Recompile RetroPie with DistCC

[emclinux]

Here is my little guide on how to get distcc working to recompile Retropie. This guide is for Rpi3 and may or may not work on the 3+. For other Rpi versions it should be a quick trip into the crosstools-ng docs to get it working.

This guide is for ubuntu.
You can run this in vagrant or any other vm if you use a different OS. Or take these instructions as a jumping off point.

On distcc compile machines

First install needed software

apt-get install -y git build-essential python3 python3-dev autoconf distcc flex makeinfo help2man libtool libtool-bin ncurses-dev bison

Install crosstools-ng

git clone https://github.com/crosstool-ng/crosstool-ng
cd crosstool-ng
./bootstrap
./configure
make
sudo make install

Install cross toolchain

ct-ng armv8-rpi3-linux-gnueabihf
#This can take an hour or more.
ct-ng build

Fix permissions and set links

cd /home/<YOUR USER>/x-tools/armv8-rpi3-linux-gnueabihf
chmod +w bin
cd bin
for i in `ls -1 | sed -e 's/armv8-rpi3-linux-gnueabihf-//g'`; do ln -s armv8-rpi3-linux-gnueabihf-$i $i; done

Configure distcc
Open /etc/default/distcc and set the following

STARTDISTCC="true"
#Set this to your network range
ALLOWEDNETS="10.0.0.0/8"
LISTENER="0.0.0.0"
ZEROCONF="false"

Open /etc/init.d/distcc and set

PATH=/home/<YOUR USER>/x-tools/armv8-rpi3-linux-gnueabihf/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin

On RetroPie

Install distcc

sudo apt install distcc

Configure distcc
Open /etc/distcc/hosts and remove the +zeroconf line and add you hosts all on the same line
For example if your hosts are 10.0.0.2 10.0.0.3 and 10.0.0.4 then it would look like this

10.0.0.2 10.0.0.3 10.0.0.4

Open /etc/profile and reconfigure your path to have distcc first

PATH=/usr/lib/distcc:$PATH

Then make it active

. /etc/profile

After all that is done now you can run the retropie_packages or the retropie-setup scripts as normal just when it compiles the software it should use the hosts you set first and fail back to the rpi if it can't compile on the listed hosts.

There is much more to distcc and I will leave that to you to make it better. This is loosely based on http://www.raspberry-pi-geek.com/Archive/2016/17/Distributed-software-compilation-for-the-Raspberry-Pi

The trick was not the install of distcc but getting a working cross compiler working. The one listed in that guide will not work on retropie using an rpi3

If you want to monitor your distcc I find the best tool for me is running tail on the distcc log file on the compile hosts

tail -f /var/log/distccd.log

Some like distccmon-text so I will let you choose.

This should work for most things in retropie. Im still in testing for a lot of it so I don't know how X emulator works or why it won't use distcc. Compiling software can be tricky. Cross compiling software distributed over the network even more so.

*edit - change for loop link command to include all tools

[BuZz]

A lot of this functionality is built in

eg. on your ubuntu machine

sudo ./retropie_packages.sh crosscomp setup stretch

then on the rpi3 just install distcc, configure it to use Ubuntu machine.

for building:

PATH="/usr/lib/distcc:$PATH" MAKEFLAGS="-j4 PATH=/usr/lib/distcc:$PATH" ./retropie_packages.sh etc

note settings the PATH for makeflags is needed for some modules to use distcc.

retropie also includes the facility to build raspberry pi binaries on an x86 Ubuntu machine using an emulated chroot and the distcc on the host. see the "builder" module.