Quiz 11.2

DIRECTIONS: Read each question carefully. Then click on the dot next to the answer that most closely fits the question. Try to answer all questions on this quiz and when you are done, click on the grade me button at the bottom.

Coverage: Sections 11.3 and 11.4

  1. Which type of address would an assembler programmer put in relocatable code?
virtual address
real address

  1. Who is generally credited with inventing the stored program concept?
Charles Babbage
Alan Turing
John von Neumann
John Backus

  1. What is the stored program concept?
programs should be stored in main memory while they are being executed since that is the fastest place to access them
programs are just sets of data and can be put in the same memory as data
programs and data are two completely different kinds of entities and should be stored in separate regions of memory

  1. What do we call chunks of memory into which a program or data is broken?
blocks
regions
slots
pages

  1. Which method is used today when a program has to move around in memory while it is running?
all addresses are rewritten by a special piece of operating system code
all addresses found in programs are added to the contents of a base address register
programs aren't moved around in memory any more
programs are kept in separate memory areas and each one begins with 0 so there is no need to change the addresses

  1. Modern compilers and linkers generate machine code that starts at ...
0
a user-defined address
the beginning of a region
any random address since it will have to be modified at run-time anyway

  1. What is the downside of using base+offset addressing for run-time relocation?
it makes the operating system too complicated
it slows down the computer
it requires extra Boolean logic to implement
it makes assembler programs harder for humans to write

  1. What is overhead?
a measure of the inefficiency in a system
all the extra system utilities and programs that people have to use to compile and link their programs
the extra Boolean logic that is required by the adders in the memory
an increment in resources required by a more complex system to do the same task as a simpler system

  1. If a CSC-1 program completes in 10 seconds and the same program on another computer takes 15 seconds, what would the slowdown be?
25%
50%
100%
150%

  1. Why do we willingly sacrifice machine cycles to the operating system, which does not do any useful user work?
because it permits things to be done which couldn't be done otherwise
because we want to keep Bill Gates and other OS makers happy and rich
because there is so much power and speed in modern computers that we don't care
because the operating system actually makes the hardware run faster

  1. What is the typical overhead of some modern operating systems?
much less than 5%
very high, about 90% or higher
mid-range, but shockingly high like 50% to 75%