Translation lookaside buffer - Definition

Translation Lookaside Buffer is a buffer (or cache) in a CPU that contains parts of the Page table which references between virtual and real addresses. This buffer has a certain number of entries and is used for speed improvement. The buffer is typically a CAM (content addressable memory) in which the search key is the virtual address and the search result is a real or physical address (which, perversely, may not be the same thing). If the CAM search yields a match the translation is foregone and the match data are used. Otherwise, if no match exists the translation proceeds which will take several more cycles to complete - particularly if the translation tables are swapped out into secondary storage.

Example Usage of Translation