Pruning Attention Heads of Transformer Models Using A* Search: A Novel Approach to Compress Big NLP Architectures

Recent years have seen a growing adoption of Transformer models such as BERT in Natural Language Processing and even in Computer Vision. However, due to the size, there has been limited adoption of such models within resource-constrained computing environments This paper proposes novel pruning algorithms to compress transformer models by eliminating redundant Attention Heads. We apply the A* search algorithm to obtain a pruned model with minimal accuracy guarantees. Our results indicate that the method could eliminate as much as 40% of the attention heads in the BERT transformer model with almost no loss in accuracy.