TCP_BBR

BBR implementation and research resources.

Enhanced BBR variants are modified by Yankee@hostloc and nanqinglang.

This repository keeps track of tcp_bbr.c from Elixir Bootlin.

Installation

DKMS installation (recommended)

1. Install dkms.
2. Download dkms_install.sh.
3. Run the script as root and follow the instructions.

This script will install BBR as a dkms module, which will be recompiled and reinstalled whenever the kernel gets updated. It will also let the system auto-load the BBR module at boot time and set the default congestion control method to BBR or the variant you choose during the installation.

Automated installation

1. Download install.sh.
2. Download the source code of your desired congestion control algorithm w.r.t. your kernel version.
3. Put the source code in the same directory as install.sh.
4. Run ./install.sh <algo> as root.

<algo> should be chosen from bbr, tsunami, nanqinlang or bbrplus (deprecated in v5.1+). The script assumes that the corresponding source code for <algo> is tcp_<algo>.c.

Manual installation (deprecated)

wget -O ./tcp_tsunami.c https://raw.githubusercontent.com/KozakaiAya/TCP_BBR/master/code/v5.5/tcp_tsunami.c
echo "obj-m:=tcp_tsunami.o" > Makefile
make -C /lib/modules/$(uname -r)/build M=`pwd` modules CC=/usr/bin/gcc
cp tcp_tsunami.ko /lib/modules/$(uname -r)/kernel/drivers/
echo 'tcp_tsunami' | sudo tee -a /etc/modules
depmod
modprobe tcp_tsunami
echo "net.core.default_qdisc=fq" >> /etc/sysctl.conf
echo "net.ipv4.tcp_congestion_control=tsunami" >> /etc/sysctl.conf
sysctl -p

Special note for Linux Kernel 4.15 & gcc 7.3

For some strange reasons, the compiler cannot find necessary header files. Therefore, echo "ccflags-y=-I/usr/lib/gcc/x86_64-linux-gnu/7/include" >> Makefile is needed.

Supported Ubuntu Versions

Ubuntu kernel version is obtained from Ubuntu Packages. Other supported version of BBR code can be found here.

Research Resources

Please refer to research/README.md.

Remark

Since Linux Kernel v5.1, bbrplus no longer needs to be updated, because most of its ideas have been merged to the mainline kernel.

Future Plan

• Port enhanced BBR from Kernel v5.0 to higher version without merging bbrplus.