I am getting similar results to the course notebooks but generally much slower. For example on lesson3 retraining the dense layers takes 17 seconds per epoch in the course notebook. However my notebook is taking 31 seconds.
EDIT: and in the augmentation model @jeremy notebook is 4 minutes. Mine is taking 11 minutes per epoch.
@jeremy are you using AWS P2? If not then what is your setup? If you are then any idea what could be causing my slow timings?