WGU 191 Chapter 7 and 8 on Virtual and
Main Memory Exam Review Questions
and A Level Marking Scheme Latest
2024/2025
Interrupt driven - correct answer When the CPU does not poll the control bit, but rather
gets an interrupt signal
Buddy-system/power-of-2-allocator - correct answer Allocates memory from a fixed-
size segment consisting of physically contiguous pages via units sized as a power of
2(or rounded up to the next as needed).
Buddy - correct answer When a larger memory block is divided into a smaller part to
satisfy the request. Two smaller parts of a block are of equal size and called buddies.
Note that this may cause fragmentation (i.e. if a 11kb block is needed but 16kb block is
allocated(b/c it's a power of 2))
Coalescing - correct answer If needed split blocks of memory (buddies) can come
together to form larger segments of memory if needed
Slab allocation of kernel memory - correct answer A slab is one or more physically
contiguous pages
Cache allocation of kernel memory - correct answer Consists of one or more slabs.
There is a single cache for each unique kernel data structure
Objects - correct answer Objects populate the cache(multiple slabs) of the kernel data
structure that the cache represents (e.g. semaphore cache has semaphore objects)
Prepaging - correct answer Bringing into memory at one time all pages that will be
needed
, Resolution - correct answer Isolating the memory that is actually needed through a
smaller page size
TLB Reach - correct answer The amount of memory accessible from the translation
lookaside buffer. Found by the number of entries multiplied by the page size
page locking/pinning - correct answer ensures a process stays in main memory and is
exempt from paging.
Clustering - correct answer Handling a page fault by bringing in not only the faulting
page, but also several pages following the faulting page.
Working set minimum - correct answer The minimum number of pages the process is
guaranteed to have in memory up to its working set maximum
Automatic working set trimming - correct answer When free memory falls below a
threshold, the virtual memory will use this to restore the memory above the threshold
Pageout - correct answer when pages are written to disk
Priority paging - correct answer Distinguishing pages that have been allocated to
processes versus pages that have been allocated to regular files
True or False? A program does not need to be stored in memory in its entirety. - correct
answer True
True or False? A physical address space is at least as large as a virtual address space.
- correct answer False
Main Memory Exam Review Questions
and A Level Marking Scheme Latest
2024/2025
Interrupt driven - correct answer When the CPU does not poll the control bit, but rather
gets an interrupt signal
Buddy-system/power-of-2-allocator - correct answer Allocates memory from a fixed-
size segment consisting of physically contiguous pages via units sized as a power of
2(or rounded up to the next as needed).
Buddy - correct answer When a larger memory block is divided into a smaller part to
satisfy the request. Two smaller parts of a block are of equal size and called buddies.
Note that this may cause fragmentation (i.e. if a 11kb block is needed but 16kb block is
allocated(b/c it's a power of 2))
Coalescing - correct answer If needed split blocks of memory (buddies) can come
together to form larger segments of memory if needed
Slab allocation of kernel memory - correct answer A slab is one or more physically
contiguous pages
Cache allocation of kernel memory - correct answer Consists of one or more slabs.
There is a single cache for each unique kernel data structure
Objects - correct answer Objects populate the cache(multiple slabs) of the kernel data
structure that the cache represents (e.g. semaphore cache has semaphore objects)
Prepaging - correct answer Bringing into memory at one time all pages that will be
needed
, Resolution - correct answer Isolating the memory that is actually needed through a
smaller page size
TLB Reach - correct answer The amount of memory accessible from the translation
lookaside buffer. Found by the number of entries multiplied by the page size
page locking/pinning - correct answer ensures a process stays in main memory and is
exempt from paging.
Clustering - correct answer Handling a page fault by bringing in not only the faulting
page, but also several pages following the faulting page.
Working set minimum - correct answer The minimum number of pages the process is
guaranteed to have in memory up to its working set maximum
Automatic working set trimming - correct answer When free memory falls below a
threshold, the virtual memory will use this to restore the memory above the threshold
Pageout - correct answer when pages are written to disk
Priority paging - correct answer Distinguishing pages that have been allocated to
processes versus pages that have been allocated to regular files
True or False? A program does not need to be stored in memory in its entirety. - correct
answer True
True or False? A physical address space is at least as large as a virtual address space.
- correct answer False
