I've just started using atop to try to get to the bottom of some system bottlenecks.
I've found https://linux.die.net/man/1/atop which is very useful and explains most of what it does just fine.
What I'm curious about is what data atop shows when you very first launch it.
I ask because every time I launch it I have a red line that tells me swout 311826
, and a cyan line telling me disk usage is at 67%.
After 10 seconds they both clear and go back to low levels (or in the case of the PAG line disappears).
Is it telling me the worst statistic from the past hour? Day? Ever? Or something else?