[celerrimus]

Quite good question. I used to sleep 8~9 hours, less (and more as someone already pointed) meant i was not very productive, made more mistakes, and i was irritated whole next day.

But for more then a year I'm a father, so now much changed. Now I sleep 5-7 hours, often with breaks during night. For example, tonight we had some problem and o lot of crying due to daughter's ear infection. I sleep 5,5hrs with 2 breaks.

How do I feel now? Unexpectedly well. I need little longer sturt-up in the morning - plus good coffee. I know that my productivity, creativity, and susceptibility to errors are little down, but I can tell that my body switched to new scheme and it's not such a bad think as i thought.

Also, all my troubles with falling asleep, etc, all are gone now. I know that you can handle much more then you think :)