What is Cache Memory?

In this post you will learn about Cache memory and their types and advantages. Cache Memory is a special very high-speed memory. It is used to speedup and synchronizing with high-speed CPU. Cache memory is costlier than main memory or disk memory but economical than CPU registers. Cache memory is an extremely fast memory type that acts as a buffer between RAM and the CPU. It holds frequently requested data and instructions so that they are immediately available to the CPU when needed.

Cache memory is used to reduce the average time to access data from the Main memory. The cache is a smaller and faster memory which stores copies of the data from frequently used main memory locations. There are various different independent caches in a CPU, which stored instruction and data.

Cache memory lies between CPU and Main Memory.

It is also called CPU memory, that a computer microprocessor can access more quickly than it can access regular RAM. This memory is typically integrated directly with the CPU chip or placed on a separate chip that has a separate bus interconnect with the CPU.

Cache memory saves time and increases efficiency because the most recently processing data is stored in it which makes the fetching easier.

 Step 1 or Register –

It is a type of memory in which data is stored and accepted that are immediately stored in CPU. Most commonly used register is accumulator, Program counter, address register etc.

Step 2or Cache memory –

It is the fastest memory which has faster access time where data is temporarily stored for faster access.

Step 3 or Main Memory –

It is memory on which computer works currently it is small in size and once power is off data no longer stays in this memory

Step 4 or Secondary Memory –

It is external memory which is not fast as main memory but data stays permanently in this memory

Functions of Cache Memory:

The basic purpose of cache memory is to store program instructions that are frequently re-referenced by software during operation. Fast access to these instructions increases the overall speed of the software program.

The main function of cache memory is to speed up the working mechanism of computer.

Application of Cache Memory –

Usually, the cache memory can store a reasonable number of blocks at any given time, but this number is small compared to the total number of blocks in the main memory.

The correspondence between the main memory blocks and those in the cache is specified by a mapping function.

Types of Cache –

Primary Cache –

A primary cache is always located on the processor chip. This cache is small and its access time is comparable to that of processor registers.

Secondary Cache –

Secondary cache is placed between the primary cache and the rest of the memory. It is referred to as the level 2 (L2) cache. Often, the Level 2 cache is also housed on the processor chip.