Github action to maximize the available disk space on Github runners
By default, public shared Github runners come with around 25-29 GB of free disk space to be consumed by your build job.
If this is too little for you, and your build job runs out of disk space, this action might be for you.
If not: please go on, there’s nothing to see here.
This action maximizes the available disk space on public shared GitHub runners, by
Depending on the use case, you can gain more than double the original space.
The idea came up when I tried to build a Fedora Linux Kernel RPM on Github, and the Job aborted due to disk space issues.
root-reserve-mb
, similarly for /mnt
and temp-reserve-mb
. While your build job will usually run (and consume disk space) in $GITHUB_WORKSPACE
mostly, other parts might require additional space in other places — e.g. /var/lib/docker
for docker images, when running docker build steps, but also apt install
will install to the root volume. Increase root-reserve-mb
or temp-reserve-mb
accordingly in these cases — or set overprovision-lvm
to true.rm -rf
on specific folders, not by using a package manager or anything sophisticated. While this is quick and easy, it might delete dependencies that are required by your job and so break your build (e.g. because your build job uses a .NET based tool and you removed the required runtime).Btw: the choice of removable packages is not an expression of dislike against these — they were just the largest folders for a single toolkit I could find quickly.
At the time of writing, public Github-hosted runners are using Azure DS2_v2 virtual machines, featuring a 84GB OS disk on /
and a 14GB temp disk mounted on /mnt
.
This action does the following:
/
and /mnt
(the temp disk) to an LVM volume group${GITHUB_WORKSPACE}
by default)This results in the space of the previously installed packages and the temp disk being available for your build job.
You should most probably use this action as the first build step, even before actions/checkout
. Since this action mounts a volume over the current working directory by default, the current content of the working directory will be inaccessible afterwards.
With the default configuration, you’re gaining about 7-8 GB of disk space. You can trade in swap space or disk reserve to get more and remove software that is unnecessary for your build job (see this table for examples and the expectable amount of space.
When removing software, consider that the removal of large amounts of files (which this is) can take minutes to complete. On the upside, you’ll get more than 60 GB of disk space available if you actually need it.
name: My build action requiring more space
on: push
jobs:
build:
name: Build my artifact
runs-on: ubuntu-latest
steps:
- name: Maximize build space
uses: easimon/maximize-build-space@master
with:
root-reserve-mb: 512
swap-size-mb: 1024
remove-dotnet: 'true'
- name: Checkout
uses: actions/checkout@v3
- name: Build
run: |
echo "Free space:"
df -h
All inputs are optional and default to the following, gaining about 7-8 GB additional space.
root-reserve-mb:
description: 'Space to be left free on the root filesystem, in Megabytes.'
required: false
default: '1024'
temp-reserve-mb:
description: 'Space to be left free on the temp filesystem (/mnt), in Megabytes.'
required: false
default: '100'
swap-size-mb:
description: 'Swap space to create, in Megabytes.'
required: false
default: '4096'
overprovision-lvm:
description: |
Create the LVM disk images as sparse files, making the space required for the LVM image files *appear* unused on the
hosting volumes until actually allocated. Use with care, this can lead to surprising out-of-disk-space situations.
You should prefer adjusting root-reserve-mb/temp-reserve-mb over using this option.
required: false
default: 'false'
build-mount-path:
description: 'Absolute path to the mount point where the build space will be available, defaults to $GITHUB_WORKSPACE if unset.'
required: false
pv-loop-path:
description: 'Absolute file path for the LVM image created on the root filesystem, the default is usually fine.'
required: false
default: '/pv.img'
tmp-pv-loop-path:
description: 'Absolute file path for the LVM image created on the temp filesystem, the default is usually fine. Must reside on /mnt'
required: false
default: '/mnt/tmp-pv.img'
remove-dotnet:
description: 'Removes .NET runtime and libraries.'
required: false
default: 'false'
remove-android:
description: 'Removes Android SDKs and Tools.'
required: false
default: 'false'
remove-haskell:
description: 'Removes GHC (Haskell) artifacts.'
required: false
default: 'false'
remove-codeql:
description: 'Removes CodeQL Action Bundles.'
required: false
default: 'false'
remove-docker-images:
description: 'Removes cached Docker images.'
required: false
default: 'false'