Ramfs is a very simple FileSystem that exports Linux's disk cacheing mechanisms (the page cache and dentry cache) as a dynamically resizable ram-based filesystem.

ramfs 是一个基于linux缓存机制（page cache and dentry cache）的简易文件系统，基于ram，大小可动态调整。

Normally all files are cached in memory by Linux. Pages of data read from backing store (usually the ?block_device the filesystem is mounted on) are kept around in case it's needed again, but marked as clean (freeable) in case the Virtual Memory system needs the memory for something else. Similarly, data written to files is marked clean as soon as it has been writt...