Cached memory in Linux is a portion of your system's RAM that the operating system uses to store frequently accessed data from the hard drive. It acts like a temporary storage area, speeding up access to files and improving overall system performance. When you request a file, Linux checks the cache first. If the file is found in the cache, it's retrieved much faster than reading it from the hard drive. This process is known as disk caching.
Here's how it works:
- Linux keeps track of recently accessed files and their data in the cache.
- When you need a file, Linux checks the cache first.
- If the file is found in the cache, it's quickly retrieved, saving time and resources.
- If the file isn't in the cache, Linux retrieves it from the hard drive and adds it to the cache for future use.
Benefits of cached memory:
- Improved performance: Faster access to frequently used data significantly boosts system performance.
- Reduced disk usage: Storing data in RAM instead of constantly reading from the hard drive minimizes disk I/O operations, saving wear and tear on your hard drive.
Important to Note:
- Cached memory is not the same as used memory. Even though the free command might show a significant amount of "cached" memory, that memory is still available for other processes when needed.
- The cache size can fluctuate depending on your system usage.
