Thanks for reply~
But i consider that the state for GN need to be stored is a Bx(C/G) tenosr while Cx1 tensor for BN.(p.s G is channel number for each group) . I think this tensor only occupies tirvial memory. However, for my network, it consumes 4G memory for BN while 6G memory for GN( B=16 G=16). Are there any extra states with big size (like feature map) need to be stored for GN?