Publish images for the linux/arm64 Docker platform

[ianks]

In #76 I mentioned a request to publish linux/arm64 Docker images. Currently, building on M1 is unbearably slow in many cases due to the virtualization overhead. I’ve almost given up on running RCD locally as a result.

Using linux/arm64 images removes the virtualization overhead and makes the local development experience much better.

[flavorjones]

@ianks I'm curious - is the aarch64-linux support not sufficient for your needs?

[ianks]

@ianks I'm curious - is the aarch64-linux support not sufficient for your needs?

I'm referring to the issue of compiling x86_64-linux on an arm64 machine. Currently, that requires full CPU emulation. Ideally, RCD could cut the x86_64-linux, etc images for multiple Docker platforms (linux/arm64 and linux/amd64)

[flavorjones]

Ah, right, I had totally forgotten the original context of this issue. Thanks for re-explaining.

[ianks]

@flavorjones I think this issue becomes simple to tackle now with Ubuntu base images

[flavorjones]

@ianks If you have the bandwidth, I'd gladly accept help. I'm unlikely to get to this in the next few weeks.

[ianks]

Been working on adding support to the cross-rs images, since they have all the bells and whistles already and already inherit from ubuntu:20.04. Once I get that merged, it should be a one line change here (and likely able to remove a bunch of code)

cross-rs/cross#1597

[larskanis]

I re-enable this issue since we don't have a automated build process for arm64 right now as discussed here.

[flavorjones]

@ianks How do you automate builds for the cross-rs arm64 platform images? Any advice here?

I poked around a bit and it looks like we might be able to apply for free credits to run ARM hardware as an open-source project: https://github.com/WorksOnArm/GitHub-Runners

Some related references:

• https://www.arm.com/markets/computing-infrastructure/works-on-arm
• https://newsroom.arm.com/blog/github-arm-integration
• https://github.com/actions/partner-runner-images?tab=readme-ov-file

Or we could just spin up a runner of our own on GCP or AWS, especially if we can get enough credits to cover it.

[flavorjones]

@larskanis said in #140:

To my understanding, per platform images can not be simply appended after pushing. Either the two host platforms must be pushed by one buildx command or two images must be pushed separately with different names and then a manifest with links to them must be pushed.

The rake task release:images uses the first method. So we can not release x86 from CI and arm from local that way.

If we can't figure out a way to push both platforms from CI, then I think we need to consider doing the manifest approach to decouple the two build processes. But I've never tried the manifest approach to stitch together images into a release, so I don't know what I don't know.