Deck 8: Virtual Memory

Question 1

The addresses a program may use to reference memory are distinguished from the addresses the memory system uses to identify physical storage sites.

Answer 1

True

Question 2

One way to counter the potential performance problems of a variable-allocation global scope policy is to use page buffering.

Answer 2

True

Question 3

Segmentation is not visible to the programmer.

Answer 3

False

Question 4

Segments may be of unequal, indeed dynamic, size.

Question 5

_________ is the virtual storage assigned to a process.

A) Virtual address space
B) Virtual address
C) Real address
D) Address space

Question 6

The PFF policy evaluates the working set of a process at sampling instances based on elapsed virtual time.

Question 7

The size of virtual storage is limited by the actual number of main storage locations.

Question 8

Most of the memory management issues confronting the operating system designer are in the area of paging when segmentation is combined with paging.

Question 9

The __________ structure indexes page table entries by frame number rather than by virtual page number.

A) hash table
B) segment table
C) page table
D) inverted page table

Question 10

The smaller the page size, the greater the amount of internal fragmentation.

Question 11

Virtual memory allows for very effective multiprogramming and relieves the user of the unnecessarily tight constraints of main memory.

Question 12

__________ is the range of memory addresses available to a process.

A) Address space
B) Real address
C) Virtual address
D) Virtual address space

Question 13

The design issue of page size is related to the size of physical main memory and program size.

Question 14

The address of a storage location in main memory is the __________ .

A) address space
B) virtual address space
C) real address
D) virtual address

Question 15

The principle of locality states that program and data references within a process do not tend to cluster.

Question 16

The placement policy determines where in real memory a process piece is to reside.

Question 17

The _________ states the process that owns the page.

A) process identifier
B) control bits
C) page number
D) chain pointer

Question 18

The page currently stored in a frame may still be replaced even when the page is locked.

Question 19

UNIX is intended to be machine independent; therefore its memory management scheme will vary from one system to the next.

Question 20

A precleaning policy writes modified pages before their page frames are needed so that pages can be written out in batches.

Question 21

The _________ determines when a page should be brought into main memory.

A) page fault
B) fetch policy
C) working set
D) resident set management

Question 22

The portion of a process that is actually in main memory at any time is defined to be the _________ of the process.

Question 23

A _________ chooses only among the resident pages of the process that generated the page fault in selecting a page to replace.

A) global replacement policy
B) page replacement policy
C) local replacement policy
D) page placement policy

Question 24

_________ is the concept associated with determining the number of processes that will be resident in main memory.

A) Virtual memory manager
B) Page fault frequency
C) LRU policy
D) Load Control

Question 25

The __________ policy treats the page frames allocated to a process as a circular buffer and pages are removed in round robin style.

Question 26

The size of virtual storage is limited by the addressing scheme of the computer system and by the amount of __________ available.

Question 27

The technique where the processor is equipped with hardware that allows it to interrogate simultaneously a number of TLB entries to determine if there is a match on page number is referred to as __________ .

Question 28

To overcome the problem of doubling the memory access time, most virtual memory schemes make use of a special high-speed cache for page table entries called a __________ .

Question 29

__________ is transparent to the programmer and eliminates external fragmentation providing efficient use of main memory.

A) Hashing
B) Paging
C) Segmentation
D) Thrashing

Question 30

With _________ pages other than the one demanded by a page fault are brought in.

A) slab allocation
B) thrashing
C) hashing
D) prepaging

Question 31

A __________ policy allows the number of page frames allocated to a process to be varied over the lifetime of the process.

Question 32

The _________ algorithm requires a use bit to be associated with each page in memory.

A) page placement
B) working set
C) VSWS
D) page fault frequency

Question 33

When the system spends most of its time swapping pieces rather than executing instructions it leads to a condition known as _________ .

Question 34

The _________ policy results in the fewest number of page faults.

A) Optimal
B) FIFO
C) Clock
D) LRU

Question 35

_________ is where modified process pages can be written out at the time of replacement, or a precleaning policy can be used, which clusters the output activity by writing out a number of pages at once.

A) Load control
B) Cleaning policy
C) Placement policy
D) Replacement policy

Question 36

The address assigned to a location in virtual memory to allow that location to be accessed as though it were part of main memory is the __________ .

Question 37

_________ allows the programmer to view memory as consisting of multiple address spaces.

A) Paging
B) Locality
C) Segmentation
D) Resident set management

Question 38

_________ is a storage allocation scheme in which secondary memory can be addressed as though it were part of main memory.

Question 39

Because a process executes only in main memory, that memory is referred to as ____________ .

Question 40

A _________ is issued if a desired page is not in main memory.

A) paging error
B) page replacement policy
C) page fault
D) page placement policy

Question 41

In SVR4 and Solaris systems, the memory management scheme that manages memory allocation for the kernel is called the _________ .

Question 42

Linux makes use of a three-level page table structure consisting of the following types of tables: page directory, page table, and __________ .

Question 43

The __________ provides a virtual memory capability that allocates page frames in main memory to processes and also allocates page frames to disk block buffers.

Question 44

The __________ policy replaces the page in memory that has not been referenced for the longest time.

Question 45

With __________ , a page is brought into main memory only when a reference is made to a location on that page.