Buffering is the action I/O devices take in order to efficiently transfer data to or from the operating
system. Instead of directly transferring data bit-by-bit (literally) via system calls and registers, which is slow and requires context switch after context switch, we fill a buffer (or two, or three) with data, which is periodically transferred to or from main program control. We can also perform double or triple buffering where two-way efficiency is gained. It can be advantageous when we need to transfer large volumes of data, and at the same time may be disadvantageous due to overheads – if the network is high-speed the
time to copy between buffers might be comparable to the time spent actually transferring the data!
Titany answered the question on April 26, 2022 at 13:20
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