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0:32
OK. So they're calling on the transcription has started, and as I say, I will make them available. Some of you may already have seen that we have a YouTube channel where the previous lectures are are placed, and I'll placed these ones in the same place.
0:53
So what is the operating systems module? Will what I want to do is add on to what you did with Henry last year when you did computer systems.
1:05
And take that and build on it to help you understand how a modern operating system is created.
1:14
The kinds of choices that we have to make when we're doing that. The effects of those choices, and why different operating systems make make different choices.
1:26
Sometimes it can be really easy to understand.
1:30
If you're sitting there with CR. A Windows desktop. You may have a hard disk in there.
1:38
Not a a difficult decision to make to allow Windows to the operating system to support hard disks.
1:46
Less likely that you're going to have a hard disk in your Android phone, so the Android operating system. Not so happy about supporting hard disks because there's no point in doing so. It's made a choice and a lot of the stuff that we will be talking about today is about choices.
2:06
It's about the canes of things. That we have to do the trade-offs as well. We all want operating systems and programs and computers that goes quickly as possible, but we also want them to do as much as possible. And do as many things as possible, and he can't have all those things at once. You have to make trade-offs and we'll talk about that as well.
2:30
So when you come out of this, hopefully you'll understand about those structures, those functions, how they all work together and to understand all the components that go into making. An operating system.
2:47
No, unusually for.
2:50
Certainly for me and I think for the. For all of your modules.
2:56
I'm asking you to buy a book.
3:01
The book is called Operating Systems concepts.
3:17
And I've put a link to on the screen there and I'm just going to bring it up. Lessons Amazon other.
3:26
Vendors are available.
3:30
So you'll see the operating systems concepts is.
3:38
Quite expensive. So don't buy that one.
3:42
OK, two pile up. I don't want you to spend it. Is £6.00 on our book. I don't even want you to spend £35.78 and a book.
3:53
What want you to do is go in.
3:57
Amazon, not somewhere else.
4:00
And find. Previous editions.
4:08
You'll see that they all have dinosaurs on the front.
4:14
So guther.
4:17
Pained.
4:19
As I say, a previous version.
4:22
What? Excuse me. And I don't mind which.
4:29
And buy a second hand copy.
4:32
No.
4:34
The thing about the book is operating systems are.
4:41
Similar, so things change. Of course they change. But the underlying principle stay the same, and it's part of the reason I want you to buy this book. And here the first one I've clicked on and you can spend more time on it here. It's down to five or for a used version.
4:58
I bought mine for a penny plus £2.80 postage. So look around and get a get a cheap one if you really can't afford the price of a pint.
5:06
Those copies in the library. But I really do recommend you buy it because it will be helpful not just for this module but for other modules and in your career. Because as I see, operating systems certainly change that much.
5:20
The underlying concepts haven't changed that much, and all the material that we are going to cover will be in all the editions of this book. The newer editions actually give.
5:33
Examples of different operating systems, so older versions might say here's a Solaris Unix operating system and how it works and a newer version might say here's a Windows 7 operating system and how it works. You don't need those chapters.
5:49
But the the basic stuff is similar in all of the editions, so by a cheap version.
5:58
But please do buy the cheap version because all of the stuff that we are doing is based on this book. OK. So even though lectures, the slides, they're all coming from this book.
6:10
So that will be really helpful for you to have. So spring a fiver or if you can do it spring a penny plus 280 postage and buy the book please.
6:23
Because the. Books are the same.
6:30
What maybe slightly differently ordered, what I've done is created a document that lets you see where we're working now. You've had an e-mail and all of the module materials are in that link from that e-mail.
6:49
So it's and something called a OneNote. Document, so one note. It's like word on steroids. It's not just text. It can have. Images and spreadsheets and presentations and YouTube videos.
7:08
There's a YouTube channel for example for this module.
7:13
So all of the information that you need for this module.
7:18
As in this one note notebook and you'll see that it's organized by chapter. So there's a chapters in my edition of the book.
7:29
And the material that we're going to cover, so there's processes. And you can see you've got a presentation, we'll get tutorials about them.
7:40
And.
7:44
Different things to do different tasks. OK, it's all in this document. So you'll get access to everything that we're going to use from day one. So you can not only can you work ahead, you should work ahead. So today is the introduction. Next week we start on system structures.
8:04
So you should read that stuff. And before we get there. Thanks. Connors. Connors found her. A cheaper one.
8:18
So yeah, read the stuff before you get to the next lecture, so you should be reading system structures before next week and what it means is rather than coming in here, let me just talking at you.
8:30
It means we can cover what's in there, but you've already read it. You've already thought about it. Means you can ask me questions about it while we're in here.
8:38
Note to help you better understand. The different editions and to understand what we're doing, one of the documents that we've got in this one note notebook is the syllabus. Basically what we are doing and when.
9:01
So this is Week 2.
9:07
You UWS starts weeks at number one with the induction week. So the first teaching week is number 2 and you can see that's the week beginning the 12th of the 9th. So for you guys in the lineup, sure, that's actually the date of your lab as well. You guys and Paisley, it's not. So I've just put the week beginning to cope with the different. A campuses.
9:31
And you'll see what we're doing.
9:34
Week by week.
9:36
So this is.
9:39
Semester week two. So our first week we are doing the introduction chapter. Next week we're doing the system structures chapter. Next week, the week after that, we're doing process concepts and so on.
9:51
No, one of the reasons I put that there with the chapter names is it different editions sometimes swap the chapters about the content is pretty much the same, but they swap the order the Chapter 3 might become chapter 6.
10:04
As long as you've got the names, you should be able to find it in your book and. Hey. And be able to.
10:10
Get the information now.
10:15
Final thing about the book. You have said it will be useful for this module for other modules and throughout your career, and that's true.
10:23
And part of the reason for that is it's a very comprehensive book and I'm meant to bring my copy, and I haven't. But it's, you know, it's this thick. It's a big book.
10:34
And we're not going to cover all of that book.
10:37
And the second you're module. So one of the other things I've put on there is the sections that we're not doing.
10:46
So you can see the other in Chapter 2. We're doing up to 2.5. But 2.62 point eight point 2.9 we're not doing OK, so we're cutting out a lot of it.
10:59
Ryan's asked, does it matter what additional year? Nope, it doesn't. That's exactly what I'm saying now. It doesn't matter what addition, what year the core material is the same. Just forget the cheapest copy that you can find. You won't be disadvantaged.
11:17
OK, so you've got. What we're doing every week, you've got the chapter.
11:23
And you've got what we're missing sometimes. Actually, we miss out whole chapters. So we're not doing the chapter on synchronization.
11:31
All the chapter on deadlocks. They're just not happening.
11:37
OK, so you've got all the materials. You know exactly what we're doing. You know the order that we're doing in it, doing it in and you've also got when the assessments will be due. And I'll talk a little bit more about the assessments after.
11:52
So if you haven't yet accessed this OneNote notebook leads to, I sent you all out an e-mail with a link to it.
12:02
And that e-mail was also an invitation to join our team. Not everyone has done that yet. If you haven't done it, please do.
12:13
And part of the reason for that is if you join our team.
