Page (computer memory)

A memory page (English: page, called in German also tiled) is a computer science defined by the computer architecture and operating system number of directly consecutive memory locations in the logical memory space. The memory is divided into equal-sized memory pages.

By the use of pages of memory the operating system is possible to carry out a virtual memory management. The total memory is divided into tiles, and each address is interpreted in this computer architecture by the Memory Management Unit (MMU ) as logical address and converted into a physical address. In the MMU is in general a so-called descriptor cache ( Translation Lookaside Buffer ), in the hardware-based, the last page addresses and the associated tile addresses are latched and can thus be speeded up, access to the physical memory ( RAM ). If that is a current logical address, the page number in the descriptor cache before, the MMU needs to access the page table located in memory.

A part of the logical address is the page address while on the tile to be used in the main memory, while the other part addressed the relative address, the offset within the tile. This is the offset before the size of a tile.

Example

In IA32 architectures each 32 -bit address is interpreted as follows:

  • 20 bits indicate the selected memory page, ie a maximum of 220 memory pages.
  • 12 bits give the offset in the memory side, ie 212 bytes equal to 4 KiB ( each entry in the page is 1 byte long ), is the total size of a set by the operating system memory page and the same size of the tile.
  • Computer Architecture
  • Memory management
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