ITS-235 Quiz 3
fault
A page __________ is a type of hardware interrupt caused by a reference to a page not residing in memory with the effect of moving a page out of main memory and into secondary storage so another page can be moved into memory.
page
A(n) _____________ refers to a fixed-size section of a user's job that corresponds in size to page frames in main memory.
Page Map Table (PMT)
A(n) _________________ refers to a table in main memory with the vital information for each page including the page number and its corresponding page frame memory address.
b. external fragmentation
A disadvantage of segmented memory allocation is ____. a. the physical size requirements of main memory b. external fragmentation c. the number of page faults d. internal fragmentation
a. swapped
In demand paging, pages are ____ between main memory and secondary storage. a. swapped b. traded c. allocated d. faulted
True
The Job Table (JT) contains two values for each active job: the size of the job and the memory location where its Page Map Table is stored. True/False
first-in first-out (FIFO)
The _________________ policy is a page replacement policy that removes from main memory that were brought in first.
True
In the bit-shifting variation of the LRU page replacement policy, the process of shifting bits to the right and resetting the leftmost bit to 1 when a page is referenced gives a history of each page's usage. True/False
b. the segment number and the displacement
To access a location in memory when using segmented memory management, the address is composed of two entries: ____. a. the line number and the displacement b. the segment number and the displacement c. the segment number, the line number, and the displacement d. the segment number and the line number
False
With segmented memory allocation, each job is divided into several segments of the same size, one for each module containing pieces that perform related functions. True/False
a. Cache memory
____ can be thought of as being an intermediary between main memory and the special-purpose registers, which are the domain of the CPU. a. Cache memory b. Segmenting c. Paging d. Virtual memory
d. Virtual memory
____ effectively removes restrictions on maximum program size. a. Shared memory b. Segmenting c. Multithreading d. Virtual memory
Cache
______________ memory is a small, fast memory used to hold selected data and to provide faster access than would otherwise be possible.
Associative
______________ memory is the name given to several registers, allocated to each active process, contents associate several of the process segments and page numbers with their main memory addresses.
d. bookmark file
The purpose of cache memory is to keep handy the most recently accessed data and instructions so that the CPU can access them repeatedly without wasting time. This purpose is similar to that of the ____ of a Web browser. a. block file b. page file c. cache file d. bookmark file
False
With demand paging, if there are no empty page frames available, to move in a new page, one of the current resident pages must be placed into main memory. True/False
False
A job's working set is the collection of pages that must be loaded from secondary storage. True/False
demand
A memory allocation scheme that loads a program's page into memory best describes __________.
False
Cache memory is based on the concept of using a large, fast, and expensive memory to supplement the workings of main memory. True/False
reentrant
Code that can be used by two or more processes at the same time such that each shares the executable code but has separate data areas best defines ___________ code.
True
Demand paging introduced the concept of loading only a part of the program into memory for processing. True/False
a. very long Page Map Tables
In a paged memory allocation scheme, a page size that is too small will generate ____. a. very long Page Map Tables b. excessive internal fragmentation c. excessive external fragmentation d. excessive page faults
b. Memory Map Table
In a paged memory allocation scheme, a simple ____ has one entry for each page frame that shows its location and its free/busy status. a. Page Access Table b. Memory Map Table c. Job Table d. Memory Management Table
d. Job Table
In a paged memory allocation scheme, the ____ contains two values for each active job: the size of the job and the memory location where its Page Map Table is stored. a. Memory Map Table b. Page Access Table c. Memory Management Table d. Job Table
True
In a paged memory allocation scheme, to find the actual position of an instruction in memory, first the page number and displacement are determined. Then the operating system refers to the job's PMT to correlate the page with its page frame. True/False
a. virtual memory
One of the most important innovations of demand paging is that it makes ____ feasible. a. virtual memory b. spontaneous allocation c. automatic allocation d. parallel memory
False
Paged memory allocation offers the advantage that it doesn't require the entire job to be stored in memory during its execution. True/False
swapping
Page ___________ refers to the process of moving a page out of main memory and into secondary storage so another page can be moved into memory in its place.
replacement
The page ________________ policy is an algorithm used by virtual memory systems to decide or segment to remove from main memory when a page frame is needed and memory is full.
True
The primary advantage of storing programs in noncontiguous page frames (in a paged memory allocation scheme) is that main memory is used more efficiently because an empty page frame can be used by any page of any job. True/False
True
The segmented/demand paged memory allocation scheme is a combination of segmentation and demand paging, and it offers the logical benefits of segmentation, as well as the physical benefits of paging. True/False
c. locality of reference
The term "____" means that during any phase of its execution, a program references only a small fraction of its pages. a. structured programming b. working set c. locality of reference d. dynamic paging
True
Virtual memory can be implemented with both paging and segmentation. True/False