12:18
I've actually put those things into the team as well, so there's a link direct to that OneNote notebook. And our team, now you can see exactly the same document, albeit loading very slowly. Because I've got very old machine. So all the stuff that you need is on teams.
12:38
So if you haven't yet joined our team. Please do not link again was in the e-mail.
12:53
Ohh, happy with that. I'm not seeing any more questions in the chat. I'm not seeing any hands.
13:01
OK.
13:06
Sure. Ohh Davide butter already. Always ahead of the covers, David.
13:13
And.
13:18
So all the materials. Out available on Moodle to speak with it says there so you'll know that the university is changing its VLE.
13:30
So we used to use Moodle which is what it mentions there. Now we use our.
13:38
Now the problem is that Ella doesn't support. Uh, some of the assessment types that I do.
13:47
So rather than having our. On Moodle.
13:52
And teams.
13:54
That's why all the module materials are on that OneNote notebook, because it just means I can link to it from wherever. And I I can't even remember. I think I put a link to it on our.
14:11
So.
14:13
We are still using.
14:17
Middle. But we're not using it for the module materials that we are using it for the assessments. So if you go to middle now. You see the all we have is tutorials, tests. And assessments.
14:37
OK.
14:39
I've taken out all the module materials and they're all in that one note notebook.
14:44
And if you're wondering what was talking about in terms of the e-mail that I sent you, I basically copied it into Moodle as well. And if you haven't got the teams invitation.
14:55
There's the so you can follow those instructions there. So I've put them on there too.
15:03
And again, if you're not sure where Moodle is, it's at my.uws.ac.uk, but of course you'll know that, cause I've put that into the e-mail as well.
15:18
Yeah, it's there. But also just like with the module materials I've linked to in teams.
15:29
I won't bother logging in.
15:32
And.
15:34
So you caught links everywhere.
15:38
And David's asking for a copy of the OneNote so that you can have a local copy.
15:43
And Connor's giving them the link and what Connor's giving them is a link to the notebook. That's correct. And I'm not sure at the moment whether you can copy from that or whether I haven't given you the rights to. And the answer, David, is yes, if you want something, I'm happy to supply it. And.
16:05
What I'm trying to remember is there was an issue with.
16:10
There was an issue with permissions in that they're not very fine grained. And that I could either let you look at the notebook, or I could let you edit it, and there's nothing in between, so I couldn't let you copy bits out of it. I think that's.
16:24
I think that's.
16:26
I think that was the issue, but more than happy to. I. Give you copies over.
16:33
And in fact, what I'll do is. I will or something on teams called a class notebook and I I'm I should be able to copy them into that class notebook and then you get your own copy. So I'll make a way note and I'll do that.
16:52
Connor sent a link which isn't the module. Materials. It's a student information, so those general information as well.
17:04
Again, you had a link to this and it's all the sorts of stuff that's general and it's not even as send this to all my students for all modules at all levels. So it's all this stuff about academic information and plagiarism and past Marks and.
17:22
Accessibility and calendars and teams and. Referencing it and just kind of general information that's helpful to have as a student. So csend it to all of my students to give them access to all of this.
17:37
And particularly when you're going to be doing assessment that requires referencing, it just means all the stuffs there.
17:46
And again, it's all there from day one. That said, I might add things to it.
17:52
So a lot of these pages have come from people asking me questions. And I've created a page to answer the question so that it's there for future reference and if you ask me a question I might point to this and say it's in the student information. So go read it.
18:08
So if you ask me about.
18:17
Everyone.
18:19
Or how to access the library?
18:22
Or.
18:24
How to go into Moodle?
18:27
All the things are in there so please have a look at them first before you ask the question.
18:39
I've been asked for the code for. Teams. So if you don't have the code.
18:48
That's it there and I'll just put it in the chat. So you should be able to join the team and just by joining the team and putting in that code. So go to teams, make sure you're logged in using your UWS credentials.
19:04
Join the team and then enter the code and you'll be there.
19:08
And.
19:12
He was asking for that because of enrollment issues and that's again part of the reason to do it this way. It means that everybody can get access to things even if we still have some slight enrollment issues.
19:25
And it just means I can give you all the stuff without. I'm having to rely on it being accessed. So for example, the module materials.
19:34
Don't require any sort of credentials at all, and actually just kind of thinking there from David. That's part of the reason I don't let you copy it or edit it because anybody who has that link can look at it, which is fine. I don't mind anyone looking at it, but I don't want just anybody editing it.
19:50
But it means that if you're not enrolled, it means you can access to materials and you're not falling behind.
19:59
OK, so all the materials available not on Moodle but on the OneNote document and there's a link to that on our team and in the e-mail and it's all relevant.
20:12
Except where explicitly mentioned that it's not.
20:19
So it's all there for a reason.
20:27
Having said that, I've. Explicitly said synchronization isn't in this course, but I have left in the slides for synchronization. So we will be doing them in this class. I won't be covering them, but you may be interested and you may want to have a copy of those. That presentation have a look at that presentation. That's fine.
20:50
But we won't be doing it and I've noted that we're not doing it similarly. Where you oops, where we have the presentations for ones that we are doing, you will see two.
21:04
Michaels. So in the same ways of noted that there's bits that were not doing, I've cut stuff out of the slides for the bits that were not doing so. There's a version for us.
21:15
But.
21:17
If you want to see the original version, I've put that in there too, just for your interest. OK, so there's a bet that we are doing. And then the bet that's original. And you'll see that on all of these chapters, our version. On the original book version. And invariably our version is much smaller.
21:43
All OK so far.
21:46
OK.
21:49
So all the sections are there for you to do and I would like you to turn up.
21:57
The stuff can own the chat. There's people asking questions. There's things that I'm saying that aren't up on these slides. You don't get to see it just by reading the slides.
22:08
Yes. All you had to do was read. Then I would tell you to go and buy the book and I'll see you in December for your assessment. Of course, that's not what we're doing. So please turn up to these things. Turn up for these online. Michaels. And turn up for your N person labs.
22:30
And we will take attendance. We are required by the university to take attendance.
22:36
And if you don't turn up well, you know the script.
22:42
OK, so how are we going to assess this?
22:47
There are a few things.
22:53
The first one is an individual coursework. So I've said that it's building on what we're doing. Computer systems at first year and I want to give you an idea of what's happening.
23:07
And when?
23:11
We have to do anything on our computer because it's very easy to get sucked into. What's our computer or it's a thing that has a Windows interface and you click a button and something magically happens. But of course that's not the case. As you know from last year. So one of the things that I want you to do.
23:29
Is create a program using those very low level instructions.
23:34
We are going to use something called assembler.
23:38
And you're going to create a program and assembler just to give you a flavor of what it's like.
23:46
Because what we think of is a very tiny thing to do, can actually take lots of assembler instructions, and it just reminds us that the operating system is doing an awful lot of things.
24:00
Man, I've got one note running and it presentations running and I've got teams running and it's showing me live video.
24:08
Think of all the things that are happening under the hood. For that to happen, think of all the things that the operating system has to juggle to make that happen. We sometimes forget. So our first assessment.
24:22
Is to make sure that we don't forget.
24:26
So now foster segment. And again, all the assessments are available from the beginning. All the explanations are on this OneNote document. Something called the Little man computer.
