Options to set underlying socket configuration of SO_SNDBUF and SO_RCVBUF

[scottf]

! MAY OVERRIDE THE UNDERLYING JAVA SOCKET IMPLEMENTATION - USE AT YOUR OWN RISK

Socket Buffer Sizes

The default socket buffer sizes in Java depend on the underlying operating system, not Java itself. Java doesn't set explicit defaults - it uses the OS defaults.

Typical Default Values:

Linux:

• Receive Buffer (SO_RCVBUF): ~87,380 bytes (85 KB)
• Send Buffer (SO_SNDBUF): ~16,384 bytes (16 KB)

Windows:

• Receive Buffer: ~8,192 bytes (8 KB)
• Send Buffer: ~8,192 bytes (8 KB)

macOS:

• Receive Buffer: ~131,072 bytes (128 KB)
• Send Buffer: ~131,072 bytes (128 KB)

How to Check Current Values:

import java.net.*;

public class SocketBufferSize {
    public static void main(String[] args) throws Exception {
        Socket socket = new Socket();
        System.out.println("TCP Socket Defaults:");
        System.out.println("  Receive Buffer: " + 
            socket.getReceiveBufferSize() + " bytes");
        System.out.println("  Send Buffer: " + 
            socket.getSendBufferSize() + " bytes");
        socket.close();
    }
}

Miscellaneous Configuration:

Linux:

Check /proc/sys/net/core/rmem_default and /proc/sys/net/core/wmem_default
Can be modified via sysctl settings

[MauriceVanVeen]

LGTM

[jnmoyne]

LGTM