Issue title: A problem while training the model
 Issue body: When training the model, the program often stops at an iteration without error information. At this time, the memory is occupied, but the GPU utilization is 0.The program also stops outputting. I am using 4 pieces of 1080Ti.
 Comments: 
 Comment 0: Same question, have you solved it?
 Comment 1: It's been a long time, I probably remember that my problem was because there were corrupted images in my training set, and the training code read data through multiprocess, so the error message wasn't thrown
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