24:41
So this is worth 20 marks.
24:45
I I've basically said it up so that it's 100 marks, so basically every mark you get is 1% just to make it easy for us. So this is what 20 marks or 20% whatever way you want to think about it.
25:00
No, it's not exactly the hardest programming task in the world. Read the values and sort them.
25:08
And while just to smallest. So not exactly the the toughest task ever.
25:14
But you have to do it using machine code.
25:21
Sorry, no machine code. You have to do it using assembler.
25:27
Specifically, you have to do it using this.
25:32
Computer. So what we've got here?
25:38
I made a mistake there.
25:41
Ah, So what I do is I have Firefox running in. That's the. Umm proposal that I use whenever I'm giving one of these light tools and I do that because.
25:54
I've made the mistake before. Or just using my normal browser, which is cool. And while switching from page to page, people were riding my personal e-mail and stuff. So I thought well not do that and I'll keep it. I'll keep the the work stuff and I separate browser, so I use Firefox even though I use Chrome normally. But of course I just clicked on that, it opened up in Chrome in my machine just went. Umm.
26:18
So this is the little man computer.
26:23
And.
26:25
You can see that you can write assembler code.
26:32
This is the same block here LDA, STALDASTAINP BRZ. Those are all assembler codes you've done programming, so it's kind of like the lower level of programming.
26:47
This is the RAM.
26:52
Just as a Raman your computer with machine code, now it's in there as base 10, but this is actually binary and what this thing does.
27:04
You know, choose a slightly less complicated one, so here's a program that adds to numbers.
27:13
I NP anybody want to?
27:18
Take a stab at what IMP might stand for.
27:24
That's it. And put. You can put.
27:27
STA 99. And they want to take a stab at AST.
27:35
It may help if I see it's St. Space E. What me St may be.
27:45
Store. Store store so it's saying store.
27:51
And this mysterious E refers to the accumulator that you'll remember from last year.
27:57
Store whatever's in their accumulator and memory location. 99.
28:05
We've got another INTP or.
28:09
And put. And then we've got. Ohh, that's going to be tricky. Can you work out what the the command ADD might do?
28:21
Version. So good addition. So we're gonna add.
28:25
Whatever's in the accumulator, to whatever's in memory location 99. OUT.
28:37
Oh poop. Output. So we have taken to inputs, we've added them together. We've said output. And HLT.
28:51
Ohh correct. So what the little man computer does is shows you what's happening. It's gone away.
28:59
It knows that it's getting the instruction in location 0, so it's gone away and got it. It's bringing that back to the CPU.
29:11
And once it's got there, it's putting it into the instruction instruction name address register one.
29:21
And we've got a we thing you're saying inputs required, which isn't a surprise because our first command was.
29:28
And.
29:31
So it's taking my input and it's putting it into the accumulator.
29:36
And that's then looking at the program countenance saying next one is.
29:43
Instruction one. It also increments the program counter. It goes away to your arm, it gets whatever's in location one, because that's the next instruction, brings it back to the CPU and splits it up. Between an instruction and a register. So the instruction is 3 which is store. Whatever's in the accumulator and the address says 99, so it goes and grabs that eight and that 99 and sends them down. The address and data buses to store 8 and memory allocation linked to 9.
30:17
And at the end goes to get memory allocation too. So it sends two down there address line. To get whatever's in.
30:25
Member location too and it sends out back up the data bus.
30:31
And it's the same, not surprisingly, as was in. Man, you're location 0 because we got two inputs for both the same and it's looking for another input.
30:43
But give another input that comes in overrates what's in the accumulator.
30:49
And that stays. They'll just now and it goes away to get the next. Instruction which it knows is in memory Allocation 3, not forgetting to update the program counter so it knows the next one's 4.
31:04
What was it way gets the instruction? Brings back.
31:10
To the CPU slits up between the instruction and the address. And it says add, so it's add whatever's in memory location 9 to 9, so it has to go away to memory location 9 to 9. Find what's in memory location 99, send that back. Down the data bus, bring that in, add it to whatever's in the accumulator. Using the arithmetic and logic unit. And that gives us well in the accumulator. And then we should get the next instruction instruction four. It's also updated the program counter.
31:47
Who isn't gets instruction to four, brings it back in.
31:53
You'll be pleased to know that you can speed this up down here, so I'm going to speed this up a wee bit. Brings it back. He gets instruction 902902 means output, so it's output 12.
32:06
Which is a. Addition and then it goes and gets the next instruction which is instructions 0 which is halt and it stops.
32:17
No, you're not. We're getting really bored with my voice over there.
32:22
You can really bored with me telling you what was happening. It was a way to get instructions. Which bus it was sending them down, what it was doing with the the input and the output and the accumulator and the arithmetic and logic unit. And that's just for adding two numbers.
32:41
Think how much code is happening in your computer.
32:46
For it to peer group to progress the video that you're watching in the sound that you're hearing and the fact that you've got other programs running in the background so you'll get WhatsApp chatting to your mates saying it's Tony ever going to stop talking.
33:02
You've got all this stuff happening all at once really, really quickly and it's important we don't forget it. So that's what your first assessment is.
33:13
It's to write a small program using the Little man computer, so the. The online stuff, the first half of the module, the first six weeks or so is to do the LMC, so I will not be doing any more lectures on the LMC. You have got lots and lots of materials, lots and lots of tutorials. And I want you to run through these.
33:40
At your own speed.
33:43
So those written ones, and there's also video ones.
33:49
As I say, you can watch these actually in OneNote. You didn't have to go anywhere else.
33:55
So all the stuff in there and this is self-paced, so wanting to do this on your own.
34:02
But we'll be in the lab to help if you need.
34:08
When you've done it, you will submit.
34:15
Two things.
34:18
The.
34:20
Design of your program.
34:24
And I don't mind how you do it, is that if it's a flow chart, if it's suedo code, if it's whatever.
34:30
And also the.
34:33
Hold itself.
34:37
In other words.
34:41
This stuff here.
34:45
And what I'm going to do is I'm going to take that code, I'm going to input it into this. Implementation and I'm going to see if it runs.
34:55
OK.
34:57
That's why it's important you only use this version because there are tons of versions of the LMC out there. Only use this version because this is a version that will be tested on. It doesn't run on this one. I don't care if you tell me that it runs on the LMC that you built into Excel, and that's a thing. There is an Excel LMC.
35:17
It doesn't matter. Runner on this one.
35:22
The second thing is we'll be doing this in the lab, so we'll be looking at them in person. So I'll be coming her owned and asking you about them.
35:32
In other words, I would checking if you know what your code does.
35:36
So I might say, why have you put this instruction here? What's it doing? And it's just me trying to figure out whether you actually know what you're doing or whether you found a copy somewhere online. OK, so if you can't explain your code.
35:51
Then you have a problem. Andrew will be doing the same thing up thing at one upshire.
36:01
And it will then be marked using the marking scheme that's there.
36:05
So you'll see that there's a few headings LMC Command set program logic commented code, redundant code and so on and you'll get marks depending whether you don't have any, whether you've used some incomplete complete and so on. OK, so there's a a range of headings and you'll get marks based on them.
