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This article mainly explains the difference between cached and buffers in linux. The content of the explanation is simple and clear, and it is easy to learn and understand. Please follow the editor's train of thought to study and learn the difference between cached and buffers in linux.

Use the free command under linux to check memory usage. There are buffers and cached. Here is the difference between them:

Cached is between cpu and memory, and buffer is between memory and disk, all to solve the problem of unequal speed.

Buffer is about to be written to disk, and cache is read from disk.

Buffer: memory as buffer cache, read and write buffer for block devices

Cache: memory as page cache, cache of file system

If the value of cache is large, it means that cache lives in a large number of files. If frequently accessed files can be held by cache, then the read IO of the disk must be very small.

Buffers is a buffer designed for block devices. For example, disk read and write, centralize the decentralized write operations, reduce the disk I / O, so as to improve system performance. For example, cp a file into a U disk, but the read and write indicator of the U disk does not flash, and it takes a while to flash. The buffer is emptied when uninstalling, so sometimes it takes a few seconds to uninstall a device.

Cached is the content that has been read by the cache. The next time it is read, if it is hit in the cache, it will be read directly from the cache, otherwise the disk will be read. Due to the limited cache space, useless caches will be moved to swap after a period of time, so sometimes when you see that there is still a lot of physical memory, swap is utilized.

Thank you for reading, the above is the content of "the difference between cached and buffers in linux". After the study of this article, I believe you have a deeper understanding of the difference between cached and buffers in linux, and the specific use needs to be verified in practice. Here is, the editor will push for you more related knowledge points of the article, welcome to follow!

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