I honestly don't understand how people manage on such little sleep, even 8-hours seems marginal. It seems to me that I need 80 hours total per week (average 10 per day). If I skimp on that by sleeping "only" 8 (or fewer) hours a day, I just end up sleeping in even more on the weekend to make it up.
I was diagnosed with sleep apnea, and putting me on a CPAP eliminated my snoring but did nothing for the duration of sleep I seem to desire. I typically wake 2-3 times in the early morning (that I am aware of) but I desperately want to get back into whatever I was dreaming about (hate leaving whatever I was urgently doing unfinished) and in the absence of interruptions I usually fall right back to sleep.
I the morning (after 10 or so hours) I don't feel refreshed at all, more bleary-eyed and hyper-sensitive to light and sound (no, I don't drink alcohol) with heavy, lethargic limbs that don't want to move. I also desperately want to get back into the last dream and finish whatever it was I was doing, which is extra-frustrating when the memory of what I was doing quickly fades leaving me with the vague sense that I was doing something really important but now I've forgotten what it even was.
The only thing that seems to help is a late wake-up time. It seems like if I can sleep in all the way until 7:00-7:30-ish I wake up much easier and it almost doesn't matter how late I go to bed. But of course that's incompatible with job-having.