36:26
You can also get extra credit.
36:29
So if you want to extend your program for extra credit, you can. Don't forget to tell me what it is. So you make him in and say ohh. I have created one that copes with negative numbers or it can cope with. As many inputs as you want to give it or or you know, you tell me.
36:51
So if you want to get extra credit right, a better program and tell us about it.
36:59
So that is the first assessment.
37:04
Any questions on that?
37:13
OK. The second assessment is everybody's favorite because it's a group coursework.
37:25
Change this of whoa.
37:31
Ohh jeez.
37:34
Well, see The thing is.
37:36
What I have under my desk? Is.
37:41
Ah.
37:44
An add on.
37:47
It plugs into a USB connection. It's me pedals that lets me go backwards and forwards.
37:54
And and the presentations without using my mouse.
37:59
So if I'm locking up something we're paying, I don't use the mouse, I can use a petrol and I just managed to rest my foot when the pedal, so it ran all the way through that. Sorry about that.
38:09
So.
38:10
Second one, as I say, is everyone's favorite group assessment and it's a report.
38:18
There's a change from the slide, so instead of three, I am happy to accept 4.
38:24
So four pair group.
38:27
And an exceptional circumstances, by which I mean. We have the class numbers don't divide evenly by 4. I'll take groups of three or I'll take groups of five and I'll leave it up to you guys to choose.
38:45
No. I've got a whole big spiel on.
38:54
One note.
38:56
About.
39:00
Me choosing random groups.
39:05
And it's true. The reason it's there is because random groups work better for a whole lot of reasons.
39:18
But I'm acutely aware that you guys. Are working in slightly different circumstances.
39:27
So normally what would happen is you're taking the second year module, you kind of know people in the class because you had first year with them. And what I'm doing is trying to mix that up a week, but when we get to this point.
39:43
What?
39:46
I'm a wheel that you were working on line. I'm aware that don't know people as well. I'm aware that there are issues, so I'm actually gonna give you guys the choice.
39:57
So what I'm going to put on?
40:00
Moodle.
40:03
I what I call a self select. It basically sets up a whole bunch of groups and you guys can get together. So if you want to select a group on your own, you go into Moodle and say yeah, we're in this one together.
40:16
And if those people left over at the end, I will randomly split them so it's entirely up to you guys.
40:23
You can have random or you can self select I don't mind.
40:28
So I'll put that on Moodle and give you the chance to select over the the coming week. There's a question on.
40:37
The chat asking about how many are in the group. I think I've just answered it. It's four now.
40:43
But in exceptional circumstances, depending on the outcome of the division through your file, but four by preference.
40:53
So what is this group report? Well, we're going through. We're talking about processes and threads and CPU and memory management and all that kind of stuff. And I said right at the start that there is going to be.
41:08
Choices that we meet about these things.
41:13
So what I'm asking you to do is choose an operating system and explain the choices that have been made and why.
41:24
So.
41:26
Why has a particular operating system chosen a particular file system? And if you don't know what I mean by file system, don't worry, we're doing that in chapter 10.
41:38
Why has it chosen a particular way of implementing threads? And again, if you don't know about that, that's fine. That's what chapter falls for.
41:47
So what I want you to do.
41:50
Is link. The theories of the operating system and the choices that we make that we're going to cover in here 2A specific operating system.
42:01
And this year, it's going to be a Linux operating system.
42:07
And I actually don't mind which one you can choose whichever one you like. So if you have a preferred Linux operating system, great. If you've never heard of Linux, well, this is a good chance to get used to it.
42:20
And if you have thought ohh why not? So I have heard of that. I wonder what it's about even better because it gives you the opportunity to do it.
42:31
There is information and.
42:38
Not a good. OK.
42:43
It's not a good thing when I can't remember where I put things. There is information in Chapter 2.
42:49
About.
42:51
Installing Linux so you can do it virtually. You don't have to get a new machine, you can install it on a virtual machine.
43:00
On those links to lots of distributions.
43:03
And links to how to install things and the example I've given is Ubuntu.
43:10
As an example, it's a popular Linux distribution, but you don't want to use Ubuntu. Don't.
43:23
OK.
43:25
The all of I would suggest is this is.
43:34
Juan.
43:36
Holding to the syllabus.
43:43
At the end of November.
43:48
I suggest you don't wait until the start of November to start writing this report, but the reason I give you out nice and early is so that you can write your report as you go along. So as we learn about processes. Start right in your report on the processing section. As we learn about threads, start writing your report on the third section and so on.
44:13
And you can see with the marking system.
44:17
The marking scheme where you're going to get your marks from. And the pretty much correspond to the chapters, so there's a there's marks for the overall design. And that's really. This system structures chapter was marked for processes which is in the processes. Chapter ISIS scheduling that's also in the processes Charter. That's Mark's for threats. Those marks for memory management. Not your memory.
44:48
And then it stops. Why do you think it stops there?
44:53
Rolling and all the way down here.
45:10
Basically, I want you to to give you time to finish your report, so the stuff that is required in the report stops about here and that gives you three weeks after it to finish your report. So I'm not gonna teach you about something. And we can 11 and ask you to hand in your report and week 12. So the stuff that's in your report we stop. However, earlier to give you time to do it.
45:38
No, it has to be a professional report.
45:42
You're starting to.
45:46
Get further into your academic career. Excuse me. So it has to be referenced.
45:55
So it has to be properly constructed. Headers, diagrams, attributions, all that kind of stuff.
46:03
And again, if you don't know how to do it, that's why you've caught your student.
46:08
And formation one. Note that tells you about referencing. Why you have to do it. How to do it. And it's also got some tools to help you do that.
46:19
No, it's not a huge amount.
46:23
So those five marks for how you lay out the report, how you're difference? So it's not. Uh. Uh.
46:31
I deal breaker in terms of passing the the module. But just to get you started and thinking of us, because all become more. Part of what you're doing as you go along.
46:45
The question I always get asked is how long does a report need to be? And the answer I always give you is I don't know, you tell me.
46:54
You know what the marking scheme is? You know what I want you to cover. You know what it is? I'm asking you to do.
47:02
Now, if the question was slightly different, if you were in a job. And your boss said.
47:09
I've heard about Linux. Would it be feasible for us? To switch away and use a Linux system.
47:19
I know, I know, a company.
47:23
Great, my report and have it in two weeks. Your first question to your boss would not be fine. How many words do you want?
47:32
It would be OK let me cover all the information.
47:38
And that's what I want you to do here. I don't like to think in terms of what about the part of me, nothing else.
47:45
You could put in a diagram. And you all know the phrase.
47:51
So I'm not going to see how long the report should be. I'm gonna leave that up to your professional judgment. Over what needs to be covered. And make sure that it's all. Via.
48:10
Any questions on that one?
48:17
Nope.
48:18
Ohh happy. OK. The final one is class tests. So these are traditional tests.
48:29
The knowledge based.
48:34
And.
48:36
This is part of what's talking about earlier, so these are going to be on Moodle. So they've done online and they're marked automatically.
48:43
We'll also use it on campus lab time to do it so they'll be a particular date that you're giving, and we'll say this is when we are going to do it. So you will require to be there.
