What is Cache?Cache hit and Cache miss

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What is Cache?

 --> It is a block of memory for temporary storage of data which will be used frequently.

--> Accessing data from cache will be faster when compared to accessing it from a main memory(RAM)

---> Caches are type of SRAM.SRAM are costlier than DRAM because it requires 6 transistors to store one bit whereas DRAM are cheaper as it requires only one transistor and capacitor, but the disadvantage with DRAM is that it has to be refreshed each time.

--->Need for cache's arised because the speed of the processor is more compared to the speed of the main memory.So in order to match the speed, cache is kept between processor and RAM

--->If a processor has to perform an I/O(read/write) operation on any memory location,it will check whether the data of that memory location is present in the memory or not.If it is present it will directly perform I/O operation on that memory.This is called cache hit.If the data is not present in the cache.It is called cache miss.In this situation,he will perform I/O operation from the memory and store in the cache and give it to the user.

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