2.1.3+Explain+the+use+of+cache+memory


 * Students should be able to explain the effect of cache memory in speeding up the system as well as being able to explain how it is used.**

=**Cache**=

Cache is very fast and small memory that is placed in between the CPU and the main memory. Cache memory is used to reduce the average memory access times. This is done by storing the data that is frequently accessed in main memory addresses therefore allowing the CPU to access the data faster. This is due to the fact that cache memory can be read a lot faster than main memory. There are different types of cache (e.g. L1,L2 and L3)

The steps to access the data from cache memory are:

 * 1) A request is made by the CPU
 * 2) Cache is checked for data
 * 3) If the data is found in the cache it is returned to the CPU (this is called a cache hit)
 * 4) If the data is not found in the cache then the data will be returned from the main memory.

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 * [[image:CACHEMEM.gif width="355" height="366"]] || [[image:computer-memory-pyramid.gif]] ||