1
00:00:00,000 --> 00:00:10,880
So first thing that we need to do, we need to calculate the default rate on the slice

2
00:00:10,880 --> 00:00:16,440
is 100. That goes for services as well. So if I need system slice to be four times as

3
00:00:16,440 --> 00:00:29,320
high, I need system CTL set property on system dot slice. And the property is CPU weight

4
00:00:29,320 --> 00:00:39,400
is 400. So that is one. Then I'm going to run my system CTL start stress one dot service.

5
00:00:39,400 --> 00:00:44,639
It's very important to do this as a system D unit, because then you can be sure it's

6
00:00:44,639 --> 00:00:52,680
in the system slides. Next is the root user. I'm going to use DD. IF is dev zero. OF is

7
00:00:52,680 --> 00:00:58,919
dev null or better. Let me use well true so that we can see difference. Well true, do

8
00:00:58,919 --> 00:01:06,080
true, done. That's not a process that is going to generate a lot of overhead. Then

9
00:01:06,080 --> 00:01:12,760
I'm using top. And what do we see? We see that the DD process is getting 80% and the

10
00:01:12,760 --> 00:01:19,959
batch process is getting 20%. Interesting thing learned from this, a root shell process

11
00:01:19,959 --> 00:01:25,919
runs in the user slice, not in the system slice. You may have expected the root processes

12
00:01:25,919 --> 00:01:32,160
to run in the system slice. That is not the case. Now, before you are getting out of here,

13
00:01:32,160 --> 00:01:40,959
don't forget to get back to the original situation. First, kill all DD. Next, maybe do it from

14
00:01:40,959 --> 00:01:50,239
top. Kill the root batch process as well. That script that was just started. And that

15
00:01:50,239 --> 00:01:57,599
didn't work out all right. 4, 7, 5, 7. And what is going on? Well, I'm killing 4, 7,

16
00:01:57,599 --> 00:02:03,320
5, 7. And it comes back and comes back and comes back. Oh, no. Why does it come back?

17
00:02:03,320 --> 00:02:09,559
Because it's an infinite loop. Well true, do true, done. And I kill it. It starts again.

18
00:02:09,559 --> 00:02:19,919
Now it is gone. And next, I should not forget to set my default CPU weight back. And also,

19
00:02:19,919 --> 00:02:32,479
ECHO1, greater than, Sys, Bus, CPU, Devices, CPU1, Online. Because that will give you a 2-CPU system again.

20
00:02:32,479 --> 00:02:33,119
And that's all.