Acronym of TLB

( Translation Lookaside Buffer ) T El, (symbol, abbreviation TLB) a memory mediator in the CPU is that the parts of the table on the page in order to translate a virtual address to physical, but in their maintenance. The virtual memory amount of the fixed entries, and to improve the speed of translation of a virtual address are used. This virtual memory is typically a (CAM) the content of the memory address is, the search key of the address is virtual and search results address real or physical is usually not the same thing). If you search for CAM to result result. translation known and the data match is used. If no data is found, the translation within the table on the page continue find that several cycles of the more lasts up to complete – particularly if the translation tables to memory secondary submitted.

TLB in to address memory physical notes. TLB may be between the CPU and memory, I CACHE, or between memory I and memory the initial place. This depends on that the memory of his absence from the address of this virtual uses or addressing physical. A solution for optimized, cached physical address, this is to search the TLB with access to a cachet to the parallel do. Bits, the value of any virtual address (for example, in a system virtual memory with pages 4 ., the 12-bit lower address of the virtual ) in the conversion of virtual to physical change not find. In each access to the cached two operations can be done : an index within the data cached is stored, then a compare tags for line of cached that have been found. If cached, so structured was that it was only using the bits that translations don't change. index, this. cached can Operation indicator this your in when the TLB bit, rewarding the address translation does not do. Then the address is translated, the TLB to cached sent. Cached a comparison of label is done to determine the access to the target hit or an error occurred.

When a error the lack of entries in the TLB Miss to be happening, in architecture, modern two procedures done. With the management of the hardware TLB, the CPU in the tables, the search page does to see to address virtual memory specified entry exists or not. If an entry in. entries to the TLB be brought and access to TLB re-done. If an entry in the table on the page, there is not a error, defect pixel occurs, and the operating system, you must the data needed to memory bring. With TLB software management. a error, TLB, an exception "error TLB" produces and the operating system must be tables page over, and translate the software to do. Then, operating system, translation in TLB load and makes the app from the command that caused the error, TLB is resumed.

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