eecs3221

Student Name:_____SOLUTION_____________________________ Student ID:____________________


LE/EECS 3221 – Operating System Fundamentals
Fall 2019 – Section A

Midterm Exam (October 29, 2019)


Duration: 120 Minutes Start Time: 19:15

This examination paper includes 6 pages (including this cover page and printed both sides).
Please count the pages and inform the invigilator immediately if there is an issue. There




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are 39 questions in the exam.




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Please read the following instructions carefully:
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Write your name and/or ID on each page of this exam booklet.
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You must answer on the answer booklet provided to you.
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• You must return the exam booklet with the answer booklet.
• Use of any calculator is allowed. Sharing is not permitted. Phone calculators are not
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permitted.
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• Please write clearly.
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• Try to answer as briefly as possible.
• If you have confusion regarding any question statement, write your assumptions and
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answer accordingly. Make sure your assumptions are logically correct.
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Section Total Score Student Score
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A 14

B 20

C 20

Total 54




Winter 2019 LE/EECS 3221
https://www.coursehero.com/file/74272162/EECS-3221-F19-MainM-Solutionpdf/
1

, Student Name:_____SOLUTION_____________________________ Student ID:____________________


Section A

1. What is the purpose of strace utility? [1 Mark]
It traces system calls invoked by a process
2. Name different segments of memory area allocated to a process. Also mention their purpose.
[2 Marks]
Text section: contains program code
Stack: containing temporary data such as function parameters, return addresses, local variables
Data section containing global variables
Heap containing memory dynamically allocated during run time




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(0.25 per name, 0.25 per description [ignore minor issues in description])




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3. When context switching happens, what is the most important information that must be updated in the




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PCB of outgoing process so that it’s execution can be successfully resumed later? Mention at least two




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items.
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Program Counter, Registers, Memory Limits, Open Files [Any two is correct, 0.5 per item]
4. Describe cascading termination. [1 Mark]
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If a process terminates, all of its children processes will be terminated. [Don’t look for precise
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wording]
5. If a process has multiple threads, can we execute those threads in parallel on a single processor single
core system? [1 Mark]
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No
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6. Describe Data Parallelism with the help of an example. [1 Mark]
Distribute subsets of the same data across multiple cores/CPUs/machines/processors, to
perform same operation on each such task [0.5 mark]
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For example, to search k in a huge list, a portion of list is passed to each
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core/CPU/machine/processor so that it can search k in that portion [0.5 mark; other examples
with similar sense are possible]
7. How different threads of the same process can communicate with each other inside the process space?
Mention at least one mechanism. [1 Mark]
Shared or global variables (1 mark) or Files(0.5)
8. Name the two approaches used for Thread cancellation. [1 Mark]
Deferred, Asynchronous (0.5 per item)
9. What is the purpose of clone() system call? [1 Mark]
Creates a thread or child task



Winter 2019 LE/EECS 3221
https://www.coursehero.com/file/74272162/EECS-3221-F19-MainM-Solutionpdf/
2