48:59
Questions can come from all of the stuff. That's all in the module materials module materials. Excuse me.
49:08
Now, part of the reason I do it online is I've got hundreds of questions.
49:16
So you'll get a question that might be on one of the sections. It might be on processes. And you may get three questions about processes, but those three questions will come from the 40 questions that I have in there. So you'll get three random questions out of those 40.
49:35
So you won't know what's coming. It also means that you can't just sit. And the lab and look at your neighbor and see what they're putting because they have different questions. Is too, more than likely.
49:48
As a question of it, maximum length for the group report. Again, there's no maximum length, but again, think about it in terms of.
49:57
A job. You want to.
50:01
Cover the material, but you don't want to just join on.
50:06
So again, I'll leave it up to you.
50:09
So the class tests will be randomized and there are two of them, and there's a reason for that.
50:19
There's two class tests because what I've done is split them up. So rather than doing all the charters and then giving you one big 40 Mark test. The first class test is for charters, one to five.
50:33
And the second class test is for chapters 8 to 13. So I've just split it up a wee bit rather than trying to remember what happened three months ago. I'm trying to do as it's fresh in your mind.
50:50
As I said, they are online. And that's part of the reason we use Moodle and one of the nice things about using Moodle is that as well as actually having the class tests, you can practice for them. So for every chapter.
51:08
There is a chapter taste.
51:14
Before I do this, I'm not even reading the questions, I'm just putting an answer. And move into next just to show you what we're doing. So this is the class taste you'll see. There are 20 questions here for chapter one.
51:34
So that was our choose 1 from 5. This is a true of false.
51:40
This is a multiple choice one again. This is choose more than one.
51:46
How many of these are true?
51:51
Here's a drag and drop. Take the words of the year and put them into the sentence to make the sentence make sense.
51:59
Take question.
52:01
OK, so there's a few different types of question in there.
52:05
But.
52:07
They're all online and they're all automatically mapped.
52:12
And part of the reason I point this out is if you can do the chapter tests. You will be fine with the class test, so every week when we go through a chapter. Do these. Chapter tastes.
52:28
And if you can do them. You will be fine.
52:34
In order to emulate the class test itself, you'll see different ones, so here's. Chapter taste, but here's an assessment.
52:46
Chapter test. Same kind of idea, but it's timed.
52:52
Just look at will be in class.
52:55
So you've got a time. What it's done is selected 5 random questions given you time and said right, go away and do these things.
53:10
Within the same sort of time frame you would have in the class test.
53:17
So if you have a spare 5 minutes sometime and you want to practice.
53:22
Go to the class test.
53:26
And when you do.
53:38
It will mark it and it'll tell you what you did. So it 1 here that was orange cause I got bits of it right.
53:45
I've got one here that was right because entirely by chance I clicked the right button. And I've got three here that are wrong because again, I just clicked whatever button came first.
53:56
So you can practice for these class tests. They are sorted by.
54:03
Whilst taste one so that's.
54:06
Chapters one through 5. And class test too. Chapters 8 through 30.
54:13
OK, so practice every week. And if those bets in there that you don't understand. Even though you've got the feedback, then ask us. That's why we're in the lab.
54:31
For those of you doing cybersecurity, we also have the ones for.
54:38
The cyber security.
54:42
Chapters.
54:49
Any questions on that?
54:56
No one? No thanks. It's cool. Thank you, Kyle. I think it's cool too.
55:03
OK. So 20% for the LMC, 40% for? The group report and two tests at 20 mark seats is another fault and that gives you your 100.
55:16
Usual thing past Mark is.
55:19
Apps. Past Marcus, 40. But each of those sections. So that's the individual bit, the group bit and the class tests you need to 30% in each of those to pass and part of the reason I do that is again I'm a will aware that in some groups there are freeloaders who will just try and pass using other people's work.
55:41
And by having the individual but also.
55:44
Count as to whether you pass it stops that happening hopefully.
55:50
But you don't want to be.
55:53
At 40%, you want to pass everything. And you want to get as best a mark as you can. Because it will affect your GPA.
56:03
So.
56:05
Don't up. Read the stuff you don't understand. Ask and what they are. If you have any questions. And actually I'm here right now if you have any questions. So are there any questions?
56:18
Yeah, I was just when done, but is this online lecture 11:00 o'clock every week or was it back to 9 next week? No, it's 11:00 o'clock. So what you've got on your? Timetable. So the 9:00 o'clock is a hangover from last year. So we had the online lab at 9:00 o'clock.
56:38
Then we had the online lecture at 11.
56:45
Clearly I'm not sitting in the office because it be hard for me to give this online lecture with students knocking in the door and with other people in the office chatting, you know, on the phone and. And the fact that I don't have a a camera that work doesn't help either. So I do this here.
57:02
And then I have to travel to Paisley to do the campus thing. So we'll finish this here. Now, jump on a train and I'll be on campus at 2:00. O'clock.
57:12
The 9:00 o'clock one.
57:17
Is where we can have a discussion about how we want to do it. So I'm aware that some people in lasers just put a a question in the chat about it, so it might be that some weeks would decide that we're going to do online. So we might do week about. No, this is for Paisley to be very clear. So for Linux, show speak to Henry. It's up to him who he wants to run it there but for Paisley.
57:45
You've got a timetable on campus and you got a timetabled online, we will only do one or the other. We won't do both. So the 9:00 o'clock or the 2:00 o'clock we will do the 9:00 or the two. We won't do both. But we always do the 11:00 o'clock.
58:02
You will have to come in for tests. Not surprisingly, and I do want you to start coming in and apart from anything else we've been told to get start coming in. But I am happy to negotiate and as I say, we might do week about I I'm not sure.
58:20
If we have an on campus.
58:23
Plus you have to be there. So for the Paisley students, I'll chat with you later and we can decide what we want to do.
58:32
Thank you. Was OK.
58:34
Was that OK for you as well, Lisa? Yeah.
58:40
Sargundeep make sure you're logged in using your UWS credentials, so that's your banner ID. If you don't do that, you won't be able to log in.
58:54
So again, all this information is on one note, so the group reports the class tests little man computer everything is there.
59:07
Now as a list there of the groups from last year, I've left up there just to see that once we have the group set up, I'll put them up here so that you know.
59:22
Yeah, I know that Lisa. And and part of the reason so Lisa saying it stays quite far away. So do I. And so I absolutely understand. And it takes me. I've got two more than a tour or travel through a 2 hour class. So yeah, I I feel your pain.
59:41
So we will talk about what we do for Paisley and but there will be sometimes where you have to come in.
59:51
OK. Are you all happy with that?
59:54
Any other questions just now?
59:57
Can I ask a quick question? I just didn't know yesterday and haven't got the full timetable yet, so you know how long it will take and feel the timetable comes up.
1:00:06
And if it hasn't come up today, it it will be there by tomorrow. It's usually overnight. It will depend when you enroll. So basically all the systems interconnect and once you're enrol it sort of works its way on. You'll learn about it, and here's called a batch system. So we run these things overnight or at different times, so it shouldn't be too long for it to come through.
1:00:29
If you know the modules that you've chosen, speak to your tutor. So what? What program are you on?
