Linux VM TCP UDP Tunning

Network optimization among server VMs is a hot topic as read in recent discussion. Back to the old-school optimization strategies, I find them useful in the VM world.

The followings are Linux network settings for high throughput interface card:

#
#
# Add these lines to /etc/sysctl.conf as appropriate
#

vm.swappiness = 10

net.core.wmem_max = 8388608

net.core.rmem_max = 8388608

net.core.rmem_default = 65535

net.core.wmem_default = 65535

net.ipv4.tcp_rmem = 4096 87380 8388608

net.ipv4.tcp_wmem = 4096 65536 8388608

net.ipv4.tcp_mem = 8388608 8388608 8388608

net.ipv4.route.flush = 1

net.ipv4.tcp_window_scaling = 1

net.ipv4.tcp_timestamps = 1

net.ipv4.tcp_sack = 1

Thanks for the tips:
http://wwwx.cs.unc.edu/~sparkst/howto/network_tuning.php
http://fasterdata.es.net/fasterdata/host-tuning/linux/