CE Operating Systems Lecture 22 Operating Systems - Revision Lecture

Overview of lecture In this lecture we will look at: Procedure Format of test Learning outcomes & implications for test Approach to revision/preparation Advice over answering questions

Procedure Thursday 3pm 22nd November Blue Lecture Theatre– be on time – it will start as soon as I finish handing out the papers and I will arrive a few minutes before 3pm to start handing out 50 minutes long Given paper and pink booklets Put name details in fold down corner and module details and id on front

Format of test 2 questions – both compulsory One worth 50 marks, the other 20 marks – so make sure you apportion your time between questions appropriately

Relevant learning outcomes In the module specification the learning outcomes that are associated with the class test are specified as, 1. Explain and evaluate the operation of the internal algorithms and structures of a modern multi-user/multi-tasking operating 2. Critically compare and evaluate the operation of a number of different example operating systems.

Implications from learning outcomes The learning outcomes should give you a good clue as to the areas that you should focus your revision on i.e. the class test will focus on the comparison between example operating systems and the internal structures and algorithms by which they function. That means for you on the comparison of Windows and Linux/Unix

Implications from learning outcomes (Cont.) You need to revise generally about operating systems in order to understand better the examples drawn from Windows and Linux Identify the lectures (and parts of lectures) that cover Linux/Unix and Windows as examples You need then to focus your revision on those lectures and parts of lectures where Windows/Linux are used as examples

What to revise Make sure you understand how Windows and how Unix/Linux handle various OS activities. However, you will also need when revising to think about the comparison between them i.e. strengths/weaknesses, advantages & disadvantages, differences and similarities of the different approaches You will need to think about this as you revise the various different topics

What to revise (Cont.) Other than telling you to focus on Windows & Unix/Linux – there are no other clues in this lecture – so revise everything we have covered on Windows & Linux/Unix There will be no programming exercises in the test, so only look at the practical exercises to help you understand something we covered in the lectures

Types of question Think about the learning outcomes – the questions will require you to explain about how Windows manages some OS function and then how Unix/Linux manages the same OS function and then about how they compare – advantages/disadvantages, highlighting the differences or similarities, etc.

How to revise Just some advice: Imagine that you had to write some exam questions When reading the notes, think about how you might construct an exam question for the subject you are revising. You can even try answering your own questions Try out the example test

Answering questions You can draw diagrams where appropriate, but please don’t waste time doing beautiful drawings, you can simply sketching by hand what you need to.

Lectures to be covered Lectures in which I have covered aspects of Windows/Linux that might be tested are: Lecture 4 – Windows overview Lecture 6 – Linux/Unix overview Lecture 10 – Linux processes & threads Lecture 11 – Windows – Object oriented approach & threads/processes Lecture 13 – Linux/Unix interprocess communication

Lecture 16 – Windows & Linux virtual memory management Lecture 18 – Windows File System Lecture 19 – Linux/Unix file system Lecture 21 – Windows & Linux protection mechanisms

Question from example test 1. Explain the mechanisms involved in mapping between logical (within file) location and disk (physical) locations in, a) Windows XP. In particular your discussion should include logical and virtual cluster numbers, the Master File Table, file and directory entries. (30 marks) b) Linux. In particular your discussion should include directory files and directory entries, i-nodes and the operation of i-node tables. (30 marks)

c) Identify areas of similarity and difference between the approaches of Windows and Linux. (20 marks) Note – question 1 in the example test is 80 marks, but in actual test it will be 50 marks i.e. I have made the test a little shorter than last time

Look at what is asked for I might, as in question above, give a list of topic areas drawn from the lecture notes which your answer should cover Use this as a guide – the marking scheme will have marks associated with each topic area So the questions will require you to explain how Windows does something, how Linux/Unix does something and to compare the 2 approaches

GOOD LUCK