1:00:42
Just to computer networking. Computer networking. I think your class tutor is Duncan, but Is she?
1:00:50
don't quote me. Yeah. So speak to Duncan. He'll be able to tell you which classes Yeah.
1:00:55
you have, and you'll be able to get access to them even for they're not. Get on your timetable. Haven't said that it's Friday, so you'll have them for next weekend away. If you don't have them by Monday. Just not.
1:01:08
Immediately contact Duncan because you don't want to fall behind. Yeah, nobody's thanks. But any other questions?
1:01:19
Right. I'm acutely aware that I've been talking for a long time. I'm also aware that it's a long time to sit in front of your computer, so I would encourage you to get up.
1:01:30
Walk around, go a cup of tea, do anything else that you want to do. And. We'll have a second part to this where we'll do the introductory chapter. In 10 minutes time. So take a break and I'll see you in nine minutes and 55 seconds from now.
1:01:52
OK. Yes.
1:11:54
OK. And we're back.
1:11:58
But we took a week break, got something to drink.
1:12:04
Yep, Alice stopping away there. Excellent.
1:12:09
Isn't how long it takes to actually make a cup of tea.
1:12:13
OK so.
1:12:16
What we're gonna do is.
1:12:20
Do the introductory chapter from our book that you have already bought, I am sure.
1:12:33
There was one thing I forgot to say. In the first half I said that our labs, so on campus stuff for the first half will be on the little man computer for the second-half, it will be dedicated to the group report. So it will allow you to get together in your groups and work in your report. But we'll be there if you have questions or you need to help or whatever. So the first half sale, MC second-half of group report.
1:13:00
So that's it. I want to do the introductory chapter from the book. And one of the things I'll see is.
1:13:10
Remember said, I've cut down stuff and at and a half.
1:13:15
So there's our introductory chapter. And you'll see that there are two versions of the slides.
1:13:25
And I've cut down.
1:13:28
Quite a lot from this, and they're still 55 slides on it.
1:13:34
No, don't worry.
1:13:38
Part of the reason it's 55 slides is it's covering what we're going to do. So what I'm going to do is go through it. Give you an idea of what we're going to be doing, but I'm not going to go into any detail when anything until of course, that's what the subsequent chapters are doing. So this bet is just to give you an idea of what's coming up. So I'm not gonna go over and detail.
1:14:01
And stayed. It's gonna be about headings.
1:14:05
About what we're going to do about the fact that we're gonna look at how operating systems are are put together and all the different bits that we need to make up and operating system and to figure out. But it's definitely different operating systems. Why? Why is?
1:14:24
Why is a mic chosen a different file system to a Windows machine?
1:14:32
So we'll look at all that kind of stuff and of course, we'll start off by asking what actually is an operating system.
1:14:39
And the simple answer is it's the bet between the meat and the thing that does something useful.
1:14:47
So you want to.
1:14:50
If a PowerPoint presentation.
1:14:54
On my operating system, I have to find the presentation.
1:14:59
I have to use my mouse to point to it and I have to double click it. That then makes an association with the appropriate.
1:15:09
Executable, in this case PowerPoint, and it means that you see.
1:15:14
That slide up there.
1:15:19
I'm the guy at one end pressing a button, PowerPoints at the other end.
1:15:25
Showing you the presentation to band between, there's a whole lot of other stuff going on.
1:15:30
It has to know that I've moved the pointer on the screen and it has to update that it has to know when I click the button.
1:15:42
I click the button here, it goes to the next slide.
1:15:47
If I click the button on the PowerPoint file, or rather if I double click it, if I click it, it selects it. If I double click it, it runs it so it has to know the difference between that.
1:15:59
And then has to go and get the file, which in my machine is on an SSD.
1:16:06
So goes gets to fail. And it looks at it and it loads into working memory and it figures out what it is and it realises it's a PowerPoint fail. So it says. Ohh actually I've loaded the file but I need to load the program that runs it so it goes away to my SSD and brings back PowerPoint and loads that into working memory. And then it tells the display to update. With the PowerPoint interface.
1:16:34
On PowerPoint then uses the operating system to display all its buttons and menus and all the other stuff.
1:16:43
So the operating system is doing quite a lot.
1:16:48
It knows that the thing that I've called introduction to operating systems is located at file location 27856 on my SSD and not file location 1284 on my USB drive or a file location 261593 on my network storage.
1:17:12
So it's going to make all those connections as well.
1:17:15
So it's an awful lot going on there. It's got to know about the hardware.
1:17:21
The screen that I'm watching it on the CPU that's running the program that I owe devices like the mouse and the keyboard, the hardware the. I'll desk, although all those other bits and pieces.
1:17:35
Has to control all of those, and it has to control them. And my own case was just me, but some operating systems with more than one person using it, but I'm definitely using one more than one program.
1:17:48
And a host to know which bets.
1:17:52
Get preference. Which pets get to?
1:17:56
Use the helpdesk first. Which program is the most talking about? So as the sharer all those resources and to all those things that you run on your computer.
1:18:09
And it has to spread them not just between.
1:18:12
Those particular applications, but other people, or maybe even other computers.
1:18:18
Operating system has to take care of all of that.
1:18:24
So you might have multiple users using multiple applications. But they all controlled by the one operating system that. Uses the hardware, so the operating system also sits between you and the hardware.
1:18:41
Both to make sure that you don't mess up, but also to make sure that everything works together.
1:18:47
And you have to decide as part of your decision making about your operating system what you mean by working together and working well.
1:18:58
And that might mean different things for different. Types of system.
1:19:07
I've got a Linux box set up with hard disks that I run as a network storage device.
1:19:14
I'm not really bothered about it having a nice fancy graphical interface. In fact, I definitely don't want it to have a graphical interface because I don't want it wasting any resources creating a graphical interface and having a mouse. So instead I've got a command line interface where I type commands.
1:19:32
Over the network as it happened, so it's got network connections.
1:19:37
So it's not as easy to use because I have to type commands, but it's more. It it performs better, so those might be 2 competing demands that we have.
1:19:49
It might mean that it works out. The resources. And again, part of that is.
1:19:57
Well, the the type of interface, but it's also deciding on if I save to my network attached device which hard disk does it go to? Click it multiple ones in there. Does it go to more than one to automatically back up as I'm doing it?
1:20:14
And for some systems, and you're all logged into the university systems, it's got to do that for all the people that's on this call.
1:20:22
And it's got to assign all those resources between all the people that are on that call. And make sure that you're all seeing the the video and all hearing me properly and all seeing the slides.
1:20:34
So those are whole bunch of things that it's doing.
1:20:39
And there are competing ways that it might want to do them.
1:20:44
Whether it's a Windows machine. I wondered what station Windows Server.
1:20:50
My iPhone.
1:20:53
The computer that controls the ABS in my car. Because I was getting operating system as well.
1:21:00
And all of those things will have.
1:21:03
Different concerns and will concentrate on different things.
1:21:08
It will decide which resources things should have.
1:21:14
I'm quite glad that the ABS in my car.
1:21:19
Has its own computer and its own operating system because I don't want. The CEPS to also be running the same computer that runs the in car entertainment service.
1:21:31
Because I don't want resources taken away from the ABS.
