My children (both adults now) always had homework during school holidays, for most subjects. One year it was the equivalent of 2-3 hours a day 7 days a week for the 6 week summer holidays, and to my knowledge when they handed it in, it didn’t even get looked at.
But on the plus side, it kept their brains working during the holidays, kept them in study mode, and they both achieved very good grades at GCSE and A level.