Build images for arm64

[amioranza]

Build images for arm64

[FelicianoTech]

Hi,

My team can't build ARM images for this purpose yet until the Docker executor itself supports ARM. Right now it does not. There is a feature request on CircleCI Ideas for this. I suggest upvoting it and sharing with other who would want the same feature so that our Product Management team can prioritise. https://ideas.circleci.com/cloud-feature-requests/p/support-arm-resource-class-on-docker-executor

[amioranza]

Hi @FelicianoTech, I didn't get your point. There is an issue open for while to add multiarch build support, I created this PR with the solution, and we can execute arm images on arm vm's. Currently I'm building the cimg images for ARM64 on my machine just because we are doing a PoC for AWS Graviton for our apps, but it is really easy to add the support for multiarch builds and start building your images for both architectures, intel and arm64, using circleci infra and using docker buildx, it does a cross compile builds.

[FelicianoTech]

and we can execute arm images on arm vm's

The Convenience Images, including this one, aren't decided to be used with the machine executor. These images are built specifically for the docker executor, which currently does not support ARM. The considering here isn't where the images are being built, but where they are designed to be run.

[fagiani]

@FelicianoTech I am not sure I follow this last comment as I see big players like Salesforce/Heroku using cimg images as base for their own images intended to run even off CircleCI elsewhere like AWS or other providers that currently offer ARM alternatives with better performance and price.

I'd like to understand better the relevance of Convenience Images specially regarding their exclusive relation with being built for docker executor as per what was stated.

BTW, @amioranza I've forked this repo and, after some struggle, was able to get mutiarch Dockerfiles with automated builds including an ARM64 version of it here.

I'd be willing to contribute with a PR if it ever gets considered.