1:21:35
To be checking what the NPC's called.
1:21:39
You're going to press the brake pedal and you get the operating systems in. Hang on. I'm just. I'm just contacting the CD database to find out what the name of this track is. I'll I'll put the brakes on shortly.
1:21:53
Not really a good idea.
1:21:56
So you want resources to be allocated and you want to be allocated in the best way possible for what you're doing.
1:22:05
I do not want a blue screen of death in my car because if it happens in my car, it could really be a blue screen of death when a buying into that wall.
1:22:15
So Master is set resources it has to control things.
1:22:21
And stop you doing stupid things.
1:22:25
Like Overrating one program with another overrating somebody else's data with something else.
1:22:32
So there is no such thing as the operating system. There's only. And operating system. This particular operating system that has this set of functions to do this set of tasks in this particular context.
1:22:50
So we'll look at what all those things are.
1:22:53
And we'll look at what controls them, which in this case is a kernel. So that's that's the core program for the operating system itself. The bet that you could see as the operating system any of you that have come across Linux. Actually, a Linux system means a Linux kernel. Most of the other stuff.
1:23:14
Is actually from other places like the Free Software Foundation or something like that. It's the kernel that's the core of the operating system, and it has to be tailored to the hardware, whether you're running it on a Mac or an iPhone or an Android tablet has to be tailored to that hardware.
1:23:36
How does this stuff happen? We all when you start up, you've probably seen your machine say things like. Checking what hardware we have. That's called Bootstrap and that's stored in a wee chip that you'll know about from last year called our food all the memory and it runs a small program and the small program says OK, I've got a display and I've got helpdesk and I've got keyboard and I've got a mouse.
1:24:02
Which actually is my favorite ever error message, and the LED's of. Windows machines. If you didn't have a keyboard attached, it would say keyboard error. Press F1 to continue.
1:24:16
And that's a genuine error.
1:24:20
So the bootstrap program runs, checks everything OK, checks you've got all your hardware and then transfers to some other device, typically a hard disk or an SSD or something in that starts up the operating system. And now operating system runs in the CPU and connects to all the stuff that you have already identified as part of your bootstrap. All of those hardware devices.
1:24:47
Then we have to make sure that they all work, so we have to have connections to all of those IO devices. In any of your other installed any new device on your machine, you've installed a new mouse or a printer. Won't know that you install a new program for it, and it's basically a way of saying to the operating system. Oh, here's a new printer. Here's what you need to tell it to make it print an A on the on the paper.
1:25:12
So all of these devices have their own programs that go with them that have some space to store data on. To be able to connect, send information from your version of word to the printer so that what you create on the screen gets to the paper.
1:25:31
All of these things have to be controlled, and clearly we can't do them. All at the same time. You should remember from last year that is CPU can only do one thing at a thing and you saw that in the LMC earlier. It's only doing one instruction.
1:25:46
One instruction.
1:25:49
So what happens if you want something to change? What happens if you are busy typing text into word and you get? Uh, a packet in from the network because you're getting a message.
1:26:03
Well, you have to stop what you're doing and do something else, and it's called an interrupt and we'll talk about how they work and how you move from one application. To another.
1:26:13
Although we would call them applications because they're processes.
1:26:18
Some of these things you don't even know are running. And we'll look at that as well and we'll look at different ways that we can do interrupts. We'll look at how long they take. What has to happen for these things too? And be useful so that our input output can all work. I mean, we'll look at the kinds of things that we have to set up for that to make that work.
1:26:49
We wouldn't be looking at these kinds of definitions because you'll know them from last year. You'll remember bits and kilobytes and megabytes and all that kind of stuff.
1:26:59
But we will be looking at different types of storage.
1:27:03
How they connect?
1:27:06
Why we have different types of stories that trade-offs that we make?
1:27:11
About how much something costs. So I'll get an SSD in my machine, but it was much more expensive than the. Helpdesk equivalent but on the other hand it's much faster.
1:27:25
And those kinds of trade-offs happen everywhere. Of course. Everybody wants the fastest, fastest CPU and the biggest storage and the largest display screen.
1:27:41
They all cost money.
1:27:43
So you make compromises and you decide what's more important.
1:27:49
If you do.
1:27:52
Design you may want a large high resolution screen cause that's important to you.
1:27:59
If you play games, you might want a fast CPU.
1:28:04
And you certainly want your iota be fast so that you don't miss a a trigger pull.
1:28:12
So we'll look at how these things happen and we'll look at ways of speeding up devices, using things like caching.
1:28:20
So that we can have a device going faster even when it's intrinsically slow. So we'll look at how all these things fit together, how they all connect, how information is sent from one to the other, how this caching can speed things up to make it appear that our devices are faster than they actually are. We'll look at other techniques for connecting devices like direct memory access.
1:28:46
To live is to transfer information, say from a hard disk to working storage.
1:28:54
Without having the CPU involved.
1:28:58
We'll look at all of these things, including.
1:29:03
How?
1:29:04
Computers work. At the basic level, and that's where the LMC comes in. And it's where what you spoke about and computer systems comes in. All of our modern computers follow something called a A von Neumann architecture.
1:29:22
Which is what you see on screen here.
1:29:27
You have a set of instructions. It won't its way through this set of instructions. Executing them until it's told to stop.
1:29:35
Again, that's exactly what we did. With that, we LMC program earlier, it had a set of instructions that had one after the other and then we told it to stop.
1:29:44
All of the computers that we use do exactly the same thing. They all working exactly that way that that LMC booked, the computer that you're looking at just now on the phone, that you're looking at just now or the tablet you're looking at just now works in exactly that way.
1:30:00
Ohh be it more instructions running more quickly.
1:30:06
So. We all have a processor that executes those instructions. Some of us, if we have more money, have multiple processors where we can have a CPU running one instruction and other CPU running another.
1:30:22
We might have them either cyber side, so get two separate CPU and we send it formation to CPU's. They make the burned up into one package, so we'll get CPUs with multiple cores so that we can run multiple things and get more. Things happening at once.
1:30:41
And the sorts of things that we can get happening are. Increased throughput economy of scale, increased reliability and you may be wondering why I'm reading these out.
1:30:52
I'm reading these things out because on these slides there in blue. Blue is your hint.
1:30:59
It's your hunt that that's the sort of thing that can be asked as a question.
1:31:05
Like.
1:31:07
Name something that a multiprocessor allows you. Would it be a?
1:31:16
A different color of computer BA bigger screen C, increased throughput D all of the above.
1:31:26
When you see blue, remember them, they're important.
1:31:33
So we might have multiple processors, each with their registers, each with their own cache. What registers? So that's that thing you saw at the CPU. Local memory storage lately accumulator and again stuff the issued. Remember from last year.
1:31:48
So it may be separate CPUs, it might be one CPU with multiple cores. We might have clustered systems where we have. Lots of physical computers all working together, and you might see that where you have, say, a a movie studio doing some. Graphics.
1:32:08
One dinosaur, maybe animated by one machine, another by another. A tree might be taken by a third machine, a Bush by a fourth. So you send them all out, they get processed and then they will come back to the center.
1:32:25
So you have shared storage, but each computer is connected and runs particular processes on that information.
