Working of Cache Memory in Computer

Cache memory in computer is a small amount of random-access memory (RAM) that stores recently accessed information. When the computer needs to access this data, it can instead look in its cache, which is much faster than retrieving the information from the main RAM.

Cache memories are handy because they allow programs and systems to run more quickly by preventing them from having to constantly search for frequently used files on disk. Let’s talk about cache memory in computers and how much it affects your computer performance. Moreover, the cache can also help to protect the computer’s hard drive from becoming overloaded or damaged.

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Table of contents

• What is cache memory?
• How does the CPU cache work? 
• Types of cache memory
• How to check how much cache memory is there in your computer?
• How does cache memory affect the performance of the computer?
• Cache memory mapping
• Conclusion

What is Cache Memory?

Memory that stores data from the CPU is called cache memory. Your computer stores information that the CPU needs to access. For example, if you frequently search for a particular word, your computer keeps that word near the data you search for. For example, if you open Ms excel and then close it. And after some time, you again opened it. Now, it will take less time to get open as it was picked up from cache memory.

How Does the CPU Cache Work? 

The CPU needs to access ultra-fast memory to get the most out of its performance. The CPU cache works with this memory and the CPU first looks into the cache memory when it wants to access data. If the data is not there in cache memory, that is called a miss, and if it is found, it will be called a hit. Then it goes and searches the main memory.

If data is not found, it is accessed from the main memory, and a copy of that data is also copied into the cache memory. So that if next time the request for the same data comes, then that will be available in cache memory. If the data is not there in the main memory, then that secondary memory is searched. This will secondary memory search will take the most of the time. The memory controller gets the data from RAM and sends it to the CPU cache. The memory hierarchy also exists in the CPU cache.

Types of Cache Memory in Computer

1. Level 1 (L1) cache or first-level cache

L1 cache is the first cache level, which holds data that the CPU has recently used. It stores recently used data from the processor cores for quick access by other parts of the system. Data in this area is frequently accessed because it resides close to the CPU. L1 caches can typically hold 4 megabytes of data and are found on most processors today.

2. Level 2 (L2) cache 

The L2 cache holds data that the CPU has recently used and is likely to be used again. It is located mainly on graphics processing units or CPUs that use vector instructions, such as those used in games and 3D imaging applications.

3. The level 3(L3) cache

It is the third level of cache.

In the early days, the L3 memory cache was on the motherboard. It was long ago, and most CPUs were just single-core processors. Now the CPU’s L3 cache can be huge, and top-end consumer CPUs boast up to 32MB of L3 cache. Some server CPU L3 caches can exceed this by up to 64MB. The L3 cache is the largest but also the slowest cache storage unit.

4. Disk cache

You can also find the cache memory on your hard drive. This is called the “disk cache”. It is the slowest of all cache levels because the data is loaded from disk to memory. RAM can also store information about peripherals such as computer accessories and DVD drives in the peripheral’s cache.  

5. GPU Cache

Getting the data needed to render the graphic must be done very quickly, so it makes sense to use a caching system. When computer graphics are integrated, they are processed by a graphics processing unit (GPU) combined with a CPU in one chip. Both functions work on the same resource, limiting the GPU cache.

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How to Check How Much Cache Memory is There in Your Computer?

1. Press Ctrl + Shift + Esc keys to open Task Manager. 
2. In Task Manager, click the Performance tab.
3. Click on CPU in the left pane.
4. In the right pane, you will see L1, L2, and L3 Cache sizes listed at the bottom.

In this you can see that L1cache is 128 KB,L2 cache is 512 KB and L3 cache is 3 MB.

How Does Cache Memory Affect the Performance of the Computer?

Cache memory is a type of memory used to store data used frequently by the computer. This data is accessed frequently and stored in a location close to the processor. The cache memory helps improve the computer’s speed by containing the data and providing it to the processor when needed.

This decreases the need to search for the data on the storage device. The data stored in the cache memory is updated as frequently as possible. By improving the computer’s performance, the cache memory can help reduce the amount of time spent on tasks. This can help to improve the overall performance of the computer system. So when you want to buy a laptop or computer, you demand more RAM/main memory because more RAM will increase the speed of your running processes or applications. As more applications can be executed on the computer.As we know the applications are loaded in RAM when they are to execute.

Cache Memory Mapping

Since your computer stores information in different locations, it needs an address that tells the components where to find the data. Cache memory mapping is mapping a section of a computer’s system memory to an area of the physical memory. In other words, it stores frequently accessed data in a more accessible location on the computer’s hard drive. This can improve system performance by making the data more quickly accessible to the computer’s operating system and application programs.

Cache memory mapping is accomplished by the system BIOS or software running on the computer. After the BIOS or software has created the cache memory mapping, it signals the operating system and application programs to start using the mapped section of system memory instead of the resident memory.

Cache memory mapping can be used in various situations where frequently accessed data needs to be stored in a more accessible form. These include:

• When the computer is running multiple applications, each application needs access to different parts of the system memory.
• Cache memory mapping can be used to improve system performance by making data more quickly accessible to the computer’s operating system and application programs.

Conclusion

The main memory and cache memory are two essential types of memory in a computer. The main memory stores data temporarily. The other type of memory is cache memory. It’s the fastest type of memory. And over time, it needs to be refreshed. The cache memory gets refreshed when the data on the hard drive is read. Cache memory is usually accessed more often than main memory. Thus, it influences your computer performance. In this article, we talked about cache memory in computers and its types. If you like this article then please share it with your friends

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