Processes have CPU usage when in "Sleep" status

I have processes showing CPU usage when they are in Sleep status, as seen in top or htop. How’s that possible?

EDIT: This link here says that there’s some overhead for inactive processes. But a) I get significant CPU usage (from 1 to 10-20% (out of ~800%)) per inactive process, and b) what’s the juggling overhead for inactive processes?

What do you interpret as “sleep status”?

If the system were sleeping you would have no display and no way to have top or htop providing output. Obviously the system is not sleeping when you see those results.

If you are referring to a “sleeping” process that is normally automatically controlled by the system and time shared for cpu processing time. Available cpu time is shared among the loaded processes and some are sleeping while others are active.

The link you shared explains this and when top displays cpu time for a process it is not sleeping at that moment of time.