1:32:36
We could have. Systems where we run.
1:32:42
Pure says he's one after the other, where we don't have any input at all.
1:32:48
We're talking earlier about enrollment, so we've got systems at the university that don't require any input but at say, 10:00 o'clock tonight, we'll look at the enrolled students and we'll create a timetable for them, buy at 10:00 o'clock at night, because we're not doing anything else with the computers at 10:00 o'clock at night. So it makes use of scarce resources. So rather than doing it at. 3:00 o'clock in the afternoon, when everybody's on the
1:33:14
computer, it doesn't 10 at night when nobody else.
1:33:17
So we'll use batch systems to run things later on. Or we'll use time sharing systems, which is what we are doing now on teams. We've got one central server.
1:33:29
And everybody on here gets some time on it to see whether you've typed something in or put your hand up or whatever it is you're happening to do.
1:33:38
So we'll look at those different types of system, how we set up the memory for them. How the end drops work for them and whether we use hardware or software for speed, how we protect all the information in there? How do we stop one? Program or one user overwriting another program or another user.
1:34:04
I will figure out who gets priority.
1:34:09
How we stop one person or one process using all of the resources of the computer? You've all seen that you'll all have pressed a button at some time and your computer feels if it's stopped, might just be loading up your gram or something. You can't do anything else.
1:34:28
How do we cut down and how that feels? In other words, how do we manage all those processes, all those executing pure successes that we have in our computer? How do we give them enough CPU? Enough memory enough access to all of our IO devices? How do we make them all work together?
1:34:46
With one CPU executing one instruction. How do we make them all work together to make it feel as if?
1:34:54
Teams is working at the same time as PowerPoint is working and is running at the same time as OneNote is working. How do we manage that?
1:35:06
I would have been make it so that all these things synchronise.
1:35:10
How do we send information from one to another?
1:35:17
I'm just me clicking on a.
1:35:22
Meeting an outlook start teams.
1:35:26
How does all that stuff work? How do we communicate? How do we get information from one to the other? How once we have all those things loaded, do we put them all into memory and not have them all crashed together?
1:35:40
How do we keep them all separate and make sure process one sticks to where it's supposed to be in process? Two sticks to where it's supposed to be an Allen sticks to where he's supposed to be in Liam sticks to where he's supposed to be.
1:35:52
How do we keep all these things apart? And stop them messing up other people or other people's data.
1:36:01
How do we keep all the stuff on our devices? Are hard disks or SSD or USB? How do we know that introduction dot PPT is stored at sector 57 on my SSD? What keeps that link? Well, clearly the operating system or I wouldn't be talking about it, but how does it do it in other are different ways that we can manage that.
1:36:27
And how do we manage that? How do we decide how we do that?
1:36:32
How fast will it be to keep it on different devices? Is it better for me to keep my file? Ohh and hard disk on an SSD and USB or a network drive. And how do we get it from one place to another? How do we get?
1:36:50
Just like we did with the LMC this morning. How do we get an instruction from the hard disk into main memory and running on CPU hardware register?
1:37:00
How do we even connect that hardware in the first place?
1:37:06
How do we get those onto our computer and make sure that they all work? And that we can have. Multiple hard disks or USB drives on network storage and we don't have to care.
1:37:18
We don't care whether we'll save in a fail or into a hard disk or an SSD. We just say save the fail.
1:37:24
Operating system sorts out and also sorts out whether you can access it or not. Whether you can get access to that OneNote, which is stored on a network server on Myspace on that network server and owned by me, but you're allowed to look at it. Something has to say that you're allowed to look at it, and that's the operating system.
1:37:47
Of course, that's. On my server, my part of the server and you're on your machine. So we have to be able to connect computers as well. So how does the operating system cope with all these networks and how does it know where to send the data and how to do that?
1:38:06
And that's without even thinking that you could be on a mobile device.
1:38:11
Never mind one that's connected to a wire.
1:38:14
So what are all those different types of network? And how do we send data from one to the other?
1:38:21
Is it going to be?
1:38:24
Smart computers are going to be clients. Is it going to be?
1:38:28
Smartphones.
1:38:31
How do we send data? Is something in charge or do we spread about amongst lots of places?
1:38:40
And if for example we want to run multiple things on one device, can we virtualize and can we put our Unix operating system on a Windows machine? Well yes we can because we can use virtualization.
1:38:54
And if we have an old machine that was installed in 1995, but it runs software and it's important to your.
1:39:03
Company can we virtualize that machine and run it on a new machine? Will yes, you can. And IBM make billions of dollars a year doing exactly that. The virtualized environments, instead of having physical machines.
1:39:19
And sometimes you don't even need to have a box in your office. Sometimes you can just have a connection to a cloud machine.
1:39:29
That's running somewhere that you don't care about. And backed up by somebody that you don't know about.
1:39:38
Sometimes you don't even know the operating system exists because it's running in real time on your car.
1:39:46
Or on your.
1:39:48
Ring doorbell or on a nuclear power station.
1:39:57
And either case you want something to happen in real time. I want my brakes to come on. I want my doorbell to note that somebody's there.
1:40:07
I want the nuclear power station to not overheat and go bang. So, Tina, what not to happen, the exactly the right time.
1:40:16
And of course, there's lots of different types of operating systems from different companies, and there's also open source ones that use all sorts of other.
1:40:25
OK. Resources to create them. So we'll be covering all of that. So that was the very quick short through what we will be doing, 55 slides and 12 minutes. That's quite impressive. I have to say.
1:40:42
So you can look at that and and detail. It will be covering all of that over the next few weeks. Thank you for the applause. That's very kind.
1:40:51
Any questions about that?
1:40:56
Not at all.
1:40:58
Why is usual? That's on. I've lost my mouse there is. That's when chapter one and that presentation that we just looked at there isn't there. And the original presentation from the book is there. So it's gonna be a bit more in it.
1:41:18
Now one of the things I didn't mention when I talked about the chapter tests is we also have. Chapter tutorials.
1:41:29
So every chapter has a chapter tutorial.
1:41:36
It's a quiz.
1:41:39
Distinguished between client, server and peer-to-peer models of distributed systems.
1:41:46
So every week I want you to complete these chapter tutorials and these Charter tests and hand them in and I will be keeping an eye on whether you've done them.
1:41:59
I'm not going to mark them.
1:42:02
Because I want you to be responsible for your learning.
1:42:06
So if you're not passing the chapter test, absolutely ask me if there's something that you don't understand, but it's up to you to keep studying till you can pass. Yes, I will help absolutely, I will help. That's what I'm here for. But I need you to do your part as well. Similarly with these tutorials.
1:42:24
I won't be marking them as such, but if you go through them.
1:42:30
And you know you can't find the answer to a question 4 then ask, but only after you've tried to do it yourself.
1:42:39
OK, so there are chapter tutorials. And IT chapter reviews on chapter tests for all of the chapters. So you're part of what you would do in the lab is that?
1:42:55
And following weeks and I certainly won't be speaking for two hours. So you can do it as part of this one as well, so. With what cover some of the material and then you can do the tests.
1:43:13
Any questions?
1:43:18
Hey I'm not seeing anything, so let me stop the recording.
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