Extremely slow data loading

[Hcyang-NULL]

Thanks for your sharing!

I encountered a problem when training MAC: Dataloader is extremely slow to load data even if I increase the num_work value. In the case of num_work equal to 16, a batch of data takes about 8 minutes to load. So I want to ask if you have this problem or if there is something wrong with my settings.

I noticed that the number of uncompressed visual feature and visual activity concepts tar files is huge (the former is about 940,000 and the latter is about 640,000).