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Under demand paging logical divisions of virtual memory, termed ___ are mapped t

ID: 3720844 • Letter: U

Question

Under demand paging logical divisions of virtual memory, termed ___ are mapped to, and loaded into ___ in physical RAM.

frames ... pages

blocks ... clusters

pages ... frames

blocks ... partitions

If an instruction or data item in virtual memory is referenced, what gets fetched into memory?

the specific instruction or data item

the entire page in which that instruction or data item is located

just enough data as comprises 1 word

a hard drive sector of data encompassing the instruction or data item referenced

How is a specific instruction or data item in a given page in virtual memory referenced?

by its file handle

by the page number and a page offset

by its block number

by its PCB

Reference to a page not already loaded in physical memory is referred to as a(n) ___ and results in a(n) ___

miss ... page fault

hit ... program crash

hit ... page offset

miss ... page swap

In a multitasking environment, an I/O request by a process that results in a page fault causes that process to go into a ___ state.

new

ready

running

blocked

terminated

An I/O request by a running process that results in a page fault causes the register values of that process to be ___.

pushed onto the stack or saved to the PCB

swapped out to the hard drive

destroyed

popped from the stack

If a page fault occurs but all frames are filled, the requested page will __

be pushed onto the stack or the process control block until a frame becomes available

be swapped out to the swap space of the hard drive

be terminated or masked so a higher priority process is not interrupted

overwrite an unwanted page in memory which has been copied to the swap space

frames ... pages

blocks ... clusters

pages ... frames

blocks ... partitions

If an instruction or data item in virtual memory is referenced, what gets fetched into memory?

the specific instruction or data item

the entire page in which that instruction or data item is located

just enough data as comprises 1 word

a hard drive sector of data encompassing the instruction or data item referenced

Explanation / Answer

1. Under demand paging logical divisions of virtual memory, termed pages are mapped to, and loaded into frames in physical RAM.

Reason - Pages refer to the virtual address space available in secondary memory while frames refer to the chunk of space available in physical memory, under demand paging a chunk of memory(pages) is copied from secondary memory into physical memory(frames) when the memory address required by the process is not present in the physical memory.

2. The specific instruction or data item in a given page in virtual memory is referenced by PCB(Process Control Block)

2a. Reference to a page not already loaded in physical memory is referred to as a miss and results in a   pageswap

2b. In a multitasking environment, an I/O request by a process that results in a page fault causes that process to go into a terminated state.

2c. An I/O request by a running process that results in a page fault causes the register values of that process to be popped from the stack.

2d. If a page fault occurs but all frames are filled, the requested page will overwrite an unwanted page in memory which has been copied to the swap space.