Speeding up the Travis Build to Decrease the Building Time

Meilix is the repository which uses build script to generate community version of lubuntu as LXQT Desktop. It usually takes around 25-26 to build and deploy the ISO as a Github Release on master branch.
Observing the build log we can see that there are most of the packages like debootstrap, squashfs-tool, etc which are being fetch and setup at the time of building which results in increasing build time.

The issue is to decrease the build time supplying the packages from Travis so that when we run build.sh we won’t be required to download them again and thus few minutes will get reduced.
We included list of packages to be pre-downloaded in .travis.yml

include:
  - os: linux
    addons:
      apt:
        sources:
          - ubuntu-toolchain-r-test
        packages:
          - debootstrap
          - genisoimage
          - p7zip-full
          - squashfs-tools
          - ubuntu-dev-tools
          - dpkg-dev
          - debhelper
          - fakeroot
          - devscripts

These are some important packages included in the build.sh  as devtools=”debootstrap genisoimage p7zip-full squashfs-tools ubuntu-dev-tools” which are always fetched, so we included it into .travis.yml and downloaded it before entering into the chroot environment. By specifying those packages in the .travis.yml, Travis provides those packages beforehand into the docker container so it will run our script. Since the scripts also include package then when the script runs apt-get it won’t download those packages again. They are specified outside the chroot environment because they are expected to be at the system the build.sh script is run to get the iso. By this way, we get a sharp decrease in build time as the internet in the Travis CI container is not so fast so the package download time can be avoided. Now the build is taking around 15-16 minutes to build and deploy.

One thing to note that we didn’t remove those packages off build.sh so that build.sh works outside Travis CI as well.

References:
Pull #176 by @abishekvashok
Speeding up Travis Build by Travis CI
Faster Build by atchai.com

Updating of Linux Standard Base (lsb) and Shorten of log of Meilix Build

Updating the Linux Standard Base of the Meilix

Originally Meilix uses the Ubuntu mirror to fetch the Kernel source for the building of the Operating System. Therefore whenever a user type lsb_release -a for fetching the required information, they get the Ubuntu build info. The task is to change the config file to update the Linux Base Information from Ubuntu to Meilix.

lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 17.04
Release: 17.04
Codename: zesty

We need to patch a file in the location meilix-default-settings/etc/lsb-release which contains the information of the lsb release and this will overwrite the original configuration of Meilix.
This is how the lsb-release file looks like now:

DISTRIB_ID=Meilix
DISTRIB_RELEASE=17.04
DISTRIB_CODENAME=meilix
DISTRIB_DESCRIPTION="Meilix 17.04"

We made the required changes in the file as shown above and the output is as follows:

Shorten the log length of Meilix in Travis

We are facing issues while deployment of Meilix ISO in Travis and the error follows is ReadTimeout Error. Example log of one of fail build is:

This error gets solved automatically and the the ISO gets deployment after 1 or 2 restart of the build. But this time the error doesn’t get solved and after several attempts of restart of build, the ISO doesn’t get deployed.

Reason behind the error:

Travis is taking a lot of time to build the ISO. Travis logs are exceeding the time limit.

Proposed solution:

Reduce the time of build or shift to a new CI.
Reduce the log of the build so as to get the log within 9999 lines.

Solution Implemented

The best solution is to reduce the number of lines used in the log and this will also reduce the time of the build.
I tried concealing some command outputs by appending >/dev/null 2>&1 to some of the commands that has long outputs and adding -y to the commands like:

apt-get -qq -y --purge install file-roller unrar

References

Wiki of Linux Standard Base
Linux Foundation lsb
Ubuntu answer to reduce log