Parallel multitask cross validation for Support Vector Machine using GPU

The Support Vector Machine (SVM) is an efficient tool in machine learning with high accuracy performance. However, in order to achieve the highest accuracy performance, n-fold cross validation is commonly used to identify the best hyperparameters for SVM. This becomes a weak point of SVM due to the extremely long training time for various hyperparameters of different kernel functions. In this paper, a novel parallel SVM training implementation is proposed to accelerate the cross validation procedure by runningmultiple training tasks simultaneously on aGraphics ProcessingUnit (GPU). All of these taskswith different hyperparameters share the same cache memory which stores the kernel matrix of the support vectors. Therefore, this heavily reduces redundant computations of kernel values across different training tasks. Considering that the computations of kernel values are themost time consuming operations in SVM training, the total time cost of the cross validation procedure decreases significantly. The experimental tests indicate that the time cost for the multitask cross validation training is very close to the time cost of the slowest task trained alone. Comparison tests have shown that the proposed method is 10 to 100 times faster compared to the state of the art LIBSVM tool. © 2012 Elsevier Inc. All rights reserved.