language: en
thumbnail: null
license: mit
tags:
- question-answering
- null
- null
datasets:
- squad_v2
metrics:
- squad_v2
widget:
- text: Where is the Eiffel Tower located?
context: >-
The Eiffel Tower is a wrought-iron lattice tower on the Champ de Mars in
Paris, France. It is named after the engineer Gustave Eiffel, whose
company designed and built the tower.
- text: Who is Frederic Chopin?
context: >-
Frédéric François Chopin, born Fryderyk Franciszek Chopin (1 March 1810 –
17 October 1849), was a Polish composer and virtuoso pianist of the
Romantic era who wrote primarily for solo piano.
bert-large-uncased-whole-word-masking model fine-tuned on SQuAD v2
This model was created using the nn_pruning python library: the linear layers contains 25.0% of the original weights.
The model contains 32.0% of the original weights overall (the embeddings account for a significant part of the model, and they are not pruned by this method).
With a simple resizing of the linear matrices it ran 2.15x as fast as bert-large-uncased-whole-word-masking on the evaluation. This is possible because the pruning method lead to structured matrices: to visualize them, hover below on the plot to see the non-zero/zero parts of each matrix.
In terms of accuracy, its F1 is 83.22, compared with 85.85 for bert-large-uncased-whole-word-masking, a F1 drop of 2.63.
Fine-Pruning details
This model was fine-tuned from the HuggingFace model checkpoint on SQuAD2.0, and distilled from the model madlag/bert-large-uncased-whole-word-masking-finetuned-squadv2. This model is case-insensitive: it does not make a difference between english and English.
A side-effect of the block pruning is that some of the attention heads are completely removed: 155 heads were removed on a total of 384 (40.4%). Here is a detailed view on how the remaining heads are distributed in the network after pruning.
Details of the SQuAD1.1 dataset
| Dataset | Split | # samples |
|---|---|---|
| SQuAD 2.0 | train | 130.0K |
| SQuAD 2.0 | eval | 11.9k |
Fine-tuning
Python:
3.8.5Machine specs:
Memory: 64 GiB
GPUs: 1 GeForce GTX 3090, with 24GiB memory
GPU driver: 455.23.05, CUDA: 11.1
Results
Pytorch model file size: 1119MB (original BERT: 1228.0MB)
| Metric | # Value | # Original (Table 2) | Variation |
|---|---|---|---|
| EM | 80.19 | 82.83 | -3.64 |
| F1 | 83.22 | 85.85 | -2.63 |
{
"HasAns_exact": 76.48448043184885,
"HasAns_f1": 82.55514100819374,
"HasAns_total": 5928,
"NoAns_exact": 83.8856181665265,
"NoAns_f1": 83.8856181665265,
"NoAns_total": 5945,
"best_exact": 80.19034784805862,
"best_exact_thresh": 0.0,
"best_f1": 83.22133208932635,
"best_f1_thresh": 0.0,
"exact": 80.19034784805862,
"f1": 83.22133208932645,
"total": 11873
}
Example Usage
Install nn_pruning: it contains the optimization script, which just pack the linear layers into smaller ones by removing empty rows/columns.
pip install nn_pruning
Then you can use the transformers library almost as usual: you just have to call optimize_model when the pipeline has loaded.
from transformers import pipeline
from nn_pruning.inference_model_patcher import optimize_model
qa_pipeline = pipeline(
"question-answering",
model="madlag/bert-large-uncased-wwm-squadv2-x2.15-f83.2-d25-hybrid-v1",
tokenizer="madlag/bert-large-uncased-wwm-squadv2-x2.15-f83.2-d25-hybrid-v1"
)
print("bert-large-uncased-whole-word-masking parameters: 497.0M")
print(f"Parameters count (includes only head pruning, not feed forward pruning)={int(qa_pipeline.model.num_parameters() / 1E6)}M")
qa_pipeline.model = optimize_model(qa_pipeline.model, "dense")
print(f"Parameters count after complete optimization={int(qa_pipeline.model.num_parameters() / 1E6)}M")
predictions = qa_pipeline({
'context': "Frédéric François Chopin, born Fryderyk Franciszek Chopin (1 March 1810 – 17 October 1849), was a Polish composer and virtuoso pianist of the Romantic era who wrote primarily for solo piano.",
'question': "Who is Frederic Chopin?",
})
print("Predictions", predictions)