Cache is small high speed memory usually Static RAM (SRAM) that contains the most recently accessed pieces of main memory.
In todayÃƒÂ¢Ã¢â€šà ¬Ã¢â€žÂ¢s systems , the time it takes to bring an instruction (or piece of data) into the processor is very long when compared to the time to execute the instruction. Therefore a bottle neck forms at the input to the processor. Cache memory helps by decreasing the time it takes to move information to and from the processor. Therefore cache memory allows small portions of main memory to be accessed 3 to 4 times faster than DRAM (main memory).
The theory that explains this performance is called †œLocality of Reference.ââ ¬Â The concept is that at any given time the processor will be accessing memory in a small or localized region of memory. The
cache loads this region allowing the processor to access the memory region faster.
(Yes - i got this somewhere else
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