Caching and Buffering

Caching and buffering techniques apply to both read and write operations. Computer systems always strive for optimization and they want to do so in any way possible.

Let's consider read operations first. They are simpler than write operations as they do not change any existing data in memory. The OS caches important blocks in the system memory, which allows for faster read operations.

In the case of write operations, the write buffering technique is used. Some of the write operations are delayed and are grouped to be sent in batches at once. This allows the system to schedule I/Os (just like processes!) and increases performance.