So first thing that we need to do, we need to calculate the default rate on the slice
is 100. That goes for services as well. So if I need system slice to be four times as
high, I need system CTL set property on system dot slice. And the property is CPU weight
is 400. So that is one. Then I'm going to run my system CTL start stress one dot service.
It's very important to do this as a system D unit, because then you can be sure it's
in the system slides. Next is the root user. I'm going to use DD. IF is dev zero. OF is
dev null or better. Let me use well true so that we can see difference. Well true, do
true, done. That's not a process that is going to generate a lot of overhead. Then
I'm using top. And what do we see? We see that the DD process is getting 80% and the
batch process is getting 20%. Interesting thing learned from this, a root shell process
runs in the user slice, not in the system slice. You may have expected the root processes
to run in the system slice. That is not the case. Now, before you are getting out of here,
don't forget to get back to the original situation. First, kill all DD. Next, maybe do it from
top. Kill the root batch process as well. That script that was just started. And that
didn't work out all right. 4, 7, 5, 7. And what is going on? Well, I'm killing 4, 7,
5, 7. And it comes back and comes back and comes back. Oh, no. Why does it come back?
Because it's an infinite loop. Well true, do true, done. And I kill it. It starts again.
Now it is gone. And next, I should not forget to set my default CPU weight back. And also,
ECHO1, greater than, Sys, Bus, CPU, Devices, CPU1, Online. Because that will give you a 2-CPU system again.
And that's all.