What Is Buffer and Cache Memory in Linux?

Short answer: Cached is the size of the page cache. Buffers is the size of in-memory block I/O buffers. … Buffers are in-memory block I/O buffers. They are relatively short-lived. Prior to Linux kernel version 2.4, Linux had separate page and buffer caches.

What is buffer and cache?

Buffer is a part of the primary memory. They are structures present and accessed from the primary memory (RAM). On the other hand, cache is a separate physical memory in a computer’s memory hierarchy. Buffer is also sometimes called as – Buffer cache.

Why is buffer cache memory needed in Linux?

Linux always tries to use RAM to speed up disk operations by using available memory for buffers (file system metadata) and cache (pages with actual contents of files or block devices). This helps the system to run faster because disk information is already in memory which saves I/O operations.