1.(a)
(i) Define
throughput in the context of operating systems.
(ii) Name
one computing environment that typically desires a high throughput.
(iii) Discuss
the relation between process preemption and system throughput.
(b)
Shortest Job First (SJF) is a relatively simple
CPU scheduling algorithm. Consider that
there are two busy multi-programming systems A and B.
The new processes created on System A are mostly
long CPU burst processes with only occasional short CPU burst processes. The new processes created on System B are
mostly very short CPU burst processes.
State whether
process starvation is likely to occur on either or both System A and System
B. If process starvation occurs on
System A, explain which type of processes is likely to be starved. Similarly, if process starvation occurs on
System B, explain which type of processes is likely to be starved. Your answer should refer to relevant
characteristics of SJF.
2.
(a) Consider a paging system with page size of 32
bytes. The main memory size is 1024
bytes. Answer the following questions.
(i) Write down the frame size.
(ii) Calculate the number of frames in
the system.
(iii) Given the following page table of a
process in the paging system. Convert
the logical address 42 of that process into its corresponding physical address.
|
Page
|
Frame
|
Page
|
Frame
|
|
0
|
1
|
3
|
8
|
|
1
|
3
|
4
|
5
|
|
2
|
0
|
5
|
2
|
(v) Dynamic loading is a technique for faster
program startup and reducing use of main memory. Comment if dynamic loading can be
implemented in a paging system.
(b) Consider the following
Resource Allocation Graph (RAG) about a computer system. Comment on the possibility of
deadlock.
(c)
Translation look-aside
buffer (TLB) is a component for speeding up page table lookup. Assume that the TLB access time is 10 ns, the
original main memory access time is 60 ns.
If the TLB hit rate is 0.95, calculate the effective memory
access time (EMAT).
Extract from COMPS267F
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