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OS-Specific Configuration Hints: Mac OS X

As Mac OS X is mainly a BSD derivative, you can use similar mechanisms to tune the TCP stack - see under BSD OS Specific

TCP Socket Buffer Tuning

See the End System Tcp Buffer Sizing topic for general information about sizing TCP buffers.

For testing temporary improvements, you can directly use sysctl in a terminal window: (you have to be root to do that)

sysctl -w kern.ipc.maxsockbuf=8388608
sysctl -w net.inet.tcp.rfc1323=1
sysctl -w net.inet.tcp.sendspace=1048576
sysctl -w net.inet.tcp.recvspace=1048576
sysctl -w kern.maxfiles=65536
sysctl -w net.inet.udp.recvspace=147456
sysctl -w net.inet.udp.maxdgram=57344
sysctl -w
sysctl -w

For permanent changes that last over a reboot, insert the appropriate configurations into Ltt>/etc/sysctl.conf. If this file does not exist must create it. So, for the above, just add the following lines to sysctl.conf:


Note This only works for OSX 10.3 or later! For earlier versions you need to use /etc/rc where you can enter whole sysctl commands.

Users that are unfamiliar with terminal windows can also use the GUI tool "TinkerTool System" and use its Network Tuning option to set the TCP buffers.

TinkerTool System is available from:

-- ChrisWelti - 30 Jun 2005

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