[tiwil]

But my sleeping hour each day is not stable during weekends. Sometimes I sleep only around 5 hours. Sometimes I sleep more than 12 hours. It all depends on how much works I did during the previous day time. Usually I sleep more if I got tired after heavy works. I sleep less if I was not so tired when there were not much works to do during day time.

This is true for me ?, I usually when I get a holidays, I sleep can be 10-12 hours a day, and get a nap for 2-5 hours. Maybe my vacation is only filled with sleep.

When weekdays I get 6-7 hours each night, and I guess without a nap.