentences minus special characters # have values between 999 and vocab_size slice_0 = slice(1, indices_102[0]) slice_1 = slice(indices_102[0] + 1, indices_102[1]) sentence_0 = tokens_nomask[slice_0] sentence_1 = tokens_nomask[slice_1] special_tokens = np.array([100, 101, 102, 103, 0]) normal_tokens_0 = sentence_0[~np.in1d(sentence_0, special_tokens)] normal_tokens_1 = sentence_1[~np.in1d(sentence_1, special_tokens)] assert np.all((normal_tokens_0 >= 999) & (normal_tokens_0 < config.vocab_size)) assert np.all((normal_tokens_1 >= 999) & (normal_tokens_1 < config.vocab_size)) def check_attention_mask(attn_mask, tokens): """ Starts with sequence of 1s. If padded will continue with sequence of 0s """ # Can only be 0 or 1 assert np.all((attn_mask == 0) | (attn_mask == 1)) idx_zeros = np.where(attn_mask == 0)[0] if idx_zeros.size > 0: idx = idx_zeros[0] assert np.all(attn_mask[:idx] == 1) assert np.all(attn_mask[idx:] == 0) # Check that the token padding (0) matches attn_mask assert tokens[idx - 1] == 102 assert np.all(tokens[idx:] == 0) else: assert np.all(attn_mask[:] == 1) def check_token_type(token_types): """ This is a mask for the two different sentences plus padding Sentence 0: 0,0,0,0,0 Sentence 1: 1,1,1,1,1,1,1 Padding: 0,0,0,0,0,0 """ # Can only be 0 or 1 assert np.all((token_types == 0) | (token_types == 1)) # Find sentence boundary idx_ones = np.where(token_types == 1)[0] # Should be two sentences assert idx_ones.size > 0 idx = idx_ones[0] assert np.all(token_types[:idx] == 0) idx_zeros = np.where(token_types[idx:] == 0)[0] if idx_zeros.size > 0: # There is padding idx_pad = idx_zeros[0] + idx assert np.all(token_types[idx:idx_pad] == 1) assert np.all(token_types[idx_pad:] == 0) else: assert np.all(token_types[idx:] == 1) def check_mask_lm_positions(config, mask_lm_positions): """ Position of MLM tokens. Must be less then the sequence_length of tokens. """ assert np.all(mask_lm_positions < config.sequence_length) def check_labels(config, tokens, mask_lm_positions, labels): """ MLM Labels value should be 0, 103, or in [0, vocab_size)? 80% it will be 103 10% it will be the same 10% it will be random int between [0, vocab_size) """ masked_tokens = tokens[mask_lm_positions[labels != 0]] assert np.all((masked_tokens >= 0) & (masked_tokens < config.vocab_size)) def mask_type_count(tokens, mask_lm_positions, labels): masked_tokens = tokens[mask_lm_positions[labels != 0]] true_tokens = labels[labels != 0] mask_types = Counter({"103": 0, "same": 0, "random": 0}) mask_types["103"] += np.where(masked_tokens == 103)[0].shape[0] mask_types["same"] += np.where(masked_tokens == true_tokens)[0].shape[0] mask_types["random"] += np.where((masked_tokens != 103) & (masked_tokens != true_tokens))[0].shape[0] assert sum(mask_types.values()) == masked_tokens.shape[0] return mask_types def check_nsp(nsp): assert (nsp == 0) or (nsp == 1) @pytest.mark.skip_longtest_needs_dataset def test_wikipedia_dataset(): args = "--config demo_tiny_128".split() config = transformers.BertConfig(**(vars(parse_bert_args(args)))) config.vocab_size = 30522 config.input_files = ["data/wikipedia/128/wiki_000.tfrecord"] num_tokens = 0 replacement_counts = Counter({"103": 0, "same": 0, "random": 0}) opts = get_options(config) loader = get_dataloader(config, opts) for datum in tqdm(loader): tokens, attn_mask, types, mask_lm_pos, labels, nsp = datum tokens = tokens.numpy() attn_mask = attn_mask.numpy() types = types.numpy() mask_lm_pos = mask_lm_pos.numpy() labels = labels.numpy() nsp = nsp.numpy() for b in range(config.micro_batch_size): check_dimensions(config, tokens[b], attn_mask[b], types[b], mask_lm_pos[b], labels[b], nsp[b]) check_tokens(config, tokens[b], mask_lm_pos[b], labels[b]) check_attention_mask(attn_mask[b], tokens[b]) check_mask_lm_positions(config, mask_lm_pos[b]) check_labels(config, tokens[b], mask_lm_pos[b], labels[b]) check_token_type(types[b]) check_nsp(nsp[b]) replacement_counts += mask_type_count(tokens[b], mask_lm_pos[b], labels[b]) # Number of tokens, not including padding num_tokens += attn_mask[b, attn_mask[b] == 1].shape[0] # Test masked token proportions total = sum(replacement_counts.values()) for k in replacement_counts: replacement_counts[k] /= total assert 0.79 < replacement_counts["103"] < 0.81 assert 0.09 < replacement_counts["same"] < 0.11 assert 0.09 < replacement_counts["random"] < 0.11 assert 0.14 < total / num_tokens < 0.16 # should be ~0.15