#!/bin/sh
#
# Kernel tuning for MacOS X.3
# Paul Day, paul ( at ) bur.st
#

# Either run this as root each time you reboot, or
# add it into /etc/sysctl.conf as "variable = value"

# IPC max number of incoming connections in queue
sysctl -w kern.ipc.somaxconn=1024
# IPC max buffering
sysctl -w kern.ipc.maxsockbuf=523288
# IPC max number of sockets
sysctl -w kern.ipc.maxsockets=2048
# And nmb clusters
sysctl -w kern.ipc.nmbclusters=16384
# Set max number of processes
sysctl -w kern.maxproc=2048
# Set max number of vnodes
sysctl -w kern.maxvnodes=20784
# Set max number of files
sysctl -w kern.maxfiles=15000
# Time out dead NFS connections a little quicker.
# Put this up for 10.3 as it handles them well itself.
sysctl -w vfs.generic.nfs.client.initialdowndelay=15
sysctl -w vfs.generic.nfs.client.nextdowndelay=15
# Tune IP port ranges
sysctl -w net.inet.ip.portrange.first=40000
sysctl -w net.inet.ip.portrange.hifirst=45000
sysctl -w net.inet.ip.portrange.hilast=65532
sysctl -w net.inet.ip.portrange.last=65535
sysctl -w net.inet.ip.portrange.lowfirst=1022
sysctl -w net.inet.ip.portrange.lowlast=400
# Other network buffering
sysctl -w net.local.stream.recvspace=16000
sysctl -w net.local.stream.sendspace=16000
sysctl -w net.local.dgram.recvspace=8000
# keep the following at 24k for decent ssh, even while still downloading
# Up to 65535 for faster downloads when you have decent latency-free bandwidth
# (ie, _not_ DSL which dies badly as it saturates)
sysctl -w net.inet.tcp.sendspace=24000
sysctl -w net.inet.tcp.recvspace=24000
sysctl -w net.inet.udp.recvspace=41600
sysctl -w net.inet.raw.recvspace=8192
sysctl -w net.local.dgram.maxdgram=4196
# Turn off RFC1323 TCP large windows.
sysctl -w net.inet.tcp.rfc1323=0
# Enable Path MTU discovery
sysctl -w net.inet.tcp.path_mtu_discovery=1
# ICMP limit
sysctl -w net.inet.icmp.icmplim=1024
# Stop redirects
sysctl -w net.inet.icmp.drop_redirect=1
sysctl -w net.inet.icmp.log_redirect=1
sysctl -w net.inet.ip.redirect=0
# Stop source routing
sysctl -w net.inet.ip.sourceroute=0
sysctl -w net.inet.ip.accept_sourceroute=0
# Stop broadcast ECHO response
sysctl -w net.inet.icmp.bmcastecho=0
# Stop other broadcast probes
sysctl -w net.inet.icmp.maskrepl=0
# TCP delayed ack off
sysctl -w net.inet.tcp.delayed_ack=0
# Turn off forwarding
sysctl -w net.inet.ip.forwarding=0
# Turn on strong TCP sequencing
sysctl -w net.inet.tcp.strict_rfc1948=1
# Make ipfw debugging verbose
sysctl -w net.inet.ip.fw.verbose=1
sysctl -w net.inet.ip.fw.verbose_limit=65535
# Make Safari time-out smaller
defaults write com.apple.Safari WebKitInitialTimedLayoutDelay 0.25