Virtual Memory Flashcards
What does the definition “Page” mean?
A fixed-size block of words of real memory. Typically 4 KB in size for 64-bit operating systems.
What does the definition “World” mean?
Any type that is size of a pointer. This corresponds to the width of the CPU’s registers. In Rust, usize and isize are word-length types.
What does the definition “Page fault” mean?
An error raised by the CPU when a valid memory address is requested that is not currently in physical RAM. This signals to the OS that at least one page must be swapped back into memory.
What does the definition “Swapping” mean?
Migrating a page of memory stored temporarily on disk from main memory upon request.
What does the definition “Virtual memory” mean?
The program’s view of its memory. All data accessible to a program is provided in its address space by the OS.
What does the definition “Real memory” mean?
The operating system’s view of the physical memory available on the system. In many technical texts, real memory is defined independently from physical memory, which becomes much more of an electrical engineering term.
What does the definition “Page table” mean?
The data structure maintained by the OS to manage translating from virtual to real memory.
What does the definition “Segment” mean?
A block within virtual memory. Virtual memory is divided into blocks to minimize the space required to translate between virtual and physical addresses.
What does the definition “Segmentation fault” mean?
An error raised by the CPU when an illegal memory address is requested.
What does the definition “MMU” mean?
A component of the CPU that manages memory address translation. Maintains a cache of recently translated addresses (called the TLB), which stands for the translation lookaside buffer, although that terminology has fallen from fashion
