Yes, that will be 2 full iterations. And you can even disregard the shuffling of the data indices by the dataloader and follow your own stragety in the next function. For examle irrespective of ehat index the dataloader sends, you can calculate your own index based on your dataset, that way your strategy would not be affected even if you put a huge nunber in len. It’s all subjective how you want to design your dataset.