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You now that you know what to
look for in top, let's talk about management

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options in top. And in order to
manage something, I'm going to run some processes.

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Dd well, sudo I'm going to use
sudo dd if is dev 0 of is

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dev null and I want to run
it as a background process and I want

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to run it a couple of times,
then I'm getting back to top. And as

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I'm going to manage processes, I definitely
need to run this with pseudo privileges.

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So here we are back in top, and this
time we can see that serious business is going on.

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Load average is
currently at 2.53.

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And as you can see, there's a
couple of DD processes that is quite

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active, and that means that you might
want to do something about it, because

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all these active processes don't leave
much space for other processes anymore.

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The most common task that you might be interested in
doing from top is to send a signal to your process.

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The K command, which is short
for kill, allows you to do that.

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That sounds pretty bad, but really signal
is an instruction. The first thing that

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you are going to be asked after
pressing K is which pid you want

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to kill and it defaults to the
top pid. And that's okay with me.

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So I'm
pressing enter.

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So next we can see that it's asking
for a signal. Now, what is a signal?

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A signal is the instruction from
the operating system, and by default

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it's sending sigterm. And sigterm means
process, you need to go away.

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The process cannot ignore this request
and that is why it will

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be removed from the process table.
That's what we see right here.

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So killing is one of the things that you can
do from top. Another thing that you can do from top

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is change the process priority. So we can see a
couple of dd processes right now. 3907, 3902 and 3964.

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And in the third column we can see
that all of them have a priority of 20.

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Now, if you want to
make one process more equal than

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the other processes, you can
use R for re. Nice.

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So now it's asking for the pid that I
want to renice. So I want to Renice 3907.

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Let me press enter and then it's going
to ask the value that we want to use.

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Now when you are renicing, you can
Renice from minus 20 to positive 19, where

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minus 20 means that you are getting
the highest priority. So it will go before

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other processes and positive 19 means that
you are lowering the priority of this process.

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Well, I can see that 3907 is
already quite busy as it is, so I

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am going to give it positive 10
and then I'm pressing enter to apply that.

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You should know that if you
want to use a negative nice value,

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you need to be a root
user, so you need administrative privileges, and

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ordinary non root users can only
lower the priority of their processes.

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So here we go. You can see that 3907
has changed its priority and now it's listed in

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the third column with a PR, which is
priority of 30 and a nice value of 10.

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And as you can see, it's almost disappearing. And that's
what you can do in top to manage your processes.

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Let me use Q to get out of
there, because for now this is enough about top.