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Hello, welcome back.

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And this lesson, we going to give an introduction to real time operating systems, so.

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What is an operating system?

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Basically, an operating system is resource manager, it's money, just resources for the various part

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of the system.

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We see it's a real time operating system when this resource manager can guarantee deadlines.

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For instance, let's say I have a program and the program is supposed to take a number of actions,

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a program for an autonomous vehicle, it's supposed to take an action such as turn.

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But before it takes such an action, it first needs to read the data from its leader saying so and check

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the status of it.

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After that, he has to read from it radars.

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And so and then he has it has to be read from its camera.

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And then based on the data values of these various sensors, a particular action will be taken.

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If we are to design this in a real time operating system and we want all of it to occur.

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To OK and meet a particular deadline, what we would do is we would place them in their own tasks.

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Such as it's arranged over here, over here we have task one, and this task is just take action.

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It's just says take action and then come back to the top, take action.

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And this task is just for reading to lead us.

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I started this other one is for reading their reader studies and this one is for reading the Congress.

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That is, these are all separate tasks.

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A Real-Time operating system allows us to arrange a program like this.

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Otherwise we would have to keep all of this in, let's say, one one task and then we could run it sequentially.

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In a way, we would talk more about it later, would describe the differences between Real-Time operating

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system and the other way that we write our code.

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But where you need to remember is a real time operating system as a resource manager that guarantees

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deadlines.

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OK, so now let's take a look at some performance metrics.

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We said it guarantees deadlines, what we mean by that sort.

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So deadline simply means deriving the right result within a set of time constraints.

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That is the deadline.

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And another way to to check the performance of the real time operating system is to check its reliability.

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And reliability means running in a predictable way with a guaranteed response.

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So if you want to check the performance of a Real-Time operating system, first, ask yourself, does

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it meet the deadline set is a reliable.

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Does it always run in a predictable way with a guaranteed response?

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If these two metrics are parsed, then you would see, OK, having a Real-Time operating system here.

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Of course, the other metrics, but these are the the two two of the most important ones.

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Right.

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Now, let's take a look at another popular term we'd come across known as the kernel, so we we have

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already defined what a real time operating system is.

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Now, what is Akino?

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Akino is the core of the Real-Time operating system, and the kernel has control over every aspect of

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the realtime operating system.

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And it's it's responsible for booting into the right communication, synchronization and thread scheduling.

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So Real-Time Operating Systems have something known as the threat scheduler.

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Or the task switcher, this would switch the currently running task.

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From the process of bringing a new one, these components are part of what we call the colonel.

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So the kennel is like the call, if you want to remember what a kennel is, you can simply describe

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it as the core of the operating system, in our case, the core of the Real-Time operating system.

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And over here, we've stated for examples of some of its responsibilities.

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Right.

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And the next lesson we should talk about a very important concept in real time operating systems known

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as context switching, so I'll see you in the next lesson.