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Weaving processes dynamically with top command.

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So while the PS command can reveal a lot about what the machine is doing, it provides only a snapshot

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of the machine state.

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At the moment of the command is executed.

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To see more dynamic views of the machine's activity.

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We use the top command like this here, so the top command displays a continuously updating by default

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every three seconds display of the system processes listed in order of process activity.

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So the name top comes from the fact that the top program is used to see top processes on the system.

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So the top display consists of two parts a system summary at the top of the display, followed by the

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table of processes sorted by CPU activity.

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So here the system summary contains a lot of good stuff.

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As you can see here.

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Let's actually understand what these are.

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So here we have top.

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So this is the name of the program here and here, as you can see here, we have actually let me get

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my marker here so you can see better.

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Here.

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So here, as you can see here, this is the current time of the day.

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This is the current time of the day.

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Right.

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And we also have the oops.

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Let me here.

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We also have the OP nine minute here.

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Obviously, it says this is a called op time.

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So it's the amount of time since the machine was last booted.

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So in this example, the system has been up for nine minutes.

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And we also have this user here.

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This is a there are this means that there are one logged in user.

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And as you can see, it's a typhoon here, which is my main user account.

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And we also have the load average here.

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Load average.

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This load average refers to the number of processes that are waiting to run, and that is the number

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of processes that are in a runnable state and sharing the CPU.

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So three values are shown here.

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So each for a different period of time.

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And the first is the average of the last sixth here, last 6/62.

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So the next here, here, this is the last 60 seconds average of last 60 seconds.

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The next is the previous five minutes and the finally here.

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So this is and 0.03 is the final of 15 minutes.

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So values less than 1.0 indicate that the machine is not busy here.

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As you can see here, my machine is not busy right now because our values is less than one in this case,

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0.12, 0.10 and 0.3.

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And as you can see, it changed to 0.10 right now.

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And we also have the tasks.

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The tasks here tasks.

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So this obviously says that the tasks is summarizes, summarizes the number of processes and their various

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process status.

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And we also have the CPUs.

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And let's actually this task, as you can see, the 192 is total.

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One is running 191 is sleeping zero stopped, zero zombie.

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And here, as you can see, these are the tasks that I use in my system.

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And we also have the CPU.

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So this is the CPU.

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This row describes the character of the activities that the CPU is performing here.

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So now I will explain what these tabs and information that the CPU tab provides us.

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The firstly here, as you can see here, us that written here, so the US that written here means that

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here in this case it's 0.6, 0.6% of the CPU is being used for user process here.

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As you can see, 0.5, 0.3 and so on.

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And we also have see here.

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So this is and right now is 0.8, 0.3 here.

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So this is the present of the CPU is being used for system kernel.

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So it's a kernel.

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Colonel.

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And we also have an AI here.

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So 0.0 an AI.

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So this 0.0 in this percent of the CPU is being used by nice, low priority processes.

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So as you learned the what's the nice and low, what's you in previous lecture actually you learned

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about high priority priority and low priority processes in previous lecture.

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So in this case it's my CPU is used, its powers 0.0% for low priority process processes.

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And we also have this here.

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In this case, it's a 97.3 ID, this is the percent of the CPU is in idle mode.

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Like you turn on your car and it's just an idle mode.

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It doesn't do or go to anywhere.

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And we also have one point 0VA it's now probably 0.0 and here it's going to be 1.0.

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So this is a present of the CPU is waiting for input output.

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You also learned what the input output is in previous lectures and we also have mem mem.

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So this is a obviously this shows how physical ram, random how physical random access memory is being

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used here.

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This is A93 thousand 914 total.

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2,658.93.

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1004 15 used and 477.

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Miss buffered and chats.

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And we also have the swap tab here, swap information here.

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This this swap shows how swap space or virtual memory is being used.

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In this case, the total swap memory is 1024, which is one gigabyte and not used here.

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As you can see, total is right here.

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And this all of them is free.

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So 0.0 is used right now and avail mem here.

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So the top program accepts a number of keyword commands.

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So the most interesting are the h h command here.

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H keyword here.

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Let's actually try that h here, as you can see here with h command.

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Uh, this display, this command displays the help screen and Q command here.

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Q, Q keyboard When you press the key.

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Q keyboard Q key in your keyboard, you will get this you will get here, as you can see here.

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Now, we could from the top command here and let's try it.

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Age again and toggle the forest view.

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And here we.

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Here.

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We here, as you can see here, we have several commands that we will use in next lectures here.

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So.

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And so.

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Uh, both major desktop environments provide graphical applications that display information similar

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to top in much the same way that task manager in Windows Works and the top is better than the graphical

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versions because it is faster and it consumes far fewer system resources.

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After all, our system monitor program shouldn't be the source of the system slowdown that we are trying

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to track.

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So in next lecture you will learn how to control the processes in Linux.

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So I'm waiting you in next lecture.