Change TCP congestion control for Ubuntu 8.04
For some reason, Ubuntu 8.04 LTS uses ‘reno’ for TCP congestion control instead of ‘cubic’ even though upstream kernels have had cubic as the default for a while.
Until a new kernel package comes out to fix this, you need to load the module at boot time via /etc/modules or modprobe tcp_cubic for now.
Next, edit /etc/sysctl.conf and set net.ipv4.tcp_congestion_control to cubic. Reload the parameters via “sysctl -p”