Cache Memory in Computer

Kailash Chandra Behera | Thursday, December 24, 2020

Introduction

Cache memory in computer architecture is a small high-speed memory that contains frequently used data. Here in this article, we will discuss the definition of cached memory(cache meaning), types of cache memory, and levels of cache memory

Getting started

Cache Memory Definition:- Cache memory in a computer organization is a hardware or software component that stores data so that future requests for that data can be served faster, the data stored in a cache might be the result of an earlier computation or a copy of data stored elsewhere.

Types of Cache

There are two types of cache memory given below.

  1. Internal Cache
  2. External Cache

Internal Cache

A cache is a small high-speed memory that contains frequently used data. The use of cache avoids repeated reading of data from the slower main memory. The internal cache is located within the microprocessor.

External Cache

An external cache is any cache memory that is not built into a CPU chip. The external cache is designed to provide high-speed data storage and processing services to the computer processor, it’s primary/native cache, and the main memory. An external cache is also known as a secondary cache.

The external cache is used to supplement the internal cache, it is used when an internal cache is not present. It is placed between the CPU and the main memory.

Levels of Cache Memory

There are 3 main levels of cache memory which all have slightly different functions. All the cache memory is categorized as L1, L2, and L3. in the are given in detail different levels of cache meanings.

First Level Cache(L1).

This type of cache memory is faster, but smaller and would store the most frequently used portions of the program and cached data. This is introduced between the processor and the main memory.

Second Level Cache(L2).

The second level has higher capacity, as the processor speed increased there was a need to have second-level cache memory. it was implemented on the system motherboard SRAM chip.

Third Level Cache(L3).

The speed of the processor is further improved and 3 level cache introduced. The third level cache implemented on the system mainboard. It has the largest capacity and improves system performance to high-speed performance.

How does it Work?

Cache memory temporarily stores information(cached data) and programs that are commonly used by the CPU. When data is required, the CPU will automatically turn to cache memory in search of faster data access. This is because RAM is slower and is further away from the CPU.

When data is found in the cache memory, this is called a cache hit. Cache hits are served by reading data from the cache, which is faster than recomputing a result or reading from a slower data store; thus, the more requests that can be served from the cache, the faster the system performs.

When the cache does not have the processor’s required data, this is called a cache miss, and in this instance, the CPU will move onto the hard drive and use RAM.

Examples of Cache memory
  1. CPU Cache
  2. GPU Cache
  3. DSPs
  4. Disc Cache
  5. Web Cache
Advantage of cache
  1. The cache memory enhances the speed of the computer’s performance.
  2. The access time for cached data is minimal as it lies in the same chip.
  3. The instruction takes less time to execute because the same block of cached data is stored on the main memory which resides on the cache.
  4. The CPU and cache are connected to each other through a high capacity and speed local bus which makes data faster transfer.

Summary

Cache Memory is used to improvement the performance of a computer. I hope you have learned about cach and how the cach data in flow from one level to other.

Thanks