Operating Systems 03

21. Resources are allocated to the process on non-shareable basis is

[Paper II June 2012]

(A) mutual exclusion

(B) hold and wait

(C) no pre-emption

(D) circular wait

22. Cached and interleaved memories are ways of speeding up memory access between CPU’s and slower RAM. Which memory models are best suited (i.e. improves the performance most) for which programs?     [Paper II June 2012]

(i) Cached memory is best suited for small loops.

(ii) Interleaved memory is best suited for small loops

(iii) Interleaved memory is best suited for large sequential code.

(iv) Cached memory is best suited for large sequential code.

(A) (i) and (ii) are true.

(B) (i) and (iii) are true.

(C) (iv) and (ii) are true.

(D) (iv) and (iii) are true.

23. Consider the following page trace: 4,3, 2, 1, 4, 3, 5, 4, 3, 2, 1, 5

Percentage of page fault that would occur if FIFO page replacement algorithm is used with number of frames for the JOB m = 4 will be                       [Paper II June 2012]

(A) 8                (B) 9

(C) 10             (D) 12

24. Given memory partitions of 100 K, 500 K, 200 K, 300 K and 600 K (in order) and processes of 212 K, 417 K, 112 K, and 426 K (in order), using the first-fit algorithm, in which partition would the process requiring 426 K be placed ?                  [Paper II December 2012]

(A) 500 K

(B) 200 K

(C) 300 K

(D) 600 K

25. The problem of indefinite blockage of low-priority jobs in general priority scheduling algorithm can be solved using:   [Paper II December 2012]

(A) Parity bit

(B) Aging

(C) Compaction

(D) Timer

26. Which of the following memory allocation scheme suffers from external fragmentation?

[Paper II December 2012]

(A) Segmentation

(B) Pure demand paging

(C) Swapping

(D) Paging

27. In UNIX, which of the following command is used to set the task priority?      

[Paper II December 2012]

(A) init

(B) nice

(C) kill

(D) PS

SOLUTIONS

21. A

22.

23. C
The first 4 page references will cause page faults and they are brought into the 4 page frames available. The sequence is shown below
4 - page fault, brought to frame. Page Frame : 4
3 - page fault, brought to frame. Page Frame : 4, 3
2 - page fault, brought to frame. Page Frame : 4, 3, 2
1 - page fault, brought to frame. Page Frame : 4, 3, 2, 1
4 - available in the frame, no page fault occurs. Page Frame : 4, 3, 2, 1
3 - available in the page frame, no page fault occurs. Page Frame : 4, 3, 2, 1
When the fame is full and a page fault occurs, then the page that was first brought in is removed and the referred page is brought in to the frame.
5 - not in the page frame, page fault. 4 is removed and 5 is brought is. Page Frame : 5, 3, 2, 1
4 - not in the page frame, page fault. 3 is removed and 4 is brought is. Page Frame : 5, 4, 2, 1
3 - not in the page frame, page fault. 2 is removed and 3 is brought is. Page Frame : 5, 4, 3, 1
2 - not in the page frame, page fault. 1 is removed and 2 is brought is. Page Frame : 5, 4, 3, 2
1 - not in the page frame, page fault. 5 is removed and 1 is brought is. Page Frame : 1, 4, 3, 2
5 - not in the page frame, page fault. 4 is removed and 5 is brought is. Page Frame : 1, 5, 3, 2

24. A
100 K, 500 K, 200 K, 300 K and 600 K (in order) and processes of 212 K, 417 K, 112 K, and 426 K
According the to the first fit algorithm, the memmory will be scanned to find out the memory portion that is enough for the arriving process, The first such portion found is allocated to the process. In the given example when process of size 212K arrives it is placed in memory portion with size 500K. This leaves an unused space of 288K. Now 417K arrioves it is placed inportion with size 600K, leaving 183K unused. Now 112K arrives and this can be placed in the un used sopace of 183K. Atlast the process of 426K arrives, we dont have memory block large enough to hold this, so we need to remove some already allocated process and allocate that block. 500k block is the one suitable if we do a linear search.
25. B

26. A

27. B
init - Init is the parent of all processes. Its primary role is to create processes from a script stored in the file
nice - run a program with modified scheduling priority
kill - terminate a process

ps - report process status

Web 01

01. Match the following with respect to HTML tags and usage          [Paper III December 2012]

a. CITE                       1.Italic representation

b. EM                          2.Represents output from programmes

c. VAR                        3.Represents to other source

d. SAMP                     4.Argument to a programme

Codes :

A         b          c          d

(A)       3          1          4          2

(B)       2          3          1          4

(C)       4          2          3          1

(D)       1          3          4          1

02. Which one is a collection of templates and rules?     [Paper III December 2012]

(A) XML

(B) CSS

(C) DHTML

(D) XSL

03. Which is the method used to retrieve the current state of a check box?

[Paper III December 2012]

(A) get State ( )

(B) put State ( )

(C) retrieve State ( )

(D) write State ( )

04. BCC in the internet refers to             [Paper II December 2011]

(A) Black carbon copy

(B) Blind carbon copy

(C) Blank carbon copy

(D) Beautiful carbon copy

05. Data security threats include           [Paper II December 2011]

(A) privacy invasion

(B) hardware failure

(C) fraudulent manipulation of data

(D) encryption and decryption

06. HTML is defined using SGML – an _______ standard, information processing-text and office systems (SGML) for text information processing.           [Paper III June 2012]

(A) ISO – 8878

(B) ISO – 8879

(C) ISO – 8880

(D) ISO – 8881

SOLUTIONS

1. A

The <cite> tag defines the title of a work (e.g. a book, a song, a movie, a TV show, a painting, etc.).

The <em> tag is a phrase tag. It renders as emphasized text.

The <var> tag is a phrase tag. It defines a variable.

The HTML <samp> tag is used for indicating sample output from a computer program, script etc.

2. D

Extensible Markup Language (XML) is a markup language that defines a set of rules for encoding documents in a format that is both human-readable and machine-readable.

Cascading Style Sheets (CSS) is a style sheet language used for describing the presentation semantics (the look and formatting) of a document written in a markup language.

Dynamic HTML, or DHTML, is an umbrella term for a collection of technologies used together to create interactive and animated web sites by using a combination of a static markup language (such as HTML), a client-side scripting language (such as JavaScript), a presentation definition language (such as CSS), and the Document Object Model.

Extensible Stylesheet Language (XSL) is used to refer to a family of languages used to transform and render XML documents. XSL consists of three parts:

• XSLT - a language for transforming XML documents
• XPath - a language for navigating in XML documents
• XSL-FO - a language for formatting XML documents

3. A

4. B

5.

6. B

ISO – 8878: Telecommunications and information exchange between systems. Use of X.25 to provide the OSI connection-mode network service.

ISO – 8879: Information processing -- Text and office systems -- Standard Generalized Markup Language (SGML)

ISO – 8880: Information technology -- Telecommunications and information exchange between systems -- Protocol combinations to provide and support the OSI Network Service

ISO – 8881: Information processing systems -- Data communications -- Use of the X.25 packet level protocol in local area networks