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04 - Virtual Memory

 1. What is virtual memory?

  A memory management technique that creates the illusion of a very large (main) memory

  Long-term memory

  Large secondary memory

  Process for encoding information

 2. Where is data stored when it is in virtual memory?
vm1.png

  An optical drive e.g. CD

  A secondary storage device e.g. hard disk drive

  ROM

  RAM

 3. When several programs run at the same time, the RAM can be full. Instead of closing programs, the operating system uses virtual memory to store some data.

  False

  True

 4. Read/Write speed of a hard disk drive is faster than RAM.
vm2.jpg

  TRUE

  FALSE

 5. Fill in the blanks.
Because of virtual memory, the memory can be shared 
among___________________.

  none of the mentioned

  threads

  processes

  instructions

 6. Hard drive failure rates are measured with MTBF (Mean Time Between Failures). Which of these failures would be reason to replace your current hard disk?

  Application removal

  File delete

  Head crash

  Can't read CDs

 7. Fill in the blanks.
A virtual memory block is known as page, and a virtual-memory miss is 
called a________________.

  hit miss

  memory fault

  page miss

  page fault

 8. Effective access time is directly proportional to:

  memory access time

  hit ratio

  page-fault rate

  none of these mentioned

 9. Virtual memory frees applications from managing shared memory and saves users from adding more memory modules when RAM space runs out.
vm3.jpg

  FALSE

  TRUE

 10. Fill in the blanks.
The address location in the main memory, is referred to 
as____________________.

  static address

  logical address

  block associative

  physical address

 11. A process is thrashing if:

  it is spending less time paging than executing

  it is spending more time paging than executing

   page fault occurs

   swapping cannot take place

 12. Fill in the blanks.
Virtual memory is normally implemented by ______________.

  buses

  virtualization

  demand paging

  all of the mentioned

 13. The use of virtual memory slows a computer because data must be mapped between virtual and physical memory, which requires extra hardware support for address translations.

  TRUE

  FALSE

 14. The first hard disks, created in the 1950s, could be up to 20 inches in diameter. Which company invented the hard disk?
vm4.jpg

  HP

  Xerox

  Intel

  IBM

 15. When purchasing a hard disk which of these is generally NOT a specification that would be of concern?

  seek time

  capacity

  data rate

  mounting holes