How to Use BufReader and BufWriter for Performance in Rust

Wrap TcpStream in BufReader for reading and BufWriter for writing to reduce system calls and improve performance.

use std::io::{BufReader, BufWriter, Read, Write};
use std::net::TcpStream;

fn handle_connection(mut stream: TcpStream) {
    let mut buf_reader = BufReader::new(&stream);
    let mut buf_writer = BufWriter::new(&mut stream);

    let mut request = String::new();
    buf_reader.read_to_string(&mut request).unwrap();

    let response = "HTTP/1.1 200 OK\r\n\r\nHello";
    buf_writer.write_all(response.as_bytes()).unwrap();
    buf_writer.flush().unwrap();
}

Think of BufReader and BufWriter as a buffer or waiting room for data. Instead of making a trip to the operating system for every single byte you read or write, these tools collect data in a temporary holding area. This reduces the number of expensive trips to the OS, making your network or file operations significantly faster.