Hi, thanks for your reply. Should the size be responsible for the cuda usage? The sizes of c.unsqueeze(1) and self.msfcae.scale_mu are respectively [3997696,1,10] and [20,10]. How to calculate the expected memory usage? Or could you please allow me to ask a question: why does it require extra cuda memory for minus operation on two existed cuda tensor? Will the required memory be released in next epoch or increased epoch by epoch? I do not understand the mechanisms behind this. Anyway, I should express my thanks for your continuous help.