CoLT5: Faster Long-Range Transformers with Conditional Computation

Joshua Ainslie, Tao Lei, Michiel de Jong, Santiago Ontanon, Siddhartha Brahma, Yury Zemlyanskiy, David Uthus, Mandy Guo, James Lee-Thorp, Yi Tay, Yun-Hsuan Sung, Sumit Sanghai


Abstract
Many natural language processing tasks benefit from long inputs, but processing long documents with Transformers is expensive – not only due to quadratic attention complexity but also from applying feedforward and projection layers to every token. However, not all tokens are equally important, especially for longer documents. We propose CoLT5, a long-input Transformer model that builds on this intuition by employing conditional computation, devoting more resources to important tokens in both feedforward and attention layers. We show that CoLT5 achieves stronger performance than LongT5 with much faster training and inference, achieving SOTA on the long-input SCROLLS benchmark. Moreover, CoLT5 can effectively and tractably make use of extremely long inputs, showing strong gains up to 64k input length.
Anthology ID:
2023.emnlp-main.309
Volume:
Proceedings of the 2023 Conference on Empirical Methods in Natural Language Processing
Month:
December
Year:
2023
Address:
Singapore
Editors:
Houda Bouamor, Juan Pino, Kalika Bali
Venue:
EMNLP
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
5085–5100
Language:
URL:
https://aclanthology.org/2023.emnlp-main.309
DOI:
10.18653/v1/2023.emnlp-main.309
Bibkey:
Cite (ACL):
Joshua Ainslie, Tao Lei, Michiel de Jong, Santiago Ontanon, Siddhartha Brahma, Yury Zemlyanskiy, David Uthus, Mandy Guo, James Lee-Thorp, Yi Tay, Yun-Hsuan Sung, and Sumit Sanghai. 2023. CoLT5: Faster Long-Range Transformers with Conditional Computation. In Proceedings of the 2023 Conference on Empirical Methods in Natural Language Processing, pages 5085–5100, Singapore. Association for Computational Linguistics.
Cite (Informal):
CoLT5: Faster Long-Range Transformers with Conditional Computation (Ainslie et al., EMNLP 2023)
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