What is cache memory in Linux free?

Free Buffer and Cache in Linux

Linux is designed in such a way that it looks into the disk cache before looking onto the disk. If it finds the resource in the cache, then the request doesn’t reach the disk. If we clean the cache, the disk cache will be less useful as the OS will look for the resource on the disk.

Is cached memory free memory Linux?

Cached memory is memory that Linux uses for disk caching. However, this doesn’t count as “used” memory, since it will be freed when applications require it. Hence you don’t have to worry if a large amount is being used.