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Two-level group convolution.
Youngkyu Lee1, Jongho Park2, Chang-Ock Lee1
1Department of Mathematical Sciences, KAIST, Daejeon 34141, Republic of Korea.
We introduce a novel two-level group convolution method to enhance convolutional neural network performance. This approach improves robustness with more groups and supports multi-GPU parallel computation.
Area of Science:
- Computer Science
- Artificial Intelligence
- Machine Learning
Background:
- Group convolution reduces computation time in convolutional neural networks but suffers performance degradation with many groups.
- Standard convolution is computationally intensive, dominating neural network training time.
Purpose of the Study:
- To propose a new convolution methodology, "two-level" group convolution, that maintains performance with an increased number of groups.
- To develop a method suitable for multi-GPU parallel computation and robust against performance degradation.
Main Methods:
- Interpreting group convolution as a one-level block Jacobi approximation from numerical analysis.
- Introducing a coarse-level structure to promote intergroup communication without creating bottlenecks.
- Ensuring additional work from the coarse-level structure is efficiently processed in distributed memory systems.
Main Results:
- Demonstrated robustness of the two-level group convolution method with respect to the number of groups.
- Verified efficient processing of the coarse-level structure in distributed memory systems.
- Numerical results confirm the proposed method's superiority over existing group convolution approaches.
Conclusions:
- The proposed two-level group convolution effectively addresses the performance degradation issue associated with increasing group numbers.
- This method offers significant improvements in execution time, memory efficiency, and overall performance for deep learning models.
- The approach is well-suited for multi-GPU parallel computation, enhancing scalability.
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