Buggy macbook kernal task what to do?

Question

macbook

So the problem is this. A macbook air of mid-2012 fell into my hands. When using a poppy, it lags wildly, and a heavy load of the kernal task is visible in the processes. But at the same time on windows it works quite well. I tried to delete system files (I found a guide on the Internet), the laptop does not heat up (except that it is slightly warm), the battery is new (expensive). I don’t know what it is connected with, I wore it to the service, they said it was necessary to change the legs of the cooler, they changed it, it didn’t help.

Answer 1

kernel_task, as they say on the Internet, is like "Inactivity" in Windows.
"Wildly lag" can be from anything.
At least there is no input data: what is the axis, what is the hardware, what else is there in the processes?