Written below is a collection of my miscellaneous and scattered notes representing what I learned from this week:
[In regard to topic involving pages]
- The term "page" is used to represent a chunk of space from the virtual memory space
- The term "page frame" is used to represent a chunk of space from the physical memory space
- Generally, each "page" must correspond to a "page frame" (it is a 1 to 1 relationship) (only true if every page is mapped to a RAM)
- Scenario that falls outside of "generally" is when a page may not be mapped from a RAM (e.g. could come from a hard drive disk instead) or maybe a page is not mapped at all to begin with.
[In regard to topic involving virtual and physical memory space]
- A virtual memory space does not represent a block of contiguous memory from the physical memory space.
- Instead, virtual memory space is when multiple small chunks (called pages),
- mapped from either physical memory (called a RAM)
- or mapped from other areas (such as hard drive disk),
- or even an unmapped page (reserved pages),
are all virtually mapped together into a "fake" contiguous block of memory to give an illusion of a contiguous memory block.
- Metadata about a particular page is called a Page Table Entry (PTE),
- PTE itself is located within a small section of memory reserved just for them called a Page Table
[The overall structure/framework of virtual address space]
- a "virtual address space" is composed of "pages"
- and each of these "pages" are composed of "memory locations" that can hold certain data size (e.g. 1 byte [8 bits] for each "memory locations")
- and a "memory location" contains "memory data" (example of memory data: 0b10101100)
- and "memory address" points to a specific "memory location"
- and "memory address" is composed of "VPN" and "offset"
- and "memory address" IS NOT part of the "memory data" found within a "memory location"
So technically the term "virtual address space of 64 bytes" (found in our first lecture slide) means:
- "A virtual memory space that is composed of 64 memory locations, each containing 1 byte worth of